[{"question":"Who proposed the theory of evolution by natural selection?","choices":["darwin","Scopes","Linnaeus","shaw"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each specific polypeptide has a unique linear sequence of which acids?","choices":["hydrochloric","lactic","amino","fatty"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"A frameshift mutation is a deletion or insertion of one or more of what that changes the reading frame of the base sequence?","choices":["proteins","nucleotides","genes","carotenoids"],"answer":"B","rationale":"A frameshift mutation is a deletion or insertion of one or more nucleotides that changes the reading frame of the base sequence. Deletions remove nucleotides, and insertions add nucleotides. Consider the following sequence of bases in RNA:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is an area of land called that is wet for all or part of the year?","choices":["wetland","grassland","plains","tundra"],"answer":"A","rationale":"A wetland is an area that is wet for all or part of the year. Wetlands are home to certain types of plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Surface waters are heated by the radiation from?","choices":["the moon","gamma rays","decomposition","the sun"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are arteries, veins, and capillaries examples of?","choices":["muscles","organs","blood vessels","tissue"],"answer":"C","rationale":"Blood vessels include arteries, veins, and capillaries.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Biochemical reactions of metabolism include what two general categories?","choices":["catabolic and anabolic","innumerable and anabolic","discrete and telltale","telltale and anabolic"],"answer":"A","rationale":"Biochemical reactions of metabolism can be divided into two general categories: catabolic reactions and anabolic reactions. You can watch an animation showing how the two categories of reactions are related at this URL: http:\/\/classes. midlandstech. edu\/carterp\/courses\/bio225\/chap05\/lecture1. htm.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Compounds with aluminum and silicon are commonly found in the clay fractions of soils derived from what?","choices":["mineral ash","volcanic ash","volatile ash","ground ash"],"answer":"B","rationale":"Compounds with aluminum and silicon are commonly found in the clay fractions of soils derived from volcanic ash. One of these compounds is vermiculite, which is formed in reactions caused by exposure to weather. Vermiculite has the following formula: Ca0.7[Si6.6Al1.4]Al4O20(OH)4. (The content of calcium, silicon, and aluminum are not shown as integers because the relative amounts of these elements vary from sample to sample. ) What is the mass percent of each element in this sample of vermiculite?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What organ has four major regions: the cerebrum, the diencephalon, the stem, and the cerebellum?","choices":["heart","liver","lungs","brain"],"answer":"D","rationale":"13.2 | The Central Nervous System By the end of this section, you will be able to: \u2022 Name the major regions of the adult brain \u2022 Describe the connections between the cerebrum and brain stem through the diencephalon, and from those regions into the spinal cord \u2022 Recognize the complex connections within the subcortical structures of the basal nuclei \u2022 Explain the arrangement of gray and white matter in the spinal cord The brain and the spinal cord are the central nervous system, and they represent the main organs of the nervous system. The spinal cord is a single structure, whereas the adult brain is described in terms of four major regions: the cerebrum, the diencephalon, the brain stem, and the cerebellum. A person\u2019s conscious experiences are based on neural activity in the brain. The regulation of homeostasis is governed by a specialized region in the brain. The coordination of reflexes depends on the integration of sensory and motor pathways in the spinal cord.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What can refer to a rope in a particular shape and a genetic structure involved in splicing?","choices":["noose","tourniquet","braid","lariat"],"answer":"D","rationale":"A lariat can refer to a rope in the form of a lasso. But it is also a genetic structure involved in splicing.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the ratio of the mass of an object to its volume?","choices":["diameter","frequency","median","density"],"answer":"D","rationale":"Density is the ratio of the mass of an object to its volume.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most common type of anemia?","choices":["vitamin d - def","calcium - def","vitamin k - def","iron-def"],"answer":"D","rationale":"Anemia may not have any symptoms. Some people with anemia feel weak or tired in general or during exercise. They also may have poor concentration. People with more severe anemia often get short of breath during times of activity. Iron-deficiency anemia is the most common type of anemia. It occurs when the body does not receive enough iron. Since there is not enough iron, hemoglobin, which needs iron to bind oxygen, cannot function properly.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What stimulates milk production in mammals?","choices":["prolactin","estrogen","testosterone","neurotoxin"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"During telophase , the chromosomes begin to uncoil and form what?","choices":["nucleus","mucosa","chromatin","mitochondria"],"answer":"C","rationale":"During telophase , the chromosomes begin to uncoil and form chromatin. This prepares the genetic material for directing the metabolic activities of the new cells. The spindle also breaks down, and new nuclear membranes form.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The science dealing with the study of the atmosphere is known as what?","choices":["meteorology","geology","cosmology","climatology"],"answer":"A","rationale":"Meteorologists don\u2019t study meteors\u2014they study the atmosphere! The atmosphere is a thin layer of gas that surrounds Earth. The word \u201cmeteor\u201d refers to things in the air. Meteorology includes the study of weather patterns, clouds, hurricanes, and tornadoes. Meteorology is very important. Using radars and satellites, meteorologists work to predict, or forecast, the weather ( Figure below ). Meteorologists are getting better at predicting the weather all the time. Meteorologists wonder how to better predict weather. They wonder what the effects of rising water vapor in the atmosphere will be on weather.","split":"validation","source_dataset":"sciq","subject":null},{"question":"On what basis are the eras of the phanerozoic eon separated?","choices":["sparse extinctions","mass birthings","low birth rates","mass extinctions"],"answer":"D","rationale":"The eras of the Phanerozoic Eon are separated by mass extinctions . During these events, large numbers of organisms became extinct very rapidly. There have been several extinctions in the Phanerozoic. Two mass extinctions stand out more than the others. One took place at the end of the Paleozoic. The other took place at the end of the Mesozoic.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of response is generated when a stimulus is received by the nervous system?","choices":["a action potential","a motor response","a sensory response","a neural response"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Fluid in the pseudocoelom serves as a hydrostatic what?","choices":["vacuum","shower","skeleton","cell membrane"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"How will global warming eliminate some islands and reduce the area of others?","choices":["raise sea levels","unafect sea levels","lower sea levels","affect sea levels"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the secretion of saliva?","choices":["perspiration","excretion","salivation","craving"],"answer":"C","rationale":"Regulation of Salivation The autonomic nervous system regulates salivation (the secretion of saliva). In the absence of food, parasympathetic stimulation keeps saliva flowing at just the right level for comfort as you speak, swallow, sleep, and generally go about life. Over-salivation can occur, for example, if you are stimulated by the smell of food, but that food is not available for you to eat. Drooling is an extreme instance of the overproduction of saliva. During times of stress, such as before speaking in public, sympathetic stimulation takes over, reducing salivation and producing the symptom of dry mouth often associated with anxiety. When you are dehydrated, salivation is reduced, causing the mouth to feel dry and prompting you to take action to quench your thirst. Salivation can be stimulated by the sight, smell, and taste of food. It can even be stimulated by thinking about food. You might notice whether reading about food and salivation right now has had any effect on your production of saliva. How does the salivation process work while you are eating? Food contains chemicals that stimulate taste receptors on the tongue, which send impulses to the superior and inferior salivatory nuclei in the brain stem. These two nuclei then send back parasympathetic impulses through fibers in the glossopharyngeal and facial nerves, which stimulate salivation. Even after you swallow food, salivation is increased to cleanse the mouth and to water down and neutralize any irritating chemical remnants, such as that hot sauce in your burrito. Most saliva is swallowed along with food and is reabsorbed, so that fluid is not lost.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most common sti in the u.s.?","choices":["herpes","syphilis","chlamydia","genital warts"],"answer":"C","rationale":"Chlamydia is the most common STI in the U. S. As shown in the graph in Figure below , females are much more likely than males to develop chlamydia. Like most STIs, rates of chlamydia are highest in teens and young adults.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What plant structures are the main avenues by which water evaporates from the sporophyte?","choices":["chloroplasts","stomata","chlorophyll","veins"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Decomposers break down dead organisms into nutrients and what?","choices":["gases","soil","fluids","tissues"],"answer":"A","rationale":"Decomposers break down dead organisms into nutrients and gases so that they can be used by other organisms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the use of technology to treat genetic disorders or change organisms so they are more useful to people?","choices":["biotechnology","nanotechnology","biology","physiology"],"answer":"A","rationale":"Biotechnology is the use of technology to treat genetic disorders or change organisms so they are more useful to people. Methods include gene cloning. Applications include gene therapy and genetically modified food crops.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What science specialty, with a set of like-named scientific laws, refers to the study of energy and energy transfer involving physical matter?","choices":["geology","thermodynamics","chemistry","meteorology"],"answer":"B","rationale":"6.3 | The Laws of Thermodynamics By the end of this section, you will be able to: \u2022 Discuss the concept of entropy \u2022 Explain the first and second laws of thermodynamics Thermodynamics refers to the study of energy and energy transfer involving physical matter. The matter and its environment relevant to a particular case of energy transfer are classified as a system, and everything outside of that system is called the surroundings. For instance, when heating a pot of water on the stove, the system includes the stove, the pot, and the water. Energy is transferred within the system (between the stove, pot, and water). There are two types of systems: open and closed. An open system is one in which energy can be transferred between the system and its surroundings. The stovetop system is open because heat can be lost into the air. A closed system is one that cannot transfer energy to its surroundings. Biological organisms are open systems. Energy is exchanged between them and their surroundings, as they consume energystoring molecules and release energy to the environment by doing work. Like all things in the physical world, energy is subject to the laws of physics. The laws of thermodynamics govern the transfer of energy in and among all systems in the universe.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of tissue makes up the brain and the nerves that connect the brain to all parts of the body?","choices":["benign tissue","nervous tissue","neurotransmitters","peripheral tissue"],"answer":"B","rationale":"Nervous tissue is made up of neurons, or nerve cells, that carry electrical messages. Nervous tissue makes up the brain and the nerves that connect the brain to all parts of the body.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Periodic refers to something that does what?","choices":["fail","dies","falls","repeat"],"answer":"D","rationale":"Mendeleev\u2019s table of the elements is called a periodic table because of its repeating pattern. Anything that keeps repeating is referred to as periodic. Other examples of things that are periodic include the monthly phases of the moon and the daily cycle of night and day. The term period refers to the interval between repetitions. In a periodic table, the periods are the rows of the table. In Mendeleev\u2019s table, each period contains eight elements, and then the pattern repeats in the next row.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Blood is pumped from the heart, pushing open which valves?","choices":["aortic and carotid","pulmonary and respiratory","pulmonary and aortic semilunar","thoracic and aortic"],"answer":"C","rationale":"Ventricular Systole Ventricular systole (see Figure 19.27) follows the depolarization of the ventricles and is represented by the QRS complex in the ECG. It may be conveniently divided into two phases, lasting a total of 270 ms. At the end of atrial systole and just prior to atrial contraction, the ventricles contain approximately 130 mL blood in a resting adult in a standing position. This volume is known as the end diastolic volume (EDV) or preload. Initially, as the muscles in the ventricle contract, the pressure of the blood within the chamber rises, but it is not yet high enough to open the semilunar (pulmonary and aortic) valves and be ejected from the heart. However, blood pressure quickly rises above that of the atria that are now relaxed and in diastole. This increase in pressure causes blood to flow back toward the atria, closing the tricuspid and mitral valves. Since blood is not being ejected from the ventricles at this early stage, the volume of blood within the chamber remains constant. Consequently, this initial phase of ventricular systole is known as isovolumic contraction, also called isovolumetric contraction (see Figure 19.27). In the second phase of ventricular systole, the ventricular ejection phase, the contraction of the ventricular muscle has raised the pressure within the ventricle to the point that it is greater than the pressures in the pulmonary trunk and the aorta. Blood is pumped from the heart, pushing open the pulmonary and aortic semilunar valves. Pressure generated by the left ventricle will be appreciably greater than the pressure generated by the right ventricle, since the existing pressure in the aorta will be so much higher. Nevertheless, both ventricles pump the same amount of blood. This quantity is referred to as stroke volume. Stroke volume will normally be in the range of 70\u201380 mL. Since ventricular systole began with an EDV of approximately 130 mL of blood, this means that there is still 50\u201360 mL of blood remaining in the ventricle following contraction. This volume of blood is known as the end systolic volume (ESV).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term refers to a list of the elements that will replace the ones below them in single-replacement reactions?","choices":["activity series","growth series","Up series","probably series"],"answer":"A","rationale":"Chemical reactivity trends are easy to predict when replacing anions in simple ionic compounds\u2014simply use their relative positions on the periodic table. However, when replacing the cations, the trends are not as straightforward. This is partly because there are so many elements that can form cations; an element in one column on the periodic table may replace another element nearby, or it may not. A list called the activity series does the same thing the periodic table does for halogens: it lists the elements that will replace elements below them in single-replacement reactions. A simple activity series is shown below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What cause many human diseases by killing host cells or disturbing their homeostasis?","choices":["bacteria","cancer","parasites","viruses"],"answer":"D","rationale":"Viruses cause many human diseases by killing host cells or disturbing their homeostasis. Viruses are not affected by antibiotics. Several viral diseases can be treated with antiviral drugs or prevented with vaccines.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two types of digestive systems do invertebrates have?","choices":["slow or complete","fast or slow","incomplete or complete","unstable or complete"],"answer":"C","rationale":"Invertebrates have one of two types of digestive system: an incomplete or complete digestive system. Both are shown in Figure below . An incomplete digestive system consists of a digestive cavity with one opening. The single opening serves as both mouth and anus. A complete digestive system consists of a digestive tract with two openings. One opening is the mouth. The other is the anus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats?","choices":["amphibians","arthropods","mammals","reptiles"],"answer":"A","rationale":"Amphibians are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats.","split":"validation","source_dataset":"sciq","subject":null},{"question":"During exercise, the rate of blood returning to the heart does this?","choices":["reduces","remains stable","increases","changes randomly"],"answer":"C","rationale":"Correlation Between Heart Rates and Cardiac Output Initially, physiological conditions that cause HR to increase also trigger an increase in SV. During exercise, the rate of blood returning to the heart increases. However as the HR rises, there is less time spent in diastole and consequently less time for the ventricles to fill with blood. Even though there is less filling time, SV will initially remain high. However, as HR continues to increase, SV gradually decreases due to decreased filling time. CO will initially stabilize as the increasing HR compensates for the decreasing SV, but at very high rates, CO will eventually decrease as increasing rates are no longer able to compensate for the decreasing SV. Consider this phenomenon in a healthy young individual. Initially, as HR increases from resting to approximately 120 bpm, CO will rise. As HR increases from 120 to 160 bpm, CO remains stable, since the increase in rate is offset by decreasing ventricular filling time and, consequently, SV. As HR continues to rise above 160 bpm, CO actually decreases as SV falls faster than HR increases. So although aerobic exercises are critical to maintain the health of the heart, individuals are cautioned to monitor their HR to ensure they stay within the target heart rate range of between 120 and 160 bpm, so CO is maintained. The target HR is loosely defined as the range in which both the heart and lungs receive the maximum benefit from the aerobic workout and is dependent upon age.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the pattern of spacing among individuals within the boundaries of the population?","choices":["equilibrium","dispersion","diffusion","frequency"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What level is a feeding position in a food chain or web?","choices":["singular","trophic","neural","differentiation"],"answer":"B","rationale":"Each food chain or food web has organisms at different trophic levels. A trophic level is a feeding position in a food chain or web. The trophic levels are identified in the food web in Figure above . All food chains and webs have at least two or three trophic levels, but they rarely have more than four trophic levels. The trophic levels are:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do most of the noble gas elements have in common?","choices":["zero valence electrons","eight valence electrons","four valence electrons","two valence electrons"],"answer":"B","rationale":"Atoms can join together by forming a chemical bond, which is a very strong attraction between two atoms. Chemical bonds are formed when electrons in different atoms interact with each other to make an arrangement that is more stable than when the atoms are apart. What causes atoms to make a chemical bond with other atoms, rather than remaining as individual atoms? A clue comes by considering the noble gas elements, the rightmost column of the periodic table. These elements\u2014helium, neon, argon, krypton, xenon, and radon\u2014do not form compounds very easily, which suggests that they are especially stable as lone atoms. What else do the noble gas elements have in common? Except for helium, they all have eight valence electrons. Chemists have concluded that atoms are especially stable if they have eight electrons in their outermost shell. This useful rule of thumb is called the octet rule, and it is a key to understanding why compounds form.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the organisms that live in extreme conditions known as?","choices":["fibroblasts","extremophiles","naturophiles","carotenoids"],"answer":"B","rationale":"Many archaeans are extremophiles. Extremophiles are organisms that live in extreme conditions. For example, some archaeans live around hydrothermal vents. A hydrothermal vent is a crack on the ocean floor. You can see one in Figure below . Boiling hot, highly acidic water pours out of the vent. These extreme conditions don't deter archaeans. They have evolved adaptations for coping with them. These conditions are like those on ancient Earth. This suggests that archaeans may have evolved very early in Earth's history.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Collision frequency is greater for what category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'?","choices":["analogous","homogeneous","heterogeneous","contiguous"],"answer":"B","rationale":"Heterogeneous catalysts are easier to recover. Collision frequency is greater for homogeneous catalysts. Homogeneous catalysts are often more sensitive to temperature. Homogeneous catalysts are often more expensive. Saylor URL: http:\/\/www. saylor. org\/books.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does the pull of the moon's gravity on earth cause?","choices":["earthquakes","storms","tides","waves"],"answer":"C","rationale":"Figure below shows why tides occur. The main cause of tides is the pull of the Moon\u2019s gravity on Earth. The pull is greatest on whatever is closest to the Moon. Although the gravity pulls the land, only the water can move. As a result:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A water molecule forms when oxygen (o) and _______  atoms react and are held together by covalent bonds?","choices":["nitrogen","hydrogen (h)","carbon","steam"],"answer":"B","rationale":"An example of a chemical compound is water. A water molecule forms when oxygen (O) and hydrogen (H) atoms react and are held together by covalent bonds. Like other compounds, water always has the same chemical composition: a 2:1 ratio of hydrogen atoms to oxygen atoms. This is expressed in the chemical formula H 2 O. A model of a water molecule is shown in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What force makes objects seem lighter in water?","choices":["buoyant","resilient","surface tension","gravity"],"answer":"A","rationale":"Because of buoyant force, objects seem lighter in water. You may have noticed this when you went swimming and could easily pick up a friend or sibling under the water. Some of the person\u2019s weight was countered by the buoyant force of the water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What  is the process by which the nucleus of a eukaryotic cell divides?","choices":["meiosis","cytokinesis","mitosis","angiogenesis"],"answer":"C","rationale":"Mitosis is the process by which the nucleus of a eukaryotic cell divides. It happens in four phases: prophase, metaphase, anaphase, and telophase.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Iceland is made up of a series of?","choices":["glaciers","volcanoes","outcrops","earthquakes"],"answer":"B","rationale":"A fissure eruption on a volcano in Iceland. The lava flows downhill and turns snow into steam. Iceland is made of a set of volcanoes that are the result of a hotspot that lies on a mid-ocean ridge. The island is the only location where the mid-ocean ridge can be seen above sea level. Icelandic volcanoes have made the news lately since some have shut down air traffic in parts of Europe.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of organism does not need oxygen for growth and dies in its presence?","choices":["aerobic","symbiotic","anaerobic","acidic"],"answer":"C","rationale":"An anaerobic organism is any organism that does not need oxygen for growth and even dies in its presence. Obligate anaerobes will die when exposed to atmospheric levels of oxygen. Clostridium perfringens bacteria, which are commonly found in soil around the world, are obligate anaerobes. Infection of a wound by C. perfringens bacteria causes the disease gas gangrene. Obligate anaerobes use molecules other than oxygen as terminal electron acceptors.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells?","choices":["cochlea","alveoli","lymph nodes","edema glands"],"answer":"C","rationale":"eventually diffuses back into the capillaries near the venules. The remaining 15% of blood plasma drains out from the interstitial fluid into nearby lymphatic vessels (Figure 40.18). The fluid in the lymph is similar in composition to the interstitial fluid. The lymph fluid passes through lymph nodes before it returns to the heart via the vena cava. Lymph nodes are specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells. The white blood cells remove infectious agents, such as bacteria and viruses, to clean the lymph before it returns to the bloodstream. After it is cleaned, the lymph returns to the heart by the action of smooth muscle pumping, skeletal muscle action, and one-way valves joining the returning blood near the junction of the venae cavae entering the right atrium of the heart.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are hydrocarbons most important use?","choices":["lightsource","fuel","electricity","food"],"answer":"B","rationale":"Hydrocarbons have a wide variety of important uses, but their most important use is as fuels.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What protects tissues of the central nervous system from changes in ph?","choices":["sucrose ions","bicarbonate ions","fatty ions","cerebrum"],"answer":"B","rationale":"Bicarbonate ions play an important role in neutralizing acids throughout the body. Bicarbonate ions are especially important for protecting tissues of the central nervous system from changes in pH. The central nervous system includes the brain, which is the body\u2019s control center. If pH deviates too far from normal, the central nervous system cannot function properly. This can have a drastic effect on the rest of the body.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The air pressure is about 80% that of ________ pressure at sea level.","choices":["adverse atmospheric","standard atmospheric","internal atmospheric","specific atmospheric"],"answer":"B","rationale":"The air pressure is about 80% that of standard atmospheric pressure at sea level. For significant figure purposes, the standard pressure of 760 mmHg has three significant figures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Vertebrates - including fish, amphibians, reptiles, birds, and mammals - belong to what phylum?","choices":["nematota","chordata","animalia","angulata"],"answer":"B","rationale":"Vertebrates are animals in Phylum Chordata. Modern vertebrates include fish, amphibians, reptiles, birds, and mammals. You can see examples of all these groups of vertebrates in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"In our wildflower population, the pool of what remains constant from one generation to the next?","choices":["genes","genomes","DNA","eggs"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"When a membrane uses energy to move a substance across it, what kind of transport is this?","choices":["fast","inactive","active","slow"],"answer":"C","rationale":"x rms = 2Dt, where D is the diffusion constant, representative values of which are found in Table 12.2. \u2022 Osmosis is the transport of water through a semipermeable membrane from a region of high concentration to a region of low concentration. \u2022 Dialysis is the transport of any other molecule through a semipermeable membrane due to its concentration difference. \u2022 Both processes can be reversed by back pressure. \u2022 Active transport is a process in which a living membrane expends energy to move substances across it.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An electrostatic attraction between two ions that have exchanged what?","choices":["neutrons","electrons","quasars","protons"],"answer":"B","rationale":"An electrostatic attraction between two ions that have exchanged electrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"During what part of a person's development are they generally at their physical peak?","choices":["senility","early adulthood","late adulthood","infancy"],"answer":"B","rationale":"Early adulthood starts at age 18 or 21. It continues until the mid-30s. During early adulthood, people are at their physical peak. They are also usually in good health. The ability to have children is greatest during early adulthood, as well. This is the stage of life when most people complete their education. They are likely to begin a career or take a full-time job. Many people also marry and start a family during early adulthood.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of movement involves sluggish segmentation, primarily in the transverse and descending colons?","choices":["haustral contraction","gasutral contraction","photoreactive contraction","accompanying contraction"],"answer":"A","rationale":"Mechanical Digestion In the large intestine, mechanical digestion begins when chyme moves from the ileum into the cecum, an activity regulated by the ileocecal sphincter. Right after you eat, peristalsis in the ileum forces chyme into the cecum. When the cecum is distended with chyme, contractions of the ileocecal sphincter strengthen. Once chyme enters the cecum, colon movements begin. Mechanical digestion in the large intestine includes a combination of three types of movements. The presence of food residues in the colon stimulates a slow-moving haustral contraction. This type of movement involves sluggish segmentation, primarily in the transverse and descending colons. When a haustrum is distended with chyme, its muscle contracts, pushing the residue into the next haustrum. These contractions occur about every 30 minutes, and each last about 1 minute. These movements also mix the food residue, which helps the large intestine absorb water. The second type of movement is peristalsis, which, in the large intestine, is slower than in the more proximal portions of the alimentary canal. The third type is a mass movement. These strong waves start midway through the transverse colon and quickly force the contents toward the rectum. Mass movements usually occur three or four times per day, either while you eat or immediately afterward. Distension in the stomach and the breakdown products of digestion in the small intestine provoke the gastrocolic reflex, which increases motility, including mass movements, in the colon. Fiber in the diet both softens the stool and increases the power of colonic contractions, optimizing the activities of the colon.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Vertebrates evolved from primitive forms of which creature?","choices":["cephalopods","gastropods","chordates","eukaryotes"],"answer":"C","rationale":"Vertebrates evolved from primitive chordates. This occurred about 550 million years ago. The earliest vertebrates may have been jawless fish, like the hagfish in Figure below . Vertebrates evolved a backbone to replace the notochord after the embryo stage. They also evolved a cranium, or bony skull, to enclose and protect the brain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does the aqueous fluid between the chloroplast membrane and the grana known as?","choices":["plasma","water","blood","stroma"],"answer":"D","rationale":"Both chloroplasts and photosynthetic bacteria contain grana, neat stacks of flattened sac-shaped membrane compartments called thylakoids . Thylakoids can be considered a sub-organelle within the chloroplast. Between the chloroplast membrane and the grana is an aqueous fluid known as stroma . Thylakoids, especially the thylakoid membrane, organize patterns of proteins and other molecules which conduct photosynthesis, as shown in Figure below . In addition to enzymes, two basic types of molecules - pigments and electron carriers \u2013 are significant in this process. You can take a video tour of a chloroplast at Encyclopedia Britannica: Chloroplast : http:\/\/www. britannica. com\/EBchecked\/media\/16440\/Chloroplasts-circulate-within-plant-cells .","split":"validation","source_dataset":"sciq","subject":null},{"question":"When a hypothesis is repeatedly confirmed, what can it then become?","choices":["study","evolution","theory","Thesis"],"answer":"C","rationale":"When a hypothesis is confirmed repeatedly, it eventually becomes a theory \u2013 a general principle that is offered to explain natural phenomena. Note a key word \u2013 explanation. The theory offers a description of why something happens. A law, on the other hand, is a statement that is always true, but does not explain why. The law of gravity says a rock will fall when dropped, but does not explain why (gravitational theory is very complex and incomplete at present). The kinetic-molecular theory of gases, on the other hand, tells what happens when a gas is heated in a closed container (the pressure increases), but also explains why (the motions of the gas molecules are increased due to the change in temperature). Theories do not get \u201cpromoted\u201d to laws because laws do not answer the \u201cwhy\u201d question.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Using a hammer to remove a nail changes both the direction and strength of the what?","choices":["applied force","static energy","gravity","kinetic energy"],"answer":"A","rationale":"Using a hammer to remove a nail changes both the direction and strength of the applied force. Where is the fulcrum of the hammer when it is used in this way?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Through which process are plants able to make their own food?","choices":["metabolism","cell division","glycolysis","photosynthesis"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of waves are sound waves?","choices":["spinning","mechanical","internal","External"],"answer":"B","rationale":"A: It wouldn\u2019t unless the vibrations were carried by another medium. Sound waves are mechanical waves, so they can travel only though matter and not through empty space.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The protein without the prosthetic group is known as the what?","choices":["spicule","monoprotein","xerophyte","apoprotein"],"answer":"D","rationale":"As we will return to later, proteins are functional entities, composed of polypeptides and prosthetic group. The prosthetic group is essential for normal protein function. The protein without the prosthetic group is known as the apoprotein. biofundamentals \u2013 coreBIO.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What connections allow heterocysts to transport fixed nitrogen to neighboring cells and to receive carbohydrates?","choices":["neurons","peptide","heterogeneity","intercellular"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The classes anthozoa, scyphozoa, cubozoa, and hydrozoa make up what phylum?","choices":["cnidaria","mollusca","crinoids","poriferia"],"answer":"A","rationale":"differentiated cell types in each tissue layer, such as nerve cells, enzyme-secreting cells, and nutrient-absorbing cells, as well as intercellular connections between the cells. However, organs and organ systems are not present in this phylum. The nervous system is primitive, with nerve cells scattered across the body in a network. The function of the nerve cells is to carry signals from sensory cells and to contractile cells. Groups of cells in the nerve net form nerve cords that may be essential for more rapid transmission. Cnidarians perform extracellular digestion, with digestion completed by intracellular digestive processes. Food is taken into the gastrovascular cavity, enzymes are secreted into the cavity, and the cells lining the cavity absorb the nutrient products of the extracellular digestive process. The gastrovascular cavity has only one opening that serves as both a mouth and an anus (an incomplete digestive system). Like the sponges, Cnidarian cells exchange oxygen, carbon dioxide, and nitrogenous wastes by diffusion between cells in the epidermis and gastrodermis with water. Cnidarian Diversity The phylum Cnidaria contains about 10,000 described species divided into four classes: Anthozoa, Scyphozoa, Cubozoa, and Hydrozoa. The class Anthozoa includes all cnidarians that exhibit a sessile polyp body plan only; in other words, there is no medusa stage within their life cycle. Examples include sea anemones, sea pens, and corals, with an estimated number of 6,100 described species. Sea anemones are usually brightly colored and can attain a size of 1.8 to 10 cm in diameter. These animals are usually cylindrical in shape and are attached to a substrate. A mouth opening is surrounded by tentacles bearing cnidocytes (Figure 15.12).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where does waste enter the large intestine from?","choices":["the small intestine","kidneys","the small tissue","liver"],"answer":"A","rationale":"The large intestine is a wide tube that connects the small intestine with the anus. In adults, it is about five feet long. Waste enters the large intestine from the small intestine in a liquid state. As the waste moves through the large intestine, excess water is absorbed from it. After the excess water is absorbed, the remaining solid waste is called feces.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do different soil horizons show different amounts of?","choices":["evolution","alteration","distortion","secretion"],"answer":"B","rationale":"Soil horizons are layers within a soil. Different soil horizons show different amounts of alteration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the main source of energy for your body?","choices":["vitamins","proteins","carbohydrates","fats"],"answer":"C","rationale":"Carbohydrates, proteins, and lipids are categories of organic compounds. They give your body energy, though carbohydrates are the main source of energy. Proteins provide building materials, such as amino acids to build your own proteins. Proteins, vitamins, and minerals also help control body processes. Carbohydrates include sugars such as the glucose made by photosynthesis. Often glucose is stored in large molecules such as starch. Proteins are found in foods like meats and nuts. Lipids includes fats and oils. Though you should stay away from many types of fats, others are needed by your body. Important vitamins include vitamins A, B (multiple types) C, D, and E. Important minerals include calcium and potassium. What should you drink to get calcium? Milk is a good source.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are thin, very small tail-like projections that extend outward from the cell body that allow protists to move?","choices":["cilia","notochords","fins","antennae"],"answer":"A","rationale":"The ciliates are protists that move by using cilia. Cilia are thin, very small tail-like projections that extend outward from the cell body. Cilia beat back and forth, moving the protist along. Paramecium has cilia that propel it.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Earthquakes, which may occur on california\u2019s abundant faults, can also trigger what?","choices":["Waves","landslides","avalanches","floods"],"answer":"B","rationale":"Some communities have developed landslide warning systems. Around San Francisco Bay, the National Weather Service and the U. S. Geological Survey use rain gauges to monitor soil moisture. If soil becomes saturated, the weather service issues a warning. Earthquakes, which may occur on California\u2019s abundant faults, can also trigger landslides.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In which way do particles of water move in deep water?","choices":["parabolas","currents","circles","ellipses"],"answer":"C","rationale":"In deep water, particles of water just move in circles. They don\u2019t actually move closer to shore with the energy of the waves. However, near the shore where the water is shallow, the waves behave differently. They start to drag on the bottom, creating friction (see Figure below ). The friction slows down the bottoms of the waves, while the tops of the waves keep moving at the same speed. This causes the waves to get steeper until they topple over and crash on the shore. The crashing waves carry water onto the shore as surf.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the study of heat engines?","choices":["Chemical dynamics","chemistry","biology","thermodynamics"],"answer":"D","rationale":"Thermodynamics is the study of heat engines. Any engine or power plant obeys the laws of thermodynamics. The first law of thermodynamics is a statement of conservation of energy. Total energy, including heat, is conserved in any process and in the complete cycle of a heat engine. The second law of thermodynamics as it applies to heat engines gives an absolute limit on the efficiency of any heat engine that goes through repetitious cycles.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Mechanical waves can only trave through what?","choices":["air","light","matter","water"],"answer":"C","rationale":"The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium ( plural , media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center and of what shape?","choices":["convex","asymmetrical","square","concave"],"answer":"D","rationale":"Discussion The negative power indicates a diverging (or concave) lens, as expected. The spectacle produces a case 3 image closer to the eye, where the person can see it. If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center. Additionally, if you examine a prescription for eyeglasses for nearsighted people, you will find that the prescribed power is negative and given in units of diopters.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call air flowing over earth\u2019s surface?","choices":["gas","air pressure","steam","wind"],"answer":"D","rationale":"Air always flows from an area of higher pressure to an area of lower pressure. Air flowing over Earth\u2019s surface is called wind . The greater the difference in pressure, the stronger the wind blows.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What three particles make up most atoms?","choices":["protons, electrons and nucleus","micrometres , electrons and neutrons","neutrons, protons and radii","protons, electrons and neutrons"],"answer":"D","rationale":"A neutron is one of three main particles that make up the atom. The other two particles are the proton and electron. Atoms of all elements\u2014except for most atoms of hydrogen\u2014have neutrons in their nucleus. The nucleus is the small, dense region at the center of an atom where protons are also found. Atoms generally have about the same number of neutrons as protons. For example, all carbon atoms have six protons and most also have six neutrons. A model of a carbon atom is shown in the Figure below . For an excellent video explaining the structure of atoms, including neutrons, go to this URL:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How can one dimensional vectors be added?","choices":["exponentially","incrementally","sequentially","arithmetically"],"answer":"D","rationale":"Vectors that are in one dimension can be added arithmetically.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is caused by the reaction of nonmetal oxides with water in the atmosphere?","choices":["yellow rain","acid rain","ozone rain","carbon rain"],"answer":"B","rationale":"Acid rain is caused by the reaction of nonmetal oxides with water in the atmosphere. One such reaction involves nitrogen dioxide (NO2) and produces nitric acid (HNO3): 3NO2 + H2O \u2192 2HNO3 + NO If 1.82 \u00d7 1013 g of NO2 enter the atmosphere every year due to human activities, potentially how many grams of HNO3 can be produced annually?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Into how many basic regions can the aquatic biome be broken down?","choices":["six","two","five","One"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The top of the saturated rock layer is called what?","choices":["sand layer","water table","calcified layer","compressed layer"],"answer":"B","rationale":"The top of the saturated rock layer above ( Figure above ) is called the water table . The water table isn\u2019t like a real table. It doesn\u2019t remain firmly in one place. Instead, it rises or falls, depending on how much water seeps down from the surface. The water table is higher when there is a lot of rain, and it is lower when the weather is dry.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which field studies how to tailor medical treatments to our genetic profiles?","choices":["metagenomics","immunology","pharmacogenomics","proteomics"],"answer":"C","rationale":"We know that, thanks to our DNA, each of us is a little bit different. Some of those differences are obvious, like eye and hair color. Others are not so obvious, like how our bodies react to medication. Researchers are beginning to look at how to tailor medical treatments to our genetic profiles, in a relatively new field called pharmacogenomics . Some of the biggest breakthroughs have been in cancer treatment. For additional information on this \u201cpersonalized medicine,\u201d listen to http:\/\/www. kqed. org\/quest\/radio\/personalized-medicine and see http:\/\/www. kqed. org\/quest\/blog\/2009\/09\/11\/reporters-notes-personalized-medicine\/ .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Research that focuses on understanding basic properties and processes without concern for the usefulness of this understanding is known as what kind of research?","choices":["applied research","pure research","disconnected research","focused research"],"answer":"B","rationale":"Pure research focuses on understanding basic properties and processes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cells of what category of organisms can be organized at the level of cells, tissues, organs, and organ systems?","choices":["multicellular","biomolecular","intricate","complex"],"answer":"A","rationale":"Cells can exist independently as single-celled organisms or with other cells as multicellular organisms. Cells of a multicellular organism can be organized at the level of cells, tissues, organs, and organ systems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What property of materials describes the ease in which they can be molded into thin sheets?","choices":["rigidity","malleability","plasticity","permeability"],"answer":"B","rationale":"A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. Silver is a shiny metal that conducts electricity very well. It can be molded into thin sheets, a property called malleability. Salt is dull and brittle and conducts electricity when it has been dissolved into water, which it does quite easily. Physical properties of matter include color, hardness, malleability, solubility, electrical conductivity, density, melting points , and boiling points .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call materials that have low resistance to electric current?","choices":["electric conductors","electromagnets","poor conductors","good insulator"],"answer":"A","rationale":"Materials that have low resistance to electric current are called electric conductors . Many metals\u2014including copper, aluminum, and steel\u2014are good conductors of electricity. The outer electrons of metal atoms are loosely bound and free to move, allowing electric current to flow. Water that has even a tiny amount of impurities is an electric conductor as well.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the transfer of heat by a current?","choices":["radiation","diffusion","convection","conduction"],"answer":"C","rationale":"Convection is the transfer of heat by a current. Convection happens in a liquid or a gas. Air near the ground is warmed by heat radiating from Earth's surface. The warm air is less dense, so it rises. As it rises, it cools. The cool air is dense, so it sinks to the surface. This creates a convection current ( Figure below ). Convection is the most important way that heat travels in the atmosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Arterioles receive blood from arteries, which are vessels with a much larger lumen. as their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down\u2014or resisting\u2014blood flow. the arterioles can also constrict or dilate, which varies their what?","choices":["resistance","osmosis","advantage","gravity"],"answer":"A","rationale":"Chapter 20 1 Water. 3 A 5 C 7 C 9 A 11 D 13 B 15 A 17 C 19 A 21 C 23 D 25 D 27 C 28 Arterioles receive blood from arteries, which are vessels with a much larger lumen. As their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down\u2014or resisting\u2014blood flow. The arterioles can also constrict or dilate, which varies their resistance, to help distribute blood flow to the tissues. 30 This is a venule. 32 People who stand upright all day and are inactive overall have very little skeletal muscle activity in the legs. Pooling of blood in the legs and feet is common. Venous return to the heart is reduced, a condition that in turn reduces cardiac output and therefore oxygenation of tissues throughout the body. This could at least partially account for the patient\u2019s fatigue and shortness of breath, as well as her \u201cspaced out\u201d feeling, which commonly reflects reduced oxygen to the brain. 34 False. The plasma proteins suspended in blood cannot cross the semipermeable capillary cell membrane, and so they remain in the plasma within the vessel, where they account for the blood colloid osmotic pressure. 36 Nitric oxide is a very powerful local vasodilator that is important in the autoregulation of tissue perfusion. If it were not broken down very quickly after its release, blood flow to the region could exceed metabolic needs. 38 The gonadal veins drain the testes in males and the ovaries in females. 40 Angiogenesis inhibitors are drugs that inhibit the growth of new blood vessels. They can impede the growth of tumors by limiting their blood supply and therefore their access to gas and nutrient exchange.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the circular center of a hurricane better known as?","choices":["the nose","the eye","the epicenter","the focus"],"answer":"B","rationale":"At the center of a hurricane is a small area where the air is calm and clear. This is called the eye of the hurricane ( Figure below ). The eye forms at the low-pressure center of the hurricane. Air in the eye rises upward.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Are most glaciers currently growing or shrinking?","choices":["growing","shrinking","freezing","no change"],"answer":"B","rationale":"Glaciers are not static; they grow, they move and they shrink. Currently, most glaciers are shrinking.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of model - which includes producers, consumers and decomposers - shows the interactions between organisms across trophic levels?","choices":["interdepence web","organic web","food web","fuel web"],"answer":"C","rationale":"Figure 20.6 This food web shows the interactions between organisms across trophic levels. Arrows point from an organism that is consumed to the organism that consumes it. All the producers and consumers eventually become nourishment for the decomposers (fungi, mold, earthworms, and bacteria in the soil). (credit \"fox\": modification of work by Kevin Bacher, NPS; credit \"owl\": modification of work by John and Karen Hollingsworth, USFWS; credit \"snake\": modification of work by Steve Jurvetson; credit \"robin\": modification of work by Alan Vernon; credit \"frog\": modification of work by Alessandro Catenazzi; credit \"spider\": modification of work by \"Sanba38\"\/Wikimedia Commons; credit \"centipede\": modification of work by \u201cBauerph\u201d\/Wikimedia Commons; credit \"squirrel\": modification of work by Dawn Huczek; credit \"mouse\": modification of work by NIGMS, NIH; credit \"sparrow\": modification of work by David Friel; credit \"beetle\": modification of work by Scott Bauer, USDA Agricultural Research Service; credit \"mushrooms\": modification of work by Chris Wee; credit \"mold\": modification of work by Dr. Lucille Georg, CDC; credit \"earthworm\": modification of work by Rob Hille; credit \"bacteria\": modification of work by Don Stalons, CDC).","split":"validation","source_dataset":"sciq","subject":null},{"question":"The multifidus muscle of the lumbar region helps extend and laterally flex this?","choices":["vertebal column","knee","forearm","pelvic muscle"],"answer":"A","rationale":"are associated. The semispinalis muscles include the semispinalis capitis, the semispinalis cervicis, and the semispinalis thoracis. The multifidus muscle of the lumbar region helps extend and laterally flex the vertebral column. Important in the stabilization of the vertebral column is the segmental muscle group, which includes the interspinales and intertransversarii muscles. These muscles bring together the spinous and transverse processes of each consecutive vertebra. Finally, the scalene muscles work together to flex, laterally flex, and rotate the head. They also contribute to deep inhalation. The scalene muscles include the anterior scalene muscle (anterior to the middle scalene), the middle scalene muscle (the longest, intermediate between the anterior and posterior scalenes), and the posterior scalene muscle (the smallest, posterior to the middle scalene).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does k stand for on the periodic table?","choices":["magnesium","aluminum","potassium","calcium"],"answer":"C","rationale":"Q: The table shown in the Figure above is called the periodic table of the elements. Each symbol stands for a different element. What do you think the symbol K stands for?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Beta decay occurs when a nucleus has too few of what relative to protons?","choices":["protons","nuclei","electrons","neutrons"],"answer":"D","rationale":"Beta decay occurs when a nucleus is unstable because it has too many or too few neutrons relative to protons. The nucleus emits a beta particle and energy. A beta particle is either an electron (beta-minus decay) or a positron (beta-plus decay).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Trees have woody stems covered with what?","choices":["larvae","shells","rust","bark"],"answer":"D","rationale":"Trees have woody stems covered with bark.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What prevents an object from moving in a straight line at a constant speed?","choices":["friction","force","matter","weight"],"answer":"B","rationale":"Newton\u2019s first law implies that an object oscillating back and forth is experiencing forces. Without force, the object would move in a straight line at a constant speed rather than oscillate. Consider, for example, plucking a plastic ruler to the left as shown in Figure 16.2. The deformation of the ruler creates a force in the opposite direction, known as a restoring force. Once released, the restoring force causes the ruler to move back toward its stable equilibrium position, where the net force on it is zero. However, by the time the ruler gets there, it gains momentum and continues to move to the right, producing the opposite deformation. It is then forced to the left, back through equilibrium, and the process is repeated until dissipative forces dampen the motion. These forces remove mechanical energy from the system, gradually reducing the motion until the ruler comes to rest. The simplest oscillations occur when the restoring force is directly proportional to displacement. When stress and strain were covered in Newton\u2019s Third Law of Motion, the name was given to this relationship between force and displacement was Hooke\u2019s law:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The effect of acetylcholine in heart muscle is inhibitory rather than what?","choices":["olfactory","excitatory","neurotransmitter","exofactory"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the division of the cytoplasm in eukaryotic cells?","choices":["cytokinesis","metamorphosis","andronisis","electrolysis"],"answer":"A","rationale":"The second major step is cytokinesis . As in prokaryotic cells, the cytoplasm must divide. Cytokinesis is the division of the cytoplasm in eukaryotic cells, resulting in two genetically identical daughter cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The white of an egg becomes opaque when cooked because what are insoluble and solidify?","choices":["fatty acids","calcium molecules","acetic proteins","denatured proteins"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of plants lack xylem or phloem to transport nutrients, water, and food?","choices":["trichina","nonvascular","single-celled","spicule"],"answer":"B","rationale":"Nonvascular plants evolved first. They are distinct from the algae because they keep the embryo inside of the reproductive structure after fertilization. These plants do not have vascular tissue, xylem or phloem, to transport nutrients, water, and food. Examples include mosses, liverworts, and hornworts. Without vascular tissue, these plants do not grow very tall.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Exemplified by baring teeth, what type of displays are common in the animal kingdom, and sometimes serve as a 'bluff'?","choices":["aggressive","passive","defensive","sexual"],"answer":"A","rationale":"incorrectly or a proper response is not given, the mating ritual is abandoned and the mating attempt will be unsuccessful. The mating display of the common stork is shown in Figure 45.37. Aggressive displays are also common in the animal kingdom. An example is when a dog bares its teeth when it wants another dog to back down. Presumably, these displays communicate not only the willingness of the animal to fight, but also its fighting ability. Although these displays do signal aggression on the part of the sender, it is thought that these displays are actually a mechanism to reduce the amount of actual fighting that occurs between members of the same species: they allow individuals to assess the fighting ability of their opponent and thus decide whether it is \u201cworth the fight. \u201d The testing of certain hypotheses using game theory has led to the conclusion that some of these displays may overstate an animal\u2019s actual fighting ability and are used to \u201cbluff\u201d the opponent. This type of interaction, even if \u201cdishonest,\u201d would be favored by natural selection if it is successful more times than not.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The preferred phase a substance adopts can change with temperature. at low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). as the temperature increases, those substances with very weak intermolecular forces become gases directly in a process called this?","choices":["sublimation","vaporization","Freezing Point","speciation"],"answer":"A","rationale":"The preferred phase a substance adopts can change with temperature. At low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). As the temperature increases, those substances with very weak intermolecular forces become gases directly (in a process called sublimation, which will be discussed in Section 10.2 \"Phase Transitions: Melting, Boiling, and Subliming\"). Substances with weak interactions can become liquids as the temperature increases. As the temperature increases even more, the individual particles will have so much energy that the intermolecular forces are overcome, so the particles separate from each other, and the substance becomes a gas (assuming that their chemical bonds are not so weak that the compound decomposes from the high temperature). Although is it difficult to predict the temperature ranges for which solid, liquid, or gas is the preferred phase for any random substance, all substances progress from solid to liquid to gas in that order as temperature increases.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What pigment do slow fibers contain?","choices":["melolin","myoglobin","hemoglobin","iron"],"answer":"B","rationale":"Which of the following statements is true? a. Fast fibers have a small diameter. Fast fibers contain loosely packed myofibrils. Fast fibers have large glycogen reserves. Fast fibers have many mitochondria. Which of the following statements is false? a. Slow fibers have a small network of capillaries. Slow fibers contain the pigment myoglobin. Slow fibers contain a large number of mitochondria. Slow fibers contract for extended periods. Cardiac muscles differ from skeletal muscles in that they ________. are striated b. utilize aerobic metabolism.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are clathrin, copi and copii types of?","choices":["replication coats","pathogen coats","artery coats","vesicle coats"],"answer":"D","rationale":"The vesicle coat selects specific proteins as cargo. It selects cargo proteins by binding to sorting signals. These complexes cluster in the membrane, forming a vesicle buds, or coated pit . There are three types of vesicle coats: clathrin , COPI and COPII. Clathrin coats are found on vesicles trafficking between the Golgi and plasma membrane, the Golgi and endosomes, and the plasma membrane and endosomes. COPI ( coat protein complex) coated vesicles are responsible for transport from the cis -Golgi to the ER (retrograde transport), while COPII coated vesicles are responsible for transport from the ER to the Golgi (anterograde transport). Low-density lipoprotein (LDL) receptors aggregate in clathrin coated pits prior to internalization.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for the force that attracts water molecules to other polar substances?","choices":["adhesion","aeration","osmosis","diffusion"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"All alkaline earth metals have similar properties because they all have two what?","choices":["valence electrons","caesium electrons","balanced electrons","transitions electrons"],"answer":"A","rationale":"All alkaline Earth metals have similar properties because they all have two valence electrons. They readily give up their two valence electrons to achieve a full outer energy level, which is the most stable arrangement of electrons. As a result, they are very reactive, although not quite as reactive as the alkali metals in group 1. For example, alkaline Earth metals will react with cold water, but not explosively as alkali metals do. Because of their reactivity, alkaline Earth metals never exist as pure substances in nature. Instead, they are always found combined with other elements.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A solenoid or coil wrapped around iron or certain other metals can form what kind of magnet?","choices":["superconductor","electromagnet","polarized magnet","permanent magnet"],"answer":"B","rationale":"An electromagnet is a solenoid wrapped around a bar of iron or other ferromagnetic material. The magnetic field of the solenoid magnetizes the iron bar.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Is the yolk more or less concentrated toward the animal pole?","choices":["more concentrated","same concentrated","less concentrated","no change"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the location where bones come together?","choices":["fingers","Knees","joints","muscles"],"answer":"C","rationale":"The adult human body has 206 bones, and with the exception of the hyoid bone in the neck, each bone is connected to at least one other bone. Joints are the location where bones come together. Many joints allow for movement between the bones. At these joints, the articulating surfaces of the adjacent bones can move smoothly against each other. However, the bones of other joints may be joined to each other by connective tissue or cartilage. These joints are designed for stability and provide for little or no movement. Importantly, joint stability and movement are related to each other. This means that stable joints allow for little or no mobility between the adjacent bones. Conversely, joints that provide the most movement.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term denotes lower levels of exposure, for instance to radiation, over a longer period of time?","choices":["chronic exposure","non-exposure","excess exposure","recent exposure"],"answer":"A","rationale":"Exposure gives an indication of the amount of radiation that travels through the air. Two factors influence the amount of exposure a person may receive \u2013 time and intensity. Acute exposure indicates a large amount of radiation received over a short period of time. Chronic exposure deals with lower levels of exposure over a longer period of time. Dose equivalence combines the amount of radiation received and the medical effect of that radiation. Calculations of exposure and dose equivalence are complicated and will not be pursued at this time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What causes water molecules to stay close to each other?","choices":["hydrogen bonding","surface tension","friction","oxidation"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the main cause of recent global warming?","choices":["solar flares","ice ages","human beings","insect overpopulation"],"answer":"C","rationale":"Natural processes caused earlier climate changes. Human beings are the main cause of recent global warming.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In solids, particles can't overcome the force of attraction between them because they lack what?","choices":["momentum","residual energy","gravity","kinetic energy"],"answer":"D","rationale":"In solids, particles don\u2019t have enough kinetic energy to overcome the force of attraction between them. The particles are packed closely together and cannot move around. All they can do is vibrate. This explains why solids have a fixed volume and shape.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the organelles where the process of photosynthesis takes place in plants and algae.","choices":["ribosomes","mitochondria","chloroplasts","fibroblasts"],"answer":"C","rationale":"Chloroplasts are the organelles where the process of photosynthesis takes place in plants and algae.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What process occurs when two alleles are expressed equally in the phenotype of the heterozygote?","choices":["fertilization","pollenation","codominance","codependence"],"answer":"C","rationale":"Codominance occurs when both alleles are expressed equally in the phenotype of the heterozygote. The red and white flower in the figure has codominant alleles for red petals and white petals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Magnetic poles always occur in pairs - what are the names of each pole?","choices":["tropic and arctic","north and south","southwest and south","prime and equator"],"answer":"B","rationale":"\u2022 Like poles repel and unlike poles attract. \u2022 Magnetic poles always occur in pairs of north and south\u2014it is not possible to isolate north and south poles.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Anemia is a disease that affects what?","choices":["brain","kidney","blood","heart"],"answer":"C","rationale":"Red meat, legumes, and spinach are all good sources of iron. Getting enough iron in your diet is important to prevent anemia. Anemia is a blood disease that causes you to feel weak and tired. Although anemia is caused by a nutrient deficiency, other blood diseases are genetic diseases, or forms of cancer.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The end of a pine tree branch bears the male cones that produce what?","choices":["pollen","flowers","spores","needles"],"answer":"A","rationale":"The end of a pine tree branch bears the male cones that produce the pollen.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the material inside the cell membrane called?","choices":["cytoplasm","mucus","chloroplasm","cerebellum"],"answer":"A","rationale":"Cytoplasm is the material inside the cell membrane. It includes a watery substance called cytosol. Besides water, cytosol contains enzymes and other substances. Cytoplasm also includes other cell structures suspended in the cytosol.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The energy stored in the organic molecules of food ultimately comes from where?","choices":["earth","sun","ocean","plant"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sulfur dioxide produced by burning coal is the leading cause of what deadly phenomenon?","choices":["hail","carbon rain","acid rain","dioxide rain"],"answer":"C","rationale":"Another problem with coal is that most coal contains sulfur. As it burns, the sulfur goes into the air as sulfur dioxide. Sulfur dioxide is the main cause of acid rain. Acid rain can be deadly to plants, animals, and whole ecosystems. Burning coal also puts a large number of small solid particulates into the air. These particles are dangerous to people, especially those who have asthma. People with asthma may end up in the hospital on days when particulate pollution is high.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When an eagle, a land eater, goes and gets fish from the sea, as well, its called?","choices":["descending food web","food chain mixing","overlapping food source","overlapping food web"],"answer":"D","rationale":"Food webs also overlap. For example, an eagle is part of a land food web. But it might go to the sea to grab a fish. That fish is part of a marine food web.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where the axon emerges from the cell body, there is a special region referred to as the what?","choices":["dendrite","axosomatic synapse","cellular hillock","axon hillock"],"answer":"D","rationale":"Where the axon emerges from the cell body, there is a special region referred to as the axon hillock. This is a tapering of the cell body toward the axon fiber. Within the axon hillock, the cytoplasm changes to a solution of limited components called axoplasm. Because the axon hillock represents the beginning of the axon, it is also referred to as the initial segment. Many axons are wrapped by an insulating substance called myelin, which is actually made from glial cells. Myelin acts as insulation much like the plastic or rubber that is used to insulate electrical wires. A key difference between myelin and the insulation on a wire is that there are gaps in the myelin covering of an axon. Each gap is called a node of Ranvier and is important to the way that electrical signals travel down the axon. The length of the axon between each gap, which is wrapped in myelin, is referred to as an axon segment. At the end of the axon is the axon terminal, where there are usually several branches extending toward the target cell, each of which ends in an enlargement called a synaptic end bulb. These bulbs are what make the connection with the target cell at the synapse.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The specialized study of the motion of objects that are atomic\/subatomic in size is called what?","choices":["string theory","enthalpy","atomic mechanics","quantum mechanics"],"answer":"D","rationale":"The study of motion of large objects such as baseballs is called mechanics, or more specifically classical mechanics. Because the quantum nature of the electron and other tiny particles moving at high speeds, classical mechanics is inadequate to accurately describe their motion. Quantum mechanics is the study of the motion of objects that are atomic or subatomic in size and thus demonstrate wave-particle duality. In classical mechanics, the size and mass of the objects involved effectively obscures any quantum effects so that such objects appear to gain or lose energies in any amounts. Particles whose motion is described by quantum mechanics gain or lose energy in the small pieces called quanta .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Circadian rhythms and migration are examples of which behaviors?","choices":["natural","cyclic","periodic","regular"],"answer":"B","rationale":"Types of animal behavior include cyclic behaviors such as circadian rhythms and migration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Acids are classified based on their what?","choices":["ionization in water","reaction to gas","solvency","diffusion in water"],"answer":"A","rationale":"Acids are classified as either strong or weak, based on their ionization in water. A strong acid is an acid which is completely ionized in an aqueous solution. Hydrogen chloride (HCl) ionizes completely into hydrogen ions and chloride ions in water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of muscle enables the body to move?","choices":["Sartorius","gluteus maximus","Latissimus Dorsi","skeletal muscle"],"answer":"D","rationale":"Human Skeletal Muscles. Skeletal muscles enable the body to move.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What results when volcanic ash encircles the globe, blocking the sun and lowering the temperature of the entire planet?","choices":["volcanic freeze","seismic apocalypse","volcanic winter","seismic winter"],"answer":"C","rationale":"Supervolcanoes are the most dangerous type of volcano. During an eruption, enormous amounts of ash are thrown into the atmosphere. The ash encircles the globe. This blocks the Sun and lowers the temperature of the entire planet. The result is a volcanic winter.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Oxygen and glucose are both reactants in the process of","choices":["reproduction","cellular respiration","death","birth"],"answer":"B","rationale":"Oxygen and glucose are both reactants in the process of cellular respiration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why does the moon evolve around the earth rather than the sun?","choices":["weaker gravitational force","stronger planetary force","stronger magnetic force","stronger gravitational force"],"answer":"D","rationale":"Objects that are closer together have a stronger force of gravity. For example, the moon is closer to Earth than it is to the more massive sun, so the force of gravity is greater between the moon and Earth than between the moon and the sun. That\u2019s why the moon circles around Earth rather than the sun. This is illustrated in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is an area in a body of water where nothing grows because there is too little oxygen known as?","choices":["dead zone","missing zone","cold zone","deceased zone"],"answer":"A","rationale":"Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. The nitrogen is a fertilizer in the water bodies. Since there is a lot of nitrogen it causes algae to grow out of control. Figure below shows a pond covered with algae. Algae may use up so much oxygen in the water that nothing else can grow. Soon, even the algae die out. Decomposers break down the dead tissue and use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico. You can see it Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Most air pollutants can be traced to what source ?","choices":["ozone leaks","methane","fossil fuels","chemical pollution"],"answer":"C","rationale":"Most air pollutants can be traced to the burning of fossil fuels. Fossil fuels are burned during many processes, including in power plants to create electricity, in factories to make machinery run, in power stoves and furnaces for heating, and in waste facilities. Perhaps one of the biggest uses of fossil fuels is in transportation. Fossil fuels are used in cars, trains, and planes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A species become separated and becomes two separate species. what can they not do anymore?","choices":["eat","grow","defecate","breed"],"answer":"D","rationale":"Assume that some members of a species become geographically separated from the rest of the species. If they remain separated long enough, they may evolve genetic differences. If the differences prevent them from interbreeding with members of the original species, they have evolved into a new species. Speciation that occurs in this way is called allopatric speciation . An example is described in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"A phase diagram plots pressure and what else?","choices":["precipitation","oxygen","temperature","volume"],"answer":"C","rationale":"Summary The states of matter exhibited by a substance under different temperatures and pressures can be summarized graphically in a phase diagram, which is a plot of pressure versus temperature. Phase diagrams contain discrete regions corresponding to the solid, liquid, and gas phases. The solid and liquid regions are separated by the melting curve of the substance, and the liquid and gas regions are separated by its vapor pressure curve, which ends at the critical point. Within a given region, only a single phase is stable, but along the lines that separate the regions, two phases are in equilibrium at a given temperature and pressure. The lines separating the three phases intersect at a single point, the triple point, which is the only combination of temperature and pressure at which all three phases can coexist in equilibrium. Water has an unusual phase diagram: its melting point decreases with increasing pressure because ice is less dense than liquid water. The phase diagram of carbon dioxide shows that liquid carbon dioxide cannot exist at atmospheric pressure. Consequently, solid carbon dioxide sublimes directly to a gas.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when the immune system reacts to substances in food as though they were harmful \u201cforeign invaders\"?","choices":["vomiting","food poisoning","food allergies","food antibodies"],"answer":"C","rationale":"Food allergies occur when the immune system reacts to substances in food as though they were harmful \u201cforeign invaders. \u201d Foods that are most likely to cause allergies are pictured in Figure below . Symptoms of food allergies often include vomiting and diarrhea.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Recycling items actually takes more energy than what other conservation methods that start with \"r\"?","choices":["revision and remembrance","reducing and regurgitating","reducing and reusing","reusing and reordering"],"answer":"C","rationale":"We haven\u2019t done as well with the first two \u201cR\u201ds \u2014 reducing and reusing. But they aren\u2019t always as easy as recycling. Recycling is better than making things from brand new materials. But it still takes some resources to turn recycled items into new ones. It takes no resources at all to reuse items or not buy them in the first place.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What science studies chemical processes that are found in living things?","choices":["physiology","psysiology","marine biology","biochemistry"],"answer":"D","rationale":"Biochemistry is the study of chemical processes in living systems. In this chapter, we will explore some of the basic chemical components of biological systems and develop an understanding of the roles played by each major type of biomolecule.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nonmetals typically lack what capability, because they hold onto their electrons?","choices":["conducting electricity","mental capacity","repelling electricity","magnetic attraction"],"answer":"A","rationale":"Like most other nonmetals, fluorine cannot conduct electricity, and its electrons explain this as well. An electric current is a flow of electrons. Elements that readily give up electrons (the metals) can carry electric current because their electrons can flow freely. Elements that gain electrons instead of giving them up cannot carry electric current. They hold onto their electrons so they cannot flow.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process called in which populations of organisms change over time?","choices":["generation","emergence","mutation","evolution"],"answer":"D","rationale":"Evolution is the process by which populations of organisms change over time. It is a process that began on this planet well over 3.5 billion years ago and continues to this day, as populations of organisms continue to change.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An environment reaches its carrying capacity when the number of individual births in it equal the number of what else?","choices":["deaths","infections","insects","homes"],"answer":"A","rationale":"The carrying capacity of an environment is reached when the number of births equal the number of deaths.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Pulmonary and systemic circulation loops are part of what organ system?","choices":["circulatory","lymphatic","cardiovascular","nervous"],"answer":"C","rationale":"Compare and contrast the pulmonary and systemic circulation loops of the cardiovascular system.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are materials that cannot conduct thermal energy efficiently known as?","choices":["convection insulators","physical insulators","thermal insulators","atmospheric insulators"],"answer":"C","rationale":"Materials that are poor conductors of thermal energy are called thermal insulators. Gases such as air and materials such as plastic and wood are thermal insulators.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The temporomandibular joint (tmj) is the joint that allows for opening (mandibular depression) and closing (mandibular elevation) of this?","choices":["ears","eyes","nose","mouth"],"answer":"D","rationale":"Temporomandibular Joint The temporomandibular joint (TMJ) is the joint that allows for opening (mandibular depression) and closing (mandibular elevation) of the mouth, as well as side-to-side and protraction\/retraction motions of the lower jaw. This joint involves the articulation between the mandibular fossa and articular tubercle of the temporal bone, with the condyle (head) of the mandible. Located between these bony structures, filling the gap between the skull and mandible, is a flexible articular disc (Figure 9.15). This disc serves to smooth the movements between the temporal bone and mandibular condyle. Movement at the TMJ during opening and closing of the mouth involves both gliding and hinge motions of the mandible. With the mouth closed, the mandibular condyle and articular disc are located within the mandibular fossa of the temporal bone. During opening of the mouth, the mandible hinges downward and at the same time is pulled anteriorly, causing both the condyle and the articular disc to glide forward from the mandibular fossa onto the downward projecting articular tubercle. The net result is a forward and downward motion of the condyle and mandibular depression. The temporomandibular joint is supported by an extrinsic ligament that anchors the mandible to the skull. This ligament spans the distance between the base of the skull and the lingula on the medial side of the mandibular ramus. Dislocation of the TMJ may occur when opening the mouth too wide (such as when taking a large bite) or following a blow to the jaw, resulting in the mandibular condyle moving beyond (anterior to) the articular tubercle. In this case, the individual would not be able to close his or her mouth. Temporomandibular joint disorder is a painful condition that may arise due to arthritis, wearing of the articular cartilage covering the bony surfaces of the joint, muscle fatigue from overuse or grinding of the teeth, damage to the articular disc within the joint, or jaw injury. Temporomandibular joint disorders can also cause headache, difficulty chewing, or even the inability to move the jaw (lock jaw). Pharmacologic agents for pain or other therapies, including bite guards, are used as treatments.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What gas consisting of three oxygen atoms is found largely in the stratosphere?","choices":["greenhouse","carbon","smog","ozone"],"answer":"D","rationale":"Air also includes water vapor. The amount of water vapor varies from place to place. That\u2019s why water vapor isn\u2019t included in Figure above . It can make up as much as 4 percent of the air. Ozone is a molecule made of three oxygen atoms. Ozone collects in a layer in the stratosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Esters can be formed by heating carboxylic acids and alcohols in the presence of?","choices":["an oxygen catalyst","an acid catalyst","a nuclear catalyst","an carbon catalyst"],"answer":"B","rationale":"Esters can be formed by heating carboxylic acids and alcohols in the presence of an acid catalyst. This process is reversible, and the starting materials can be regenerated by reacting an ester with water in the presence of a weak base.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Glucose that remains in the filtrate of what organ is excreted?","choices":["liver","kidney","spleen","intestine"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of a plant helps it reproduce by being ejected from flowers and fruits?","choices":["roots","cells","seeds","berries"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Energy contents of foods are often expressed in what?","choices":["calories","nutrients","pulses","grams"],"answer":"A","rationale":"One area where the calorie is used is in nutrition. Energy contents of foods are often expressed in calories. However, the calorie unit used for foods is actually the kilocalorie (kcal). Most foods indicate this by spelling the word with a capital C\u2014Calorie. Figure 7.1 \"Calories on Food Labels\" shows one example. So be careful counting calories when you eat!.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called what?","choices":["microvilli","flagella","epithelial","digits"],"answer":"A","rationale":"The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus); ( Figure 4.10). Such cells are typically found lining the small intestine, the organ that absorbs nutrients from digested food. This is an excellent example of form following function. People with celiac disease have an immune response to gluten, which is a protein found in wheat, barley, and rye. The immune response damages microvilli, and thus, afflicted individuals cannot absorb nutrients. This leads to malnutrition, cramping, and diarrhea. Patients suffering from celiac disease must follow a gluten-free diet.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sweating and panting are methods mammals use for what purpose?","choices":["staying warm","sleeping","staying cool","staying alert"],"answer":"C","rationale":"Mammals also have several ways to stay cool, including sweating or panting.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A closed loop through which a current can flow is called what?","choices":["cooling circuit","powered circuit","electric circuit","charged circuit"],"answer":"C","rationale":"A closed loop through which current can flow is called an electric circuit . In homes in the U. S. , most electric circuits have a voltage of 120 volts. The amount of current (amps) a circuit carries depends on the number and power of electrical devices connected to the circuit. Home circuits generally have a safe upper limit of about 20 or 30 amps.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Unsaturated hydrocarbons with at least one triple bond are known as?","choices":["aromatic hydrocarbons","benzenes","alkenes","alkynes"],"answer":"D","rationale":"Unsaturated hydrocarbons that contain at least one triple bond are called alkynes . The name of specific alkynes always end in \u2013 yne , with a prefix for the number of carbon atoms. Figure below shows the smallest alkyne, called ethyne, which has just two carbon atoms. Ethyne is also called acetylene. It is burned in acetylene torches, like the one in Figure below . Acetylene produces so much heat when it burns that it can melt metal. Breaking all those bonds between carbon atoms releases a lot of energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two types of organism make up a lichen?","choices":["insects and bacteria","animals and viruses","snakes and bacteria","fungus and bacteria"],"answer":"D","rationale":"Have you ever seen an organism called a lichen? Lichens are crusty, hard growths that you might find on trees, logs, walls, and rocks ( Figure below ). Although lichens may not be the prettiest organisms in nature, they are unique. A lichen is really two organisms, sometimes referred to as a composite organism, that live very closely together: a fungus and a bacterium or an alga. The cells from the alga or bacterium live inside the fungus. Besides providing a home, the fungus also provides nutrients. In turn, the bacterium or the alga provides energy to the fungus by performing photosynthesis, obtaining energy directly from the sun. A lichen is also an example of a mutualistic relationship. Because lichens can grow on rocks, these organisms are some of the earliest life forms in new ecosystems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The cell regulates most molecules that pass through what cell structure?","choices":["plasma","cell membrane","protective wall","ribosome"],"answer":"B","rationale":"The cell regulates most molecules that pass through the cell membrane. If a molecule is charged or very big, it won't make it through the cell membrane on its own. However, small, non-charged molecules like oxygen, carbon dioxide, and water, can pass through the cell membrane freely.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are groups of skeletal muscle fibers wrapped in?","choices":["collagen","neurons","tendons","connective tissue"],"answer":"D","rationale":"Each skeletal muscle consists of hundreds or even thousands of skeletal muscle fibers . The fibers are bundled together and wrapped in connective tissue, as shown Figure below . The connective tissue supports and protects the delicate muscle cells and allows them to withstand the forces of contraction. It also provides pathways for nerves and blood vessels to reach the muscles. Skeletal muscles work hard to move body parts. They need a rich blood supply to provide them with nutrients and oxygen and to carry away their wastes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Density is considered what type of property, because it does not depend on the amount of material present in the sample?","choices":["intensive property","exensive property","independent variable","experimental property"],"answer":"A","rationale":"Density is an intensive property, meaning that it does not depend on the amount of material present in the sample. Water has a density of 1.0 g\/mL. That density is the same whether you have a small glass of water or a swimming pool full of water. Density is a property that is constant for the particular identity of the matter being studied.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Prior to binding to a hormone, where are steroid hormone receptors located?","choices":["cytosol","reticulum","cortisol","hypothalamus"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which scale measures acids and bases and has 7 as a neutral value?","choices":["color","respiration","ph","rock"],"answer":"C","rationale":"The Concept of pH The relative acidity or alkalinity of a solution can be indicated by its pH. A solution\u2019s pH is the negative, base-10 logarithm of the hydrogen ion (H+) concentration of the solution. As an example, a pH 4 solution has an H+ concentration that is ten times greater than that of a pH 5 solution. That is, a solution with a pH of 4 is ten times more acidic than a solution with a pH of 5. The concept of pH will begin to make more sense when you study the pH scale, like that shown in Figure 2.17. The scale consists of a series of increments ranging from 0 to 14. A solution with a pH of 7 is considered neutral\u2014neither acidic nor basic. Pure water has a pH of 7. The lower the number below 7, the more acidic the solution, or the greater the concentration of H+. The concentration of hydrogen ions at each pH value is 10 times different than the next pH. For instance, a pH value of 4 corresponds to a proton concentration of 10\u20134 M, or 0.0001M, while a pH value of 5 corresponds to a proton concentration of 10\u20135 M, or 0.00001M. The higher the number above 7, the more basic (alkaline) the solution, or the lower the concentration of H+. Human urine, for example, is ten times more acidic than pure water, and HCl is 10,000,000 times more acidic than water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we call people who are trained to make specific dietary recommendations to address particular issues relating to health?","choices":["pulmonologists","clinicians","geologists","dietitians"],"answer":"D","rationale":"Career Focus: Dietitian A dietitian is a nutrition expert who communicates food-related information to the general public. In doing so, dietitians promote the general well-being among the population and help individuals recover from nutritionally related illnesses. Our diet does not just supply us with energy. We also get vitamins, minerals, and even water from what we eat. Eating too much, too little, or not enough of the right foods can lead to a variety of problems. Dietitians are trained to make specific dietary recommendations to address particular issues relating to health. For example, a dietitian might work with a person to develop an overall diet that would help that person lose weight or control diabetes. Hospitals employ dietitians in planning menus for patients, and many dietitians work with community organizations to improve the eating habits of large groups of people.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An artery is a blood vessel that conducts blood away from the what?","choices":["lung","stomach","heart","brain"],"answer":"C","rationale":"Arteries An artery is a blood vessel that conducts blood away from the heart. All arteries have relatively thick walls that can withstand the high pressure of blood ejected from the heart. However, those close to the heart have the thickest walls, containing a high percentage of elastic fibers in all three of their tunics. This type of artery is known as an elastic artery (Figure 20.4). Vessels larger than 10 mm in diameter are typically elastic. Their abundant elastic fibers allow them to expand, as blood pumped from the ventricles passes through them, and then to recoil after the surge has passed. If artery walls were rigid and unable to expand and recoil, their resistance to blood flow would greatly increase and blood pressure would rise to even higher levels, which would in turn require the heart to pump harder to increase the volume of blood expelled by each pump (the stroke volume) and maintain adequate pressure and flow. Artery walls would have to become even thicker in response to this increased pressure. The elastic recoil of the vascular wall helps to maintain the pressure gradient that drives the blood through the arterial system. An elastic artery is also known as a conducting artery, because the large diameter of the lumen enables it to accept a large volume of blood from the heart and conduct it to smaller branches.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The small amount of energy input necessary for all chemical reactions to occur is called what?","choices":["decomposition energy","nuclear energy","activation energy","distinct energy"],"answer":"C","rationale":"Activation Energy There is another important concept that must be considered regarding endergonic and exergonic reactions. Even exergonic reactions require a small amount of energy input to get going before they can proceed with their energy-releasing steps. These reactions have a net release of energy, but still require some energy in the beginning. This small amount of energy input necessary for all chemical reactions to occur is called the activation energy (or free energy of activation) and is abbreviated EA (Figure 6.10). Why would an energy-releasing, negative \u2206G reaction actually require some energy to proceed? The reason lies in the steps that take place during a chemical reaction. During chemical reactions, certain chemical bonds are broken and new ones are formed. For example, when a glucose molecule is broken down, bonds between the carbon atoms of the molecule are broken. Since these are energy-storing bonds, they release energy when broken. However, to get them into a state that allows the bonds to break, the molecule must be somewhat contorted. A small energy input is required to achieve this contorted state. This contorted state is called the transition state, and it is a high-energy, unstable state. For this reason, reactant molecules don\u2019t last long in their transition state, but very quickly proceed to the next steps of the chemical reaction. Free energy diagrams illustrate the energy profiles for a given reaction. Whether the reaction is exergonic or endergonic determines whether the products in the diagram will exist at a lower or higher energy state than both the reactants and the products. However, regardless of this measure, the transition state of the reaction exists at a higher energy state than the reactants, and thus, EA is always positive.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What linear polymer of glucose units is found in plants and serves a structural purpose?","choices":["carbonate","sucrose","cellulose","frucose"],"answer":"C","rationale":"Cellulose is a structural polymer of glucose units found in plants. It is a linear polymer with the glucose units linked through \u03b2-1,4-glycosidic bonds.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When the temperature of water is increased after being used in cooling, it is this form of pollution?","choices":["air","atmospheric","thermal","cosmic"],"answer":"C","rationale":"Thermal pollution is pollution that raises the temperature of water. This is caused by power plants and factories that use the water to cool their machines. The plants pump cold water from a lake or coastal area through giant cooling towers, like those in Figure below . As it flows through the towers, the cold water absorbs heat. This warmed water is returned to the lake or sea. Thermal pollution can kill fish and other water life. It's not just the warm temperature that kills them. Warm water can\u2019t hold as much oxygen as cool water. If the water gets too warm, there may not be enough oxygen for living things.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which biological system is responsible for getting rid of chemical waste and water?","choices":["endocrine system","digestive system","mucous system","urinary system"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of the body protects the brain?","choices":["lungs","feet","cranium (skull)","arms"],"answer":"C","rationale":"The cranium (skull) to protect the brain. The brain is attached to the spinal cord.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ammonium nitrate and ammonium sulfate are used in fertilizers as a source of what?","choices":["biofuel","nitrogen","oxygen","bacteria"],"answer":"B","rationale":"Ammonium nitrate and ammonium sulfate are used in fertilizers as a source of nitrogen. The ammonium cation is tetrahedral. Refer to Section 2.1 \"Chemical Compounds\" to draw the structure of the ammonium ion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of light bulb has a tungsten filament?","choices":["translucent","fluorescent","incandescent","sodium"],"answer":"C","rationale":"An incandescent light bulb like the one pictured in the Figure below produces visible light by incandescence. Incandescence occurs when something gets so hot that it glows. An incandescent light bulb contains a thin wire filament made of tungsten. When electric current passes through the filament, it gets extremely hot and emits light.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for the circle that runs north to south and passes through greenwich, england?","choices":["time zone","prime meridian","odd meridian","equator"],"answer":"B","rationale":"Lines of longitude are circles that go around Earth from pole to pole, like the sections of an orange. Longitude is also measured in degrees, which are subdivided into minutes and seconds. Lines of longitude start at the Prime Meridian, which is 0\u00b0. The Prime Meridian is a circle that runs north to south and passes through Greenwich, England. Longitude tells you how far you are east or west from the Prime Meridian ( Figure below ). On the opposite side of the planet from the Prime Meridian is the International Date Line. It is at 180\u00b0. This is the place where a new day first arrives.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What map coordinates correspond to similar climate zones and life zones?","choices":["equator and poles","latitude and longitude","altitude and latitude","the poles"],"answer":"C","rationale":"Altitude and latitude produce similar climate zones and life zones.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In myasthenia gravis, antibodies bind to and block certain receptors on muscle cells, preventing what?","choices":["muscle buildup","muscle diffusion","muscle layer","muscle contraction"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What helps cells reduce their reaction to excessive hormone levels?","choices":["apoptosis","adhesion","downregulation","evaporation"],"answer":"C","rationale":"Factors Affecting Target Cell Response You will recall that target cells must have receptors specific to a given hormone if that hormone is to trigger a response. But several other factors influence the target cell response. For example, the presence of a significant level of a hormone circulating in the bloodstream can cause its target cells to decrease their number of receptors for that hormone. This process is called downregulation, and it allows cells to become less reactive to the excessive hormone levels. When the level of a hormone is chronically reduced, target cells engage in upregulation to increase their number of receptors. This process allows cells to be more sensitive to the hormone that is present. Cells can also alter the sensitivity of the receptors themselves to various hormones. Two or more hormones can interact to affect the response of cells in a variety of ways. The three most common types of interaction are as follows: \u2022 The permissive effect, in which the presence of one hormone enables another hormone to act. For example, thyroid hormones have complex permissive relationships with certain reproductive hormones. A dietary deficiency of iodine, a component of thyroid hormones, can therefore affect reproductive system development and functioning. \u2022 The synergistic effect, in which two hormones with similar effects produce an amplified response. In some cases, two hormones are required for an adequate response. For example, two different reproductive hormones\u2014FSH from the pituitary gland and estrogens from the ovaries\u2014are required for the maturation of female ova (egg cells). \u2022 The antagonistic effect, in which two hormones have opposing effects. A familiar example is the effect of two pancreatic hormones, insulin and glucagon. Insulin increases the liver\u2019s storage of glucose as glycogen, decreasing blood glucose, whereas glucagon stimulates the breakdown of glycogen stores, increasing blood glucose.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Smog is an example of the formation of what kind of pollutant, which occurs when primary pollutants undergo chemical reactions after they are released?","choices":["combined pollutant","primary pollutant","secondary pollutant","tertiary pollutant"],"answer":"C","rationale":"Primary pollutants enter the air directly. They include carbon, nitrogen, and sulfur oxides. Toxic heavy metals, VOCs, and particulates are also primary pollutants. Secondary pollutants form when primary pollutants undergo chemical reactions after they are released. Many occur as part of photochemical smog. The main component of smog is ozone.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when a sperm and an egg fuse?","choices":["infection","pollination","migration","fertilization"],"answer":"D","rationale":"Many animals have a relatively simple life cycle. A general animal life cycle is shown in Figure below . Most animals spend the majority of their life as diploid organisms. Just about all animals reproduce sexually. Diploid adults undergo meiosis to produce haploid sperm or eggs. Fertilization occurs when a sperm and an egg fuse. The diploid zygote that forms develops into an embryo. The embryo eventually develops into an adult, often going through one or more larval stages on the way. A larva (larvae, plural) is a distinct juvenile form that many animals go through before becoming an adult. The larval form may be very different from the adult form. For example, a caterpillar is the larval form of an insect that becomes a butterfly as an adult.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How many bases does dna have in total?","choices":["four","twelve","three","six"],"answer":"A","rationale":"Every DNA and RNA polymer consists of multiple nucleotides strung together into extremely long chains. The only variation in each nucleotide is the identity of the nitrogenous base. The figure above shows one example of a nitrogenous base, called adenine. There are only five different nitrogenous bases found in all nucleic acids. The four bases of DNA are adenine, thymine, cytosine, and guanine, abbreviated A, T, C, and G respectively. In RNA, the base thymine is not found and is instead replaced by a different base called uracil, abbreviated U. The other three bases are present in both DNA and RNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Compound machines tend to have a greater mechanical advantage than what other machines?","choices":["magnets","digital machines","simple machines","levers"],"answer":"C","rationale":"The mechanical advantage of a machine is the factor by which it changes the force applied to the machine. Many machines increase the force applied to them, and this is how they make work easier. Compound machines tend to have a greater mechanical advantage than simple machines. That\u2019s because the mechanical advantage of a compound machine equals the product of the mechanical advantages of all its component simple machines. The greater the number of simple machines it contains, the greater its mechanical advantage tends to be.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Name the missing type of light: ultraviolet, infrared, ___________.","choices":["vertical","predictable","distinct","visible"],"answer":"D","rationale":"Between these two extremes are waves that are commonly called light. Light includes infrared light, visible light, and ultraviolet light. The wavelengths, frequencies, and energy levels of light fall in between those of radio waves on the left and X rays and gamma rays on the right.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When a binary acid only has one acidic hydrogen it is known as what?","choices":["xerophyte","triprotic","spirogyra","monoprotic"],"answer":"D","rationale":"Most of the binary acids listed here are monoprotic, because they have only one acidic hydrogen. Hydrosulfuric acid, on the other hand is diprotic. Its hydrogen ions are transferred to two water molecules in two subsequent reactions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Seedless nonvascular plants are small. the dominant stage of the life cycle is the gametophyte. without a vascular system and roots, they absorb water and nutrients through all of their exposed surfaces. there are three main groups: the liverworts, the hornworts, and these?","choices":["mildew","mosses","algae","lichens"],"answer":"B","rationale":"14.2 Seedless Plants Seedless nonvascular plants are small. The dominant stage of the life cycle is the gametophyte. Without a vascular system and roots, they absorb water and nutrients through all of their exposed surfaces. There are three main groups: the liverworts, the hornworts, and the mosses. They are collectively known as bryophytes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a protein containing four subunits that transports oxygen throughout the body?","choices":["insulin","keratin","hemoglobin","collagen"],"answer":"C","rationale":"Hemoglobin is a protein containing four subunits that transports oxygen throughout the body.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Molecules that are in continuous motion, travelling in straight lines and changing comprise what state of matter?","choices":["plasma","liquids","solids","gases"],"answer":"D","rationale":"Gases are composed of molecules that are in continuous motion, travelling in straight lines and changing.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The recombination frequency is the percentage of recombinant flies in the total pool of what?","choices":["immigrants","samples","offspring","species"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nuclear fusion is a reaction in which two nuclei are combined to form a larger nucleus. it releases energy when light nuclei are fused to form medium-mass nuclei. \u2022 fusion is the source of energy in what?","choices":["orbits","galaxies","stars","Space"],"answer":"C","rationale":"32.5 Fusion \u2022 Nuclear fusion is a reaction in which two nuclei are combined to form a larger nucleus. It releases energy when light nuclei are fused to form medium-mass nuclei. \u2022 Fusion is the source of energy in stars, with the proton-proton cycle, 1.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are polymers of amino acids called?","choices":["polypeptides","monopeptides","ribosomes","polysaccharides"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Currently, the only known stable systems undergoing fusion are what?","choices":["plant cells","black holes","interiors of stars","gas planets"],"answer":"C","rationale":"Fusion occurs in nature: The sun and other stars use fusion as their ultimate energy source. Fusion is also the basis of very destructive weapons that have been developed by several countries around the world. However, one current goal is to develop a source ofcontrolled fusion for use as an energy source. The practical problem is that to perform fusion, extremely high pressures and temperatures are necessary. Currently, the only known stable systems undergoing fusion are the interiors of stars. The conditions necessary for fusion can be created using an atomic bomb, but the resulting fusion is uncontrollable (and the basis for another type of bomb, a hydrogen bomb). Currently, researchers are looking for safe, controlled ways for producing useful energy using fusion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Displacement is the separation between a beginning position and what other place?","choices":["final position","current position","made position","first position"],"answer":"A","rationale":"The separation between original and final position is called displacement.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cellular respiration that proceeds in the absence of oxygen is called what?","choices":["exasperation","perspiration","anaerobic respiration","aerobic respiration"],"answer":"C","rationale":"Cellular respiration that proceeds in the absence of oxygen is anaerobic respiration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is made in the liver and excreted in urine?","choices":["plasma","urea","blood","feces"],"answer":"B","rationale":"Nitrogenous Waste in Terrestrial Animals: The Urea Cycle The urea cycle is the primary mechanism by which mammals convert ammonia to urea. Urea is made in the liver and excreted in urine. The overall chemical reaction by which ammonia is converted to urea is 2 NH3 (ammonia) + CO2 + 3 ATP + H2O \u2192 H2N-CO-NH2 (urea) + 2 ADP + 4 Pi + AMP. The urea cycle utilizes five intermediate steps, catalyzed by five different enzymes, to convert ammonia to urea, as shown in Figure 41.12. The amino acid L-ornithine gets converted into different intermediates before being regenerated at the end of the urea cycle. Hence, the urea cycle is also referred to as the ornithine cycle. The enzyme ornithine transcarbamylase catalyzes a key step in the urea cycle and its deficiency can lead to accumulation of toxic levels of ammonia in the body. The first two reactions occur in the mitochondria and the last three reactions occur in the cytosol. Urea concentration in the blood, called blood urea nitrogen or BUN, is used as an indicator of kidney function.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Name two differences between a larval staged frog and an adult frog.","choices":["tadpoles have legs and gills","tadpoles lack eyes and fins","tadpoles lack legs and have gills","tadpoles lack legs and gills"],"answer":"C","rationale":"Most amphibians go through a larval stage that is different from the adult form. In frogs, for example, the early larval stage resembles a fish, as you can see in Figure below . Frogs at this stage of development are called tadpoles. Tadpoles live in the water. They lack legs and have a long tail that helps them swim. They also have gills, which absorb oxygen from the water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of energy can both cause cancer and help in detecting and treating it?","choices":["wind","electricity","heat","radiation"],"answer":"D","rationale":"Harmless background radiation comes from radioactive elements in rocks and from cosmic rays. Other sources of radiation, such as radon, are harmful. They may cause illness in living things and damage materials such as metals. Radiation has several uses, including detecting and treating cancer.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What was probably the earliest way of making atp from glucose?","choices":["glycolysis","photosynthesis","amniocentesis","fermentation"],"answer":"A","rationale":"Life first evolved in the absence of oxygen, and glycolysis does not require oxygen. Therefore, glycolysis was probably the earliest way of making ATP from glucose.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process in which a substance naturally moves from an area of higher to lower concentration called?","choices":["convection","osmosis","activation","diffusion"],"answer":"D","rationale":"Why does passive transport require no energy? A substance naturally moves from an area of higher to lower concentration. This is known as moving down the concentration gradient. The process is called diffusion . It's a little like a ball rolling down a hill. The ball naturally rolls from a higher to lower position without any added energy. You can see diffusion if you place a few drops of food coloring in a pan of water. Even without shaking or stirring, the food coloring gradually spreads throughout the water in the pan. Some substances can also diffuse through a cell membrane. This can occur in two ways: simple diffusion or facilitated diffusion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the internal ph of most living cells?","choices":["close to 6","close to 5","close to 9","close to 7"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What law states whenever one body exerts a force on a second body, the first body experiences a force that is equal in magnitude and opposite in direction to the force that the first body exerts?","choices":["law of gravity","equilibrium in forces","symmetry in forces","law of inertia"],"answer":"C","rationale":"4.4 Newton\u2019s Third Law of Motion: Symmetry in Forces \u2022 Newton\u2019s third law of motion represents a basic symmetry in nature. It states: Whenever one body exerts a force on a second body, the first body experiences a force that is equal in magnitude and opposite in direction to the force that the first body exerts. \u2022 A thrust is a reaction force that pushes a body forward in response to a backward force. Rockets, airplanes, and cars are pushed forward by a thrust reaction force.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does the bicoid protein activate?","choices":["spontaneous mutation","several gap genes","amino acid production","enzyme respiration"],"answer":"B","rationale":"The bicoid protein activates a number of gap genes. Bicoid encodes a homeodomain-containing transcription factor, and is expressed in a gradient within the embryo. Bicoid positions gap and pair rule gene expression along the anterior-posterior axis of the developing Drosophila embryo.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How do roundworms reproduce?","choices":["biologically","sporadically","asexually","sexually"],"answer":"D","rationale":"Roundworms reproduce sexually. Sperm and eggs are produced by separate male and female adults. Fertilization takes place inside the female organism. Females lay huge numbers of eggs, sometimes as many as 100,000 per day! The eggs hatch into larvae, which develop into adults. Then the cycle repeats.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Intraspecific competition occurs between members of the same what?","choices":["phylum","species","specimens","genus"],"answer":"B","rationale":"Competition is a relationship between organisms that strive for the same resources in the same place. Intraspecific competition occurs between members of the same species. It improves the species\u2019 adaptations. Interspecific competition occurs between members of different species. It may lead to one species going extinct or both becoming more specialized.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the long-time average of weather?","choices":["climate","scale","landscape","evolution"],"answer":"A","rationale":"Climate is the long-term average of weather.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most common form of ocean life?","choices":["protazoa","zooplankton","phytoplankton","plankton"],"answer":"D","rationale":"When you think of life in the ocean, do you think of fish? Actually, fish are not the most common life forms in the ocean. Plankton are the most common. Plankton make up one of three major groups of marine life. The other two groups are nekton and benthos ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the chart that makes it easy to find the possible genotypes in offspring of two parents?","choices":["Isotropic Square","brindle square","malecela square","punnett square"],"answer":"D","rationale":"A Punnett square is a chart that makes it easy to find the possible genotypes in offspring of two parents. Figure below shows a Punnett square for the two parent pea plants. The gametes produced by the male parent are at the top of the chart. The gametes produced by the female parent are along the left side of the chart. The different possible combinations of alleles in their offspring can be found by filling in the cells of the chart.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term is used to describe the process of finding the location of genes on each chromosome?","choices":["genome mapping","produce mapping","organism mapping","DNA replication"],"answer":"A","rationale":"Mapping Genomes Genome mapping is the process of finding the location of genes on each chromosome. The maps that are created are comparable to the maps that we use to navigate streets. A genetic map is an illustration that lists genes and their location on a chromosome. Genetic maps provide the big picture (similar to a map of interstate highways) and use genetic markers (similar to landmarks). A genetic marker is a gene or sequence on a chromosome that shows genetic linkage with a trait of interest. The genetic marker tends to be inherited with the gene of interest, and one measure of distance between them is the recombination frequency during meiosis. Early geneticists called this linkage analysis. Physical maps get into the intimate details of smaller regions of the chromosomes (similar to a detailed road map) (Figure 10.11). A physical map is a representation of the physical distance, in nucleotides, between genes or genetic markers. Both genetic linkage maps and physical maps are required to build a complete picture of the genome. Having a complete map of the genome makes it easier for researchers to study individual genes. Human genome maps help researchers in their efforts to identify human disease-causing genes related to illnesses such as cancer, heart disease, and cystic fibrosis, to name a few. In addition, genome mapping can be used to help identify organisms with beneficial traits, such as microbes with the ability to clean up pollutants or even prevent pollution. Research involving plant genome mapping may lead to methods that produce higher crop yields or to the development of plants that adapt better to climate change.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a threat against civilized people called?","choices":["bioterrorism","bombing","pandemic","disaster"],"answer":"A","rationale":"Bioterrorism is a threat against civilized people worldwide. To be prepared, all levels of government have developed and conducted terrorism drills. These include protecting responders from harmful biological substances.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the most common forms of lasers today made of?","choices":["spirogyra","light","prisms","silcon"],"answer":"D","rationale":"Lasers are constructed from many types of lasing materials, including gases, liquids, solids, and semiconductors. But all lasers are based on the existence of a metastable state or a phosphorescent material. Some lasers produce continuous output; others are pulsed in bursts as brief as 10 \u221214 s . Some laser outputs are fantastically powerful\u2014some greater than 10 12 W \u2014but the \u22123 more common, everyday lasers produce something on the order of 10 W . The helium-neon laser that produces a familiar red light is very common. Figure 30.39 shows the energy levels of helium and neon, a pair of noble gases that work well together. An electrical discharge is passed through a helium-neon gas mixture in which the number of atoms of helium is ten times that of neon. The first excited state of helium is metastable and, thus, stores energy. This energy is easily transferred by collision to neon atoms, because they have an excited state at nearly the same energy as that in helium. That state in neon is also metastable, and this is the one that produces the laser output. (The most likely transition is to the nearby state, producing 1.96 eV photons, which have a wavelength of 633 nm and appear red. ) A population inversion can be produced in neon, because there are so many more helium atoms and these put energy into the neon. Helium-neon lasers often have continuous output, because the population inversion can be maintained even while lasing occurs. Probably the most common lasers in use today, including the common laser pointer, are semiconductor or diode lasers, made of silicon. Here, energy is pumped into the material by passing a current in the device to excite the electrons. Special coatings on the ends and fine cleavings of the semiconductor material allow light to bounce back and forth and a tiny fraction to emerge as laser light. Diode lasers can usually run continually and produce outputs in the milliwatt range.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A phospholipid bilayer is made up of two layers of phospholipids, in which hydrophobic fatty acids are in the middle of the what?","choices":["cells membrane","cell wall","skin","plasma membrane"],"answer":"D","rationale":"A phospholipid is made up of a polar, phosphorus-containing head, and two long fatty acid (hydrocarbon), non-polar \"tails. \" That is, the head of the molecule is hydrophilic (water-loving), and the tail is hydrophobic (water-fearing). Cytosol and extracellular fluid - the insides and outsides of the cell - are made up of mostly water. In this watery environment, the water loving heads point out towards the water, and the water fearing tails point inwards, and push the water out. The resulting double layer is called a phospholipid bilayer. A phospholipid bilayer is made up of two layers of phospholipids, in which hydrophobic fatty acids are in the middle of the plasma membrane, and the hydrophilic heads are on the outside. An example of a simple phospholipid bilayer is illustrated in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"The transfer of energy by electromagnetic waves is called what?","choices":["electromagnetic radiation","particulate radiation","magnetic radiation","mechanical radiation"],"answer":"A","rationale":"Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electromagnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation . Electromagnetic waves can transfer energy through matter or across empty space. For an excellent video introduction to electromagnetic waves, go to this URL: http:\/\/www. youtube. com\/watch?v=cfXzwh3KadE.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The noble gases are unreactive because of their?","choices":["carbon content","electron configurations","proton configurations","cell configurations"],"answer":"B","rationale":"The noble gases are unreactive because of their electron configurations. The noble gas neon has the electron configuration of 1 s 2 2 s 2 2 p 6 . It has a full outer shell and cannot incorporate any more electrons into the valence shell. The other noble gases have the same outer shell electron configuration even though they have different numbers of inner-shell electrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some birds, such as gulls and terns and other waterfowl have what type of feet used for swimming or floating?","choices":["bipedal","quad toed","webbed","lobed"],"answer":"C","rationale":"Bird feet can also vary greatly among different birds. Some birds, such as gulls and terns and other waterfowl, have webbed feet used for swimming or floating ( Figure below ). Other birds, such as herons, gallinules, and rails, have four long spreading toes, which are adapted for walking delicately in the wetlands ( Figure below ). You can predict how the beaks and feet of birds will look depending on where they live and what type of food they eat. Flightless birds also have long legs that are adapted for running. Flightless birds include the ostrich and kiwi.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Bones are considered organs because they contain what, specifically?","choices":["calcium","blood","tissue","DNA"],"answer":"C","rationale":"Bone Tissue Bones are considered organs because they contain various types of tissue, such as blood, connective tissue, nerves, and bone tissue. Osteocytes, the living cells of bone tissue, form the mineral matrix of bones. There are two types of bone tissue: compact and spongy. Compact Bone Tissue Compact bone (or cortical bone) forms the hard external layer of all bones and surrounds the medullary cavity, or bone marrow. It provides protection and strength to bones. Compact bone tissue consists of units called osteons or Haversian systems. Osteons are cylindrical structures that contain a mineral matrix and living osteocytes connected by canaliculi, which transport blood. They are aligned parallel to the long axis of the bone. Each osteon consists of lamellae, which are layers of compact matrix that surround a central canal called the Haversian canal. The Haversian canal (osteonic canal) contains the bone\u2019s blood vessels and nerve fibers (Figure 38.19). Osteons in compact bone tissue are aligned in the same direction along lines of stress and help the bone resist bending or fracturing. Therefore, compact bone tissue is prominent in areas of bone at which stresses are applied in only a few directions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Plants take in carbon dioxide and give off what?","choices":["methane","nitrogen","chlorophyll","oxygen"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"For a scientific theory to be valid, in what way should it be verified?","choices":["optimally","directly","experimentally","systematically"],"answer":"C","rationale":"For a scientific theory to be valid, it must be verified experimentally. Many parts of the string theory are currently untestable due to the large amount of energy that would be needed to carry out the necessary experiments as well as the high cost of conducting these experiments. Therefore string theory may not be tested in the foreseeable future. Some scientists have even questioned whether it deserves to be called a scientific theory because it is not falsifiable.","split":"validation","source_dataset":"sciq","subject":null},{"question":"For plants, the amount of water, sunlight, nutrients, and space to grow are the important resources, whereas in animals, important resources include food, water, shelter, nesting space, and this?","choices":["mates","eggs","entertainment","pairs"],"answer":"A","rationale":"Role of Intraspecific Competition The logistic model assumes that every individual within a population will have equal access to resources and, thus, an equal chance for survival. For plants, the amount of water, sunlight, nutrients, and space to grow are the important resources, whereas in animals, important resources include food, water, shelter, nesting space, and mates. In the real world, phenotypic variation among individuals within a population means that some individuals will be better adapted to their environment than others. The resulting competition for resources among population members of the same species is termed intraspecific competition. Intraspecific competition may not affect populations that are well below their carrying capacity, as resources are plentiful and all individuals can obtain what they need. However, as population size increases, this competition intensifies. In addition, the accumulation of waste products can reduce carrying capacity in an environment. Examples of Logistic Growth Yeast, a microscopic fungus used to make bread and alcoholic beverages, exhibits the classical S-shaped curve when grown in a test tube (Figure 19.6a). Its growth levels off as the population depletes the nutrients that are necessary for its growth. In the real world, however, there are variations to this idealized curve. Examples in wild populations include sheep and harbor seals (Figure 19.6b). In both examples, the population size exceeds the carrying capacity for short periods of time and then falls below the carrying capacity afterwards. This fluctuation in population size continues to occur as the population oscillates around its carrying capacity. Still, even with this oscillation, the logistic model is confirmed.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which is the main organ of the respiratory system?","choices":["the mouth","the stomach","the lungs","the liver"],"answer":"C","rationale":"When you think of the processes of breathing, the lungs probably come to mind. The lungs are the main organ of the respiratory system. However, many other organs are also needed for the process of respiration to take place.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why is runoff from artificial fertilizer harmful to the chesapeake bay ecosystem?","choices":["starts combustion","causes erosion","leaks food","causes pollution"],"answer":"D","rationale":"The Chesapeake Bay has long been valued as one of the most scenic areas on Earth; it is now in distress and is recognized as a declining ecosystem. In the 1970s, the Chesapeake Bay was one of the first ecosystems to have identified dead zones, which continue to kill many fish and bottom-dwelling species, such as clams, oysters, and worms. Several species have declined in the Chesapeake Bay due to surface water runoff containing excess nutrients from artificial fertilizer used on land. The source of the fertilizers (with high nitrogen and phosphate content) is not limited to agricultural practices. There are many nearby urban areas and more than 150 rivers and streams empty into the bay that are carrying fertilizer runoff from lawns and gardens. Thus, the decline of the Chesapeake Bay is a complex issue and requires the cooperation of industry, agriculture, and everyday homeowners. Of particular interest to conservationists is the oyster population; it is estimated that more than 200,000 acres of oyster reefs existed in the bay in the 1700s, but that number has now declined to only 36,000 acres. Oyster harvesting was once a major industry for Chesapeake Bay, but it declined 88 percent between 1982 and 2007. This decline was due not only to fertilizer runoff and dead zones but also to overharvesting. Oysters require a certain minimum population density because they must be in close proximity to reproduce. Human activity has altered the oyster population and locations, greatly disrupting the ecosystem. The restoration of the oyster population in the Chesapeake Bay has been ongoing for several years with mixed success. Not only do many people find oysters good to eat, but they also clean up the bay. Oysters are filter feeders, and as they eat, they clean the water around them. In the 1700s, it was estimated that it took only a few days for the oyster population to filter the entire volume of the bay. Today, with changed water conditions, it is estimated that the present population would take nearly a year to do the same job. Restoration efforts have been ongoing for several years by non-profit organizations, such as the Chesapeake Bay Foundation. The restoration goal is to find a way to increase population density so the oysters can reproduce more efficiently. Many disease-resistant varieties (developed at the Virginia Institute of Marine Science for the College of William and Mary) are now available and have been used in the construction of experimental oyster reefs. Efforts to clean and restore the bay by Virginia and Delaware have been hampered because much of the pollution entering the bay comes from other states, which stresses the need for inter-state cooperation to gain successful restoration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What system do trees need to transport nutrients?","choices":["vascular","circulatory","passive transport membrane","photosynthetic system"],"answer":"A","rationale":"The trees tower in the sky, while the mosses carpet the forest floor. Mosses, like the first plants, are restricted to life near the ground because they lack vascular system. Only with a vascular system can these trees transport sugars, nutrients, and water up and down their tall trunks. The evolution of the vascular system was a big step in the evolutionary history of plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Food allergies, ulcers, and heartburn all affect what organ system?","choices":["digestive system","skeletal system","lymphatic system","nervous system"],"answer":"A","rationale":"Many diseases can affect the digestive system. Three of the most common diseases that affect the digestive system are food allergies, ulcers, and heartburn. Foodborne illnesses and food intolerance are also serious issues associated with the digestive system.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Like ammonia, hydrazine is both a br\u00f8nsted base and which other base?","choices":["lewis base","dynamic base","unit base","floyd base"],"answer":"A","rationale":"Like ammonia, hydrazine is both a Br\u00f8nsted base and a Lewis base, although it is weaker than ammonia. It reacts with strong acids and forms two series of salts that contain the N 2 H 5 + and N 2 H 6 2+ ions, respectively. Some rockets use hydrazine as a fuel.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the layman's term for a state in which external stimuli are received but not consciously perceived?","choices":["sleep","dreaming","immunity","homeostasis"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the tiny, negatively charged particles in an atom that move around the positive nucleus at the center?","choices":["protons","electrons","quarks","neutrons"],"answer":"B","rationale":"Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the steps of a staircase. You can stand on one step or another but not in between the steps. The same goes for electrons. They can occupy one energy level or another but not the space between energy levels.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Enzymes, antibodies, and muscle fiber are all types of what?","choices":["carbohydrates","proteins","acids","lipids"],"answer":"B","rationale":"Many important molecules in your body are proteins. Examples include enzymes, antibodies, and muscle fiber. Enzymes are a type of protein that speed up chemical reactions. They are known as \"biological catalysts. \" For example, your stomach would not be able to break down food if it did not have special enzymes to speed up the rate of digestion. Antibodies that protect you against disease are proteins. Muscle fiber is mostly protein ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are formed by the loss of one or two electrons from an element?","choices":["cations","isotopes","ions","amines"],"answer":"A","rationale":"Cations are formed by the loss of one or two electrons from an element.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Betelgeuse is an example of what \"colorful\" stage in the life of very massive stars?","choices":["blue star","red supergiant","blue supergiant","white supergiant"],"answer":"B","rationale":"A more massive star ends its life in a more dramatic way. Very massive stars become red supergiants, like Betelgeuse.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What single word can be defined as the ability to cause change in matter and the ability to do work?","choices":["explosion","job","gas","energy"],"answer":"D","rationale":"The concept of energy was first introduced in the chapter \"States of Matter,\" where it is defined as the ability to cause change in matter. Energy can also be defined as the ability to do work. Work is done whenever a force is used to move matter. When work is done, energy is transferred from one object to another. For example, when the batter in Figure below uses energy to swing the bat, she transfers energy to the bat. The moving bat, in turn, transfers energy to the ball. Like work, energy is measured in the joule (J), or newton\u00b7meter (N\u00b7m).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Wearing clothes that trap air next to your body on a cold day helps you retain what type of energy?","choices":["caloric energy","thermal energy","alumal energy","adjacent energy"],"answer":"B","rationale":"One way to retain your own thermal energy on a cold day is to wear clothes that trap air. That\u2019s because air, like other gases, is a poor conductor of thermal energy. The particles of gases are relatively far apart, so they don\u2019t bump into each other or into other things as often as the more closely spaced particles of liquids or solids. Therefore, particles of gases have fewer opportunities to transfer thermal energy. Materials that are poor thermal conductors are called thermal insulators . Down-filled snowsuits, like those in the Figure below , are good thermal insulators because their feather filling traps a lot of air.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How many steps are involved in blood clotting?","choices":["five","two","six","three"],"answer":"D","rationale":"Figure 18.14 Hemostasis (a) An injury to a blood vessel initiates the process of hemostasis. Blood clotting involves three steps. First, vascular spasm constricts the flow of blood. Next, a platelet plug forms to temporarily seal small openings in the vessel. Coagulation then enables the repair of the vessel wall once the leakage of blood has stopped. (b) The synthesis of fibrin in blood clots involves either an intrinsic pathway or an extrinsic pathway, both of which lead to a common pathway. (credit a: Kevin MacKenzie).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of pressure is the amount of force that is exerted by gases in the air surrounding any given surface?","choices":["gravitational","vapor","fluid","atmospheric"],"answer":"D","rationale":"Pulmonary ventilation is dependent on three types of pressure: atmospheric, intra-alveolar, and interpleural. Atmospheric pressure is the amount of force that is exerted by gases in the air surrounding any given surface, such as the body. Atmospheric pressure can be expressed in terms of the unit atmosphere, abbreviated atm, or in millimeters of mercury (mm Hg). One atm is equal to 760 mm Hg, which is the atmospheric pressure at sea level. Typically, for respiration, other pressure values are discussed in relation to atmospheric pressure. Therefore, negative pressure is pressure lower than the atmospheric pressure, whereas positive pressure is pressure that it is greater than the atmospheric pressure. A pressure that is equal to the atmospheric pressure is expressed as zero. Intra-alveolar pressure is the pressure of the air within the alveoli, which changes during the different phases of breathing (Figure 22.16). Because the alveoli are connected to the atmosphere via the tubing of the airways (similar to the two- and one-liter containers in the example above), the interpulmonary pressure of the alveoli always equalizes with the atmospheric pressure.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What series of reactions is common to fermentation and cellular respiration?","choices":["metabolism","photosynthesis","spermatogenesis","glycolysis"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"In which ways may sponges reproduce?","choices":["internally and externally","sexually and vertically","sexually and asexually","meiosis and mitosis"],"answer":"C","rationale":"The sponge life cycle includes sexual reproduction. Sponges may also reproduce asexually.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do barnacles anchor to?","choices":["fossils","rocks","scales","eggs"],"answer":"B","rationale":"Mo Riza. Barnacles are adapted to the intertidal zone by anchoring to rocks . CC BY 2.0.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Organic compounds produced by what process provide the energy and building material for ecosystems?","choices":["cyclogenesis","nuclear fusion","glycolysis","photosynthesis"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"As you increase the temperature of a liquid what happens to the solubility of a solute?","choices":["viscosity increases","hydrophilic increases","solubility increases","turbidity increases"],"answer":"C","rationale":"Temperature affects the solubility of a solute. However, it affects the solubility of gases differently than the solubility of solids and liquids.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The relative sizes of the atoms show several trends with regard to what visual method of organization?","choices":["vibrations table","oscillations table","periodic table","chemistry table"],"answer":"C","rationale":"The relative sizes of the atoms show several trends with regard to the structure of the periodic table. Atoms become larger going down a column and smaller going across a period.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Toward the end of pregnancy, the synthesis of oxytocin receptors in what reproductive organ increases?","choices":["lungs","uterus","stomach","liver"],"answer":"B","rationale":"Oxytocin When fetal development is complete, the peptide-derived hormone oxytocin (tocia- = \u201cchildbirth\u201d) stimulates uterine contractions and dilation of the cervix. Throughout most of pregnancy, oxytocin hormone receptors are not expressed at high levels in the uterus. Toward the end of pregnancy, the synthesis of oxytocin receptors in the uterus increases, and the smooth.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If an animal eats large pieces of food it is known as a?","choices":["large consumer","bulk feeder","bulk producer","many feeder"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the two vibrating fields that electromagnetic waves consist of?","choices":["flammable and magnetic","magnetic and mechanical","electric and magnetic","radioactive and magnetic"],"answer":"C","rationale":"Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. They transfer energy through matter or across space. The transfer of energy by electromagnetic waves is called electromagnetic radiation.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process by which plants and animals increase in size?","choices":["birth","activity","growth","reproduction"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"How do endocrine hormones travel throughout the body?","choices":["in the blood","in the lymph","in mucus","in urea"],"answer":"A","rationale":"Endocrine hormones travel throughout the body in the blood. However, each endocrine hormone affects only certain cells, called target cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The post-anal tail is at the end of the organism opposite what?","choices":["legs","head","knees","fingers"],"answer":"B","rationale":"The post-anal tail is at the end of the organism opposite the head. It extends beyond the anus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the moles of solute divided by the kilograms of solvent?","choices":["molar weight","molar solvency","molality","kilocalorie"],"answer":"C","rationale":"A final way to express the concentration of a solution is by its molality. The molality ( m ) of a solution is the moles of solute divided by the kilograms of solvent. A solution that contains 1.0 mol of NaCl dissolved into 1.0 kg of water is a \u201cone-molal\u201d solution of sodium chloride. The symbol for molality is a lower-case m written in italics.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Active transport moves substances from an area of lower concentration to an area of?","choices":["the same concentration","higher concentration","low concentration","flat concentration"],"answer":"B","rationale":"Active transport requires energy because it moves substances from an area of lower to higher concentration. An example is the sodium-potassium pump. Another form of active transport is vesicle transport, which is needed for very large molecules.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How does the skin eliminates excess water and salts?","choices":["burn","sweat","itch","peel"],"answer":"B","rationale":"The skin eliminates excess water and salts in sweat.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Organophosphates typically interfere with nerve signal transmission by inhibiting the enzymes that degrade what?","choices":["prototype molecules","protein molecules","transmitter molecules","potassium molecules"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the horizontal distance between two waves, measured at a common point (crest to crest or trough to trough), called?","choices":["wavelength","linear","absorption","frequency"],"answer":"A","rationale":"Seismic waves are just one type of wave. Sound and light also travel in waves. Every wave has a high point called a crest and a low point called a trough . The height of a wave from the center line to its crest is its amplitude . The horizontal distance between waves from crest to crest (or trough to trough) is its wavelength ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Steroid hormones, such as cortisol and ecdysteroid, are lipids that contain four fused what?","choices":["oxide rings","acid rings","carbon rings","nitrogen rings"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The solubility of gases, liquids, and solids are affected by changes in what?","choices":["volume","friction","elevation","temperature"],"answer":"D","rationale":"The solubility of gases, liquids, and solids are affected by changes in temperature.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Only animals have muscle tissue and what other type of tissue?","choices":["cartilage","nervous","vascular tissue","nonvascular tissue"],"answer":"B","rationale":"23.29 Characteristics of an Animal \u2022 There is no one universally accepted definition of an animal. The following treatment follows your text, beginning on page 876. \u2022 Animals: \u2022 Are multicellular, heterotrophic eukaryotes . \u2022 Lack the distinctive cell walls of plants & fungi \u2022 Share unique characteristics . \u2022 Share certain reproductive characteristics . \u2022 Other commonly used definitions . Animals are multicellular heterotrophic eukaryotes \u2022 Unfortunately, none of these traits is exclusive to animals: \u2022 Plants, fungi, and some algae are multicellular. \u2022 Many bacteria, protists, and all fungi are heterotrophic. \u2022 Everything other than bacteria and archaea are eukaryotic. \u2022 Moreover, all three of these characteristics also apply to fungi. \u2022 However, there is a difference here between animals and fungi. Animals generally take in their food through ingestion, or eating and swallowing something. Fungi are absorptive heterotrophs; they secrete their digestive enzymes onto their food, and then absorb the resulting nutrients. Animals share unique characteristics \u2022 Only animals have muscle tissue and nervous tissue. \u2022 Only animals have collagen, a structural protein \u2022 Only animals have the following types of intercellular junctions: (See pages 135 - 139, Figure 7.15 in your text for more information on these junctions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of matter transmits light but scatters the light as it passes through?","choices":["a mirror","opaque matter","translucent matter","refractive matter"],"answer":"C","rationale":"Translucent matter is matter that transmits light but scatters the light as it passes through. Light passes through translucent objects but you cannot see clearly through them because the light is scattered in all directions. The frosted glass panes at the bottom of the window above are translucent.","split":"validation","source_dataset":"sciq","subject":null},{"question":"During an earthquake, the ground shakes as stored up energy is released from what?","choices":["rocks","the soil","fossils","grass"],"answer":"A","rationale":"During an earthquake, the ground shakes as stored up energy is released from rocks.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Tunnel vision involves the loss of what visual fields?","choices":["quickly-moving","distant","underwater","peripheral"],"answer":"D","rationale":"A unique clinical presentation that relates to this anatomic arrangement is the loss of lateral peripheral vision, known as bilateral hemianopia. This is different from \u201ctunnel vision\u201d because the superior and inferior peripheral fields are not lost. Visual field deficits can be disturbing for a patient, but in this case, the cause is not within the visual system itself. A growth of the pituitary gland presses against the optic chiasm and interferes with signal transmission. However, the axons projecting to the same side of the brain are unaffected. Therefore, the patient loses the outermost areas of their field of vision and cannot see objects to their right and left. Extending from the optic chiasm, the axons of the visual system are referred to as the optic tract instead of the optic nerve. The optic tract has three major targets, two in the diencephalon and one in the midbrain. The connection between the eyes and diencephalon is demonstrated during development, in which the neural tissue of the retina differentiates from that of the diencephalon by the growth of the secondary vesicles. The connections of the retina into the CNS are a holdover from this developmental association. The majority of the connections of the optic tract are to the thalamus\u2014specifically, the lateral geniculate nucleus. Axons from this nucleus then project to the visual cortex of the cerebrum, located in the occipital lobe. Another target of the optic tract is the superior colliculus. In addition, a very small number of RGC axons project from the optic chiasm to the suprachiasmatic nucleus of the hypothalamus. These RGCs are photosensitive, in that they respond to the presence or absence of light. Unlike the photoreceptors, however, these photosensitive RGCs cannot be used to perceive images. By simply responding to the absence or presence of light, these RGCs can send information about day length. The perceived proportion of sunlight to darkness establishes the circadian rhythm of our bodies, allowing certain physiological events to occur at approximately the same time every day.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Systemic mycoses spread to internal organs, most commonly entering the body through this?","choices":["infestation system","respiratory system","digestive system","skeletal system"],"answer":"B","rationale":"Systemic mycoses spread to internal organs, most commonly entering the body through the respiratory system. For example, coccidioidomycosis (valley fever) is commonly found in the southwestern United States, where the fungus resides in the dust. Once inhaled, the spores develop in the lungs and cause symptoms similar to those of tuberculosis. Histoplasmosis is caused by the dimorphic fungus Histoplasma capsulatum. It also causes pulmonary infections, and in rarer cases, swelling of the membranes of the brain and spinal cord. Treatment of these and many other fungal diseases requires the use of antifungal medications that have serious side effects. Opportunistic mycoses are fungal infections that are either common in all environments, or part of the normal biota. They mainly affect individuals who have a compromised immune system. Patients in the late stages of AIDS suffer from opportunistic mycoses that can be life threatening. The yeast Candida sp. , a common member of the natural biota, can grow unchecked and infect the vagina or mouth (oral thrush) if the pH of the surrounding environment, the person\u2019s immune defenses, or the normal population of bacteria are altered. Mycetismus can occur when poisonous mushrooms are eaten. It causes a number of human fatalities during mushroompicking season. Many edible fruiting bodies of fungi resemble highly poisonous relatives, and amateur mushroom hunters are cautioned to carefully inspect their harvest and avoid eating mushrooms of doubtful origin. The adage \u201cthere are bold mushroom pickers and old mushroom pickers, but are there no old, bold mushroom pickers\u201d is unfortunately true.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The three features that are unique to the large intestine are the teniae coli, haustra, and what?","choices":["binary appendages","disc appendages","radial appendages","epiploic appendages"],"answer":"D","rationale":"Anatomy Three features are unique to the large intestine: teniae coli, haustra, and epiploic appendages (Figure 23.23). The teniae coli are three bands of smooth muscle that make up the longitudinal muscle layer of the muscularis of the large intestine, except at its terminal end. Tonic contractions of the teniae coli bunch up the colon into a succession of pouches called haustra (singular = hostrum), which are responsible for the wrinkled appearance of the colon. Attached to the teniae coli are small, fat-filled sacs of visceral peritoneum called epiploic appendages. The purpose of these is unknown. Although the rectum and anal canal have neither teniae coli nor haustra, they do have well-developed layers of muscularis that create the strong contractions needed for defecation.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Most living things build proteins from the same 20 different what?","choices":["amino acids","atomic isolates","acid peptides","uncommon acids"],"answer":"A","rationale":"if the salt produced is an acidic salt.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What reaction, along with photosynthesis, provides energy to the vast majority of living things?","choices":["primarily respiration","devices respiration","cellular respiration","Internal Respiration"],"answer":"C","rationale":"The chemical reactions of photosynthesis and cellular respiration together provide energy to virtually all living things on Earth.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some animals increase body fat in winter to stay?","choices":["cold","warm","aware","thin"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Coal, oil, and natural gas are examples of what, which forms when organic matter is under pressure for millions of years?","choices":["complex carbohydrates","nuclear fission","fossil fuels","solar fuels"],"answer":"C","rationale":"Millions of years ago, there were so many dead plants and animals that they could not completely decompose before they were buried. They were covered over by soil or sand, tar or ice. These dead plants and animals are organic matter made out of cells full of carbon-containing organic compounds (carbohydrates, lipids, proteins and nucleic acids). What happened to all this carbon? When organic matter is under pressure for millions of years, it forms fossil fuels. Fossil fuels are coal, oil, and natural gas.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Protists play critically important ecological roles as producers and, on the other end of food webs, as what?","choices":["absorbers","decomposers","probiotics","dissolvers"],"answer":"B","rationale":"Beneficial Protists Protists play critically important ecological roles as producers particularly in the world\u2019s oceans. They are equally important on the other end of food webs as decomposers. Protists as Food Sources Protists are essential sources of nutrition for many other organisms. In some cases, as in plankton, protists are consumed directly. Alternatively, photosynthetic protists serve as producers of nutrition for other organisms by carbon fixation. For instance, photosynthetic dinoflagellates called zooxanthellae pass on most of their energy to the coral polyps that house them (Figure 13.19). In this mutually beneficial relationship, the polyps provide a protective environment and nutrients for the zooxanthellae. The polyps secrete the calcium carbonate that builds coral reefs. Without dinoflagellate symbionts, corals lose algal pigments in a process called coral bleaching, and they eventually die. This explains why reef-building corals do not reside in waters deeper than 20 meters: Not enough light reaches those depths for dinoflagellates to photosynthesize.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where do physical laws govern energy flow and chemical cycling?","choices":["ecosystems","environments","habitats","oceans"],"answer":"A","rationale":"55.1 Physical laws govern energy flow and chemical cycling in ecosystems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The distribution of thermal speeds depends strongly on temperature. as temperature increases, the speeds are shifted to higher values and the distribution is what?","choices":["removed","decreased","broadened","improved"],"answer":"C","rationale":"The distribution of thermal speeds depends strongly on temperature. As temperature increases, the speeds are shifted to higher values and the distribution is broadened.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Carbohydrates, proteins, lipids, and nucleic acids are the four classes of what type of compounds?","choices":["chromosomal compounds","reversible compounds","nutrient compounds","biochemical compounds"],"answer":"D","rationale":"Carbohydrates are one of four classes of biochemical compounds. The other three classes are proteins, lipids, and nucleic acids. In addition to cellulose, carbohydrates include sugars and starches. Carbohydrate molecules contain atoms of carbon, hydrogen, and oxygen. Living things use carbohydrates mainly for energy. For more in-depth information on carbohydrates, you may want to watch the videos at these URLs:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most important factor in soil formation?","choices":["carbon","fertilizer","worms","climate"],"answer":"D","rationale":"Climate is the most important factor in soil formation. The climate of a region is the result of its temperature and rainfall. We can identify different climates by the plants that grow there ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the outer layer of cells in a root called?","choices":["epidermis","muscles","igneous","skeletal"],"answer":"A","rationale":"The root has an outer layer of cells called the epidermis, which surrounds areas of ground tissue and vascular tissue. The epidermis provides protection and helps in absorption. Root hairs, which are extensions of root epidermal cells, increase the surface area of the root, greatly contributing to the absorption of water and minerals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of feeders are the largest sharks and rays?","choices":["resting feeders","suspension feeders","month feeders","resulting feeders"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Chemical digestion couldn't take place without the help of what?","choices":["melatonin","digestive enzymes","pigments","neurotransmitters"],"answer":"B","rationale":"Chemical digestion could not take place without the help of digestive enzymes. An enzyme is a protein that speeds up chemical reactions in the body. Digestive enzymes speed up chemical reactions that break down large food molecules into small molecules.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where would you find three tiny bones called the hammer, anvil, and stirrup?","choices":["neck","tail bone","foot","middle ear"],"answer":"D","rationale":"The middle ear contains three tiny bones (ossicles) called the hammer, anvil, and stirrup. If you look at these bones in the Figure above , you might notice that they resemble the objects for which they are named. The three bones transmit vibrations from the eardrum to the inner ear. The arrangement of the three bones allows them to work together as a lever that increases the amplitude of the waves as they pass to the inner ear.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Energy resources can be put into two categories \u2014 renewable or?","choices":["precious","nonrenewable","reusable","synthetic"],"answer":"B","rationale":"Energy resources can be put into two categories \u2014 renewable or non-renewable. Nonrenewable resources are used faster than they can be replaced. Renewable resources can be replaced as quickly as they are used. Renewable resources may also be so abundant that running out is impossible.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Even the age of earth has been estimated on the basis of what?","choices":["gasses","tree rings","membranes","radioisotopes"],"answer":"D","rationale":"Radioactive isotopes, or radioisotopes, can be used to estimate the ages of not only of rocks, but also of fossils and artifacts made long ago by human beings. Even the age of Earth has been estimated on the basis of radioisotopes. The general method is called radioactive dating . To understand how radioactive dating works, you need to understand radioisotopes and radioactive decay.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In the primary response to infection, what are secreted first from plasma cells?","choices":["pathogens","platelets","antibodies","parasites"],"answer":"C","rationale":"Figure 17.18 In the primary response to infection, antibodies are secreted first from plasma cells. Upon re-exposure to the same pathogen, memory cells differentiate into antibody-secreting plasma cells that output a greater amount of antibody for a longer period of time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A hookworm is classified as what type of organism?","choices":["predator","bacterium","virus","parasite"],"answer":"D","rationale":"Parasites may live either inside or on the surface of their host. An example of a parasite is a hookworm. Hookworms are roundworms that affect the small intestine and lungs of a host organism. They live inside of humans and cause them pain. However, the hookworms must live inside of a host in order to survive. Parasites may even kill the host they live on, but then they also kill their host organism, so this is rare. Parasites are found in animals, plants, and fungi. Hookworms are common in the moist tropic and subtropic regions. There is very little risk of getting a parasite in industrialized nations.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A pigment within plant cells which absorbs light is called?","choices":["carbonate","xylem","green","chlorophyll"],"answer":"D","rationale":"chlorophyll - a pigment within plant cells which absorbs light.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where does slime mold typically live?","choices":["in the jungle","in the soil and in glaciers","decaying plant life and in the soil","in the sea"],"answer":"C","rationale":"Slime molds live on decaying plant life and in the soil.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Genital warts is an sti caused by what?","choices":["human conoil virus","human papova virus","human papilloma virus","human polyoma virus"],"answer":"C","rationale":"Genital warts is an STI caused by human papilloma virus (HPV), which is pictured in Figure below . This is one of the most common STIs in U. S. teens. Genital warts can\u2019t be cured, but a vaccine can prevent most HPV infections. The vaccine is recommended for boys and girls starting at 11 or 12 years of age. It\u2019s important to prevent HPV infections because they may lead to cancer later in life.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do ectotherms use to regulate body temperature?","choices":["Flexible Energy Source","combustion energy sources","external energy sources","result energy sources"],"answer":"C","rationale":"Ectotherms, sometimes called cold-blooded animals, do not use the energy of metabolism to regulate body temperature. Instead, they depend on external energy sources, such as sunlight. Fish, for example, will seek out water of different temperatures to regulate body temperature. The amount of energy available is directly related to the metabolic rate of the animal. When energy is scarce, ectotherms may also hibernate. The connection between metabolism and body temperature is a reminder that energy and chemical reactions are intimately related. A basic understanding of this relationship is especially important when those chemical reactions occur within our own bodies. Energy is a vital component of the world around us. Nearly every physical and chemical process, including all the chemical reactions discussed in previous chapters, occurs with a simultaneous energy change. In this chapter, we will explore the nature of energy and how energy and chemistry are related.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What event occurred at the close of the precambrian era?","choices":["natural selection","ecosystem succession","spontaneous mutation","a mass extinction"],"answer":"D","rationale":"At the close of the Precambrian 544 million years ago, a mass extinction occurred. In a mass extinction , many or even most species abruptly disappear from Earth. There have been five mass extinctions in Earth\u2019s history. Many scientists think we are currently going through a sixth mass extinction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A balanced equation has an equal number of what on each side?","choices":["valencies and electrons","protons and neutrons","electrons and neutrons","protons and reactions"],"answer":"B","rationale":"If you count the number of protons and neutrons on each side of this equation, you\u2019ll see that the numbers are the same on both sides of the arrow. This means that the equation is balanced. The thorium-234 produced in this reaction is unstable, so it will undergo radioactive decay as well. The alpha particle produced in the reaction can pick up two electrons to form the element helium. This is how most of Earth\u2019s helium formed.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Pure substances have a constant composition and can only be changed by what?","choices":["chemical reactions","growth","radiation","carbon reactions"],"answer":"A","rationale":"Pure substances have a constant composition and can only be changed by chemical reactions. They can be classified as either elements or compounds.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Earthquakes occur most often at which natural feature?","choices":["artificial boundaries","pattern boundaries","plate boundaries","plate holes"],"answer":"C","rationale":"The vast majority of earthquakes happen at plate boundaries.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How many atmospheric circulation cells are there?","choices":["six","two","three","five"],"answer":"A","rationale":"The globe has six atmospheric circulation cells. Three are north of the Equator and three are south. These cells have names.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Proper chemical formulas for ionic compounds balance the total positive charge with what?","choices":["total electric charge","total atomic charge","total negative charge","total ionic charge"],"answer":"C","rationale":"Proper chemical formulas for ionic compounds balance the total positive charge with the total negative charge.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which process helps microorganisms make food with chemicals pouring out of deep-sea vents?","choices":["biosynthesis","photosynthesis","synaptogenesis","chemosynthesis"],"answer":"D","rationale":"There are many more organisms around deep-sea vents. Microorganisms use chemicals that pour out of the vents to make food by chemosynthesis. These producers support large numbers of other organisms, including crustaceans and red tubeworms like those pictured in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a combination of two or more substances in any proportion called?","choices":["combination","solvent","solution","mixture"],"answer":"D","rationale":"Not all combined substances are compounds. Some are mixtures. A mixture is a combination of two or more substances in any proportion. The substances in a mixture may be elements or compounds. The substances don\u2019t combine chemically to form a new substance, as they do in a compound. Instead, they keep their original properties and just intermix. Examples of mixtures include salt and water in the ocean and gases in the atmosphere. Other examples are pictured in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where is the youngest seafloor located?","choices":["at the base","at the floor","at the ridge","at the reefs"],"answer":"C","rationale":"The youngest seafloor is at the ridge. The oldest is farthest from the ridge. The oldest seafloor is much younger than the oldest continent.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of mixture consists of two or more phases, exemplified when a combination of oil and water forms layers?","choices":["complex miture","simple mixture","heterogeneous","homogeneous"],"answer":"C","rationale":"A phase is any part of a sample that has a uniform composition and properties. By definition, a pure substance or a homogeneous mixture consists of a single phase. A heterogeneous mixture consists of two or more phases. When oil and water are combined, they do not mix evenly, but instead form two separate layers. Each of the layers is called a phase.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The values of strangeness assigned to various particles are based on what?","choices":["atomic mass","decay systematics","thermal energy","penetration potential"],"answer":"B","rationale":"lifetimes on the order of 10 s (the exception is \u03a3 , whose short lifetime is explained by its particular quark substructure. ), implying that their decay is caused by the weak force alone, although they are hadrons and feel the strong force. The decay modes of these particles also show patterns\u2014in particular, certain decays that should be possible within all the known conservation laws do not occur. Whenever something is possible in physics, it will happen. If something does not happen, it is forbidden by a rule. All this seemed strange to those studying these particles when they were first discovered, so they named a new quantum number strangeness, given the symbol S in the table given above. The values of strangeness assigned to various particles are based on the decay systematics. It is found that strangeness is conserved by the strong force, which.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Together, the muscular and skeletal organs are known as what?","choices":["cardiovascular system","lymphatic system","musculoskeletal system","nervous system"],"answer":"C","rationale":"CHAPTER REVIEW 6.1 The Functions of the Skeletal System The major functions of the bones are body support, facilitation of movement, protection of internal organs, storage of minerals and fat, and hematopoiesis. Together, the muscular system and skeletal system are known as the musculoskeletal system.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do factories and power plants use to remove particulates and waste gases from exhaust before releasing it?","choices":["scrubbers","compressors","catalytic converters","mufflers"],"answer":"A","rationale":"Scrubbers are used in factories and power plants. They remove particulates and waste gases from exhaust before it is released to the air. You can see how a scrubber works in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Humans typically have how many pairs of chromosomes?","choices":["14 pairs","17 pairs","23 pairs","25 pairs"],"answer":"C","rationale":"No, you only received half of your mother's chromosomes and half of your father's chromosomes. If you inherited them all, you would have twice the number of chromosomes that you're supposed to have. Humans typically have 23 pairs of chromosomes. If you received all your parents' chromosomes, you would have 46 pairs!.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Correlation is different from what term that refers to the factor that is producing the effect?","choices":["causation","manifestation","correlation","differentiation"],"answer":"A","rationale":"But correlation does not necessarily indicate causation. Causation refers to the factor that is producing the effect. If I push a toy car, I will cause it to move. To explain the difference between correlation and causation, let\u2019s look at an example. Sugar consumption in the United States has been rising for decades ( Figure below ). There is a positive correlation between sugar consumption and rising average global temperatures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What organelles do animal cells use to convert food into energy?","choices":["flagellum","nucleus","endoplasmic reticulum","mitochondria"],"answer":"D","rationale":"When an animal needs energy, it eats food. That's why animals use mitochondria to convert food into energy. Plants, on the other hand, don't seem to eat anything. Instead, they receive energy from water and sunlight. They use chloroplasts to convert light into energy through photosynthesis. The focus of this concept is to delineate the distinct differences between plant and animal cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where does egg production happen?","choices":["fallopian tube","testes","uterus","ovaries"],"answer":"D","rationale":"Egg production takes place in the ovaries. It takes several steps to make an egg:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What can be used to estimate the energy change of a chemical reaction?","choices":["chemical energy","bond magnitudes","bond energies","isoenergies"],"answer":"C","rationale":"Bond energies can be used to estimate the energy change of a chemical reaction. When bonds are broken in the reactants, the energy change for this process is endothermic. When bonds are formed in the products, the energy change for this process is exothermic. We combine the positive energy change with the negative energy change to estimate the overall energy change of the reaction. For example, in.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Destructive interference occurs when two identical waves are superimposed exactly out of phase. a standing wave is one in which two waves superimpose to produce a wave that varies in amplitude but does not do this?","choices":["substrate","membrane","propagate","reproduce"],"answer":"C","rationale":"Superposition is the combination of two waves at the same location. Constructive interference occurs when two identical waves are superimposed in phase. Destructive interference occurs when two identical waves are superimposed exactly out of phase. A standing wave is one in which two waves superimpose to produce a wave that varies in amplitude but does not propagate. Nodes are points of no motion in standing waves. An antinode is the location of maximum amplitude of a standing wave. Waves on a string are resonant standing waves with a fundamental frequency and can occur at higher multiples of the fundamental, called overtones or harmonics. Beats occur when waves of similar frequencies f 1 and f 2 are superimposed. The resulting amplitude oscillates with a beat frequency given by.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the layer outside the cell wall in a prokaryote?","choices":["capsule","membrane","pod","rim"],"answer":"A","rationale":"Many prokaryotes have another layer, called a capsule, outside the cell wall. The capsule protects the cell from chemicals and drying out. It also allows the cell to stick to surfaces and to other cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What delivers natural gas from rock that might not otherwise be obtainable?","choices":["rippling","fracking","drilling","grinding"],"answer":"B","rationale":"Fracking delivers natural gas from rock that might not otherwise be obtainable.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Name the white blood cells that can squeeze through capillary walls and swallow particles.","choices":["neutrophils","hemoglobin","platelets","lymphocytes"],"answer":"A","rationale":"Neutrophils are WBCs that can squeeze through capillary walls and swallow particles such as bacteria and parasites.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Permanent dipole-dipole interactions are found in what kind of molecules?","choices":["polar","directional","dual","geologic"],"answer":"A","rationale":"Polar molecules have permanent dipole-dipole interactions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The energy released during an earthquake is called what?","choices":["magnitude","tidal","hydro","radiation"],"answer":"A","rationale":"The ways seismologists measure an earthquake have changed over the decades. Initially, they could only measure what people felt and saw, the intensity. Now they can measure the energy released during the quake, the magnitude.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Many replication forks develop along a what?","choices":["nucleus","genome","chromosome","allele"],"answer":"C","rationale":"Many replication forks develop along a chromosome. This process continues until the replication forks meet, and the all of the DNA in a chromosome has been copied. Each new strand that has formed is complementary to the strand used as the template. Each resulting DNA molecule is identical to the original DNA molecule. During prophase of mitosis or prophase I of meiosis, these molecules of DNA condense into a chromosome made of two identical \"sister\" chromatids. This process ensures that cells that result from cell division have identical sets of genetic material, and that the DNA is an exact copy of the parent cell\u2019s DNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the strength of an acid or base?","choices":["carbon","pH","texture","acidity"],"answer":"D","rationale":"The strength of an acid or base is called acidity. It depends on how much of the substance breaks down into ions when it dissolves in water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A bog is a type of ____","choices":["lake","plant","wetland","stream"],"answer":"C","rationale":"Not all wetlands are alike, as you can see below ( Figure below ). Wetlands vary in how wet they are and how much of the year they are soaked. Wetlands also vary in the kinds of plants that live in them. This depends mostly on the climate where the wetland is found. Types of wetlands include marshes, swamps, and bogs.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In projectile motion, the horizontal displacement of an object is called its what?","choices":["variety","width","height","range"],"answer":"D","rationale":"In projectile motion, the horizontal displacement of an object is called its range .","split":"validation","source_dataset":"sciq","subject":null},{"question":"An oil drop is stationary when what downward force exactly equals the upward electrical force on the drop?","choices":["newtonian","magnetic","gravitational","radiation"],"answer":"C","rationale":"The charge on the plates is adjustable. By measuring the terminal velocity of the oil drops with the electric field off, Millikan could determine the mass of the drops. Millikan and his graduate assistant were able to determine the force of the field on the drops when it was turned on by comparing the velocity of the drops with the field on to their velocity with the field off. This is easily determined when the oil drop is stationary; namely, when the downward gravitational force exactly equals the upward electrical force on the drop.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The secretion of what may influence the body\u2019s circadian rhythms?","choices":["serotonin","melatonin","human growth hormone","testosterone"],"answer":"B","rationale":"The secretion of melatonin may influence the body\u2019s circadian rhythms, the dark-light fluctuations that affect not only sleepiness and wakefulness, but also appetite and body temperature. Interestingly, children have higher melatonin levels than adults, which may prevent the release of gonadotropins from the anterior pituitary, thereby inhibiting the onset of puberty. Finally, an antioxidant role of melatonin is the subject of current research. Jet lag occurs when a person travels across several time zones and feels sleepy during the day or wakeful at night. Traveling across multiple time zones significantly disturbs the light-dark cycle regulated by melatonin. It can take up to several days for melatonin synthesis to adjust to the light-dark patterns in the new environment, resulting in jet lag. Some air travelers take melatonin supplements to induce sleep.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Photosynthesis takes the energy of sunlight and combines water and carbon dioxide to produce sugar and oxygen as this?","choices":["secondary product","primary product","reactive product","waste product"],"answer":"D","rationale":"The free electron travels through the electron transport chain, and the energy of the electron is used to pump hydrogen ions into the thylakoid space, transferring the energy into the electrochemical gradient. The energy of the electrochemical gradient is used to power ATP synthase, and the energy is transferred into a bond in the ATP molecule. In addition, energy from another photon can be used to create a high-energy bond in the molecule NADPH. 16 Photosynthesis takes the energy of sunlight and combines water and carbon dioxide to produce sugar and oxygen as a waste product. The reactions of respiration take sugar and consume oxygen to break it down into carbon dioxide and water, releasing energy. Thus, the reactants of photosynthesis are the products of respiration, and vice versa.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Purkinje fibers have a fast inherent what?","choices":["conduction rate","replication rate","induction rate","electromagnetic rate"],"answer":"A","rationale":"Atrioventricular Bundle (Bundle of His), Bundle Branches, and Purkinje Fibers Arising from the AV node, the atrioventricular bundle, or bundle of His, proceeds through the interventricular septum before dividing into two atrioventricular bundle branches, commonly called the left and right bundle branches. The left bundle branch has two fascicles. The left bundle branch supplies the left ventricle, and the right bundle branch the right ventricle. Since the left ventricle is much larger than the right, the left bundle branch is also considerably larger than the right. Portions of the right bundle branch are found in the moderator band and supply the right papillary muscles. Because of this connection, each papillary muscle receives the impulse at approximately the same time, so they begin to contract simultaneously just prior to the remainder of the myocardial contractile cells of the ventricles. This is believed to allow tension to develop on the chordae tendineae prior to right ventricular contraction. There is no corresponding moderator band on the left. Both bundle branches descend and reach the apex of the heart where they connect with the Purkinje fibers (see Figure 19.19, step 4). This passage takes approximately 25 ms. The Purkinje fibers are additional myocardial conductive fibers that spread the impulse to the myocardial contractile cells in the ventricles. They extend throughout the myocardium from the apex of the heart toward the atrioventricular septum and the base of the heart. The Purkinje fibers have a fast inherent conduction rate, and the electrical impulse reaches all of the ventricular muscle cells in about 75 ms (see Figure 19.19, step 5). Since the electrical stimulus begins at the apex, the contraction also begins at the apex and travels toward the base of the heart, similar to squeezing a tube of toothpaste from the bottom. This allows the blood to be pumped out of the ventricles and into the aorta and pulmonary trunk. The total time elapsed from the initiation of the impulse in the SA node until depolarization of the ventricles is approximately 225 ms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What process affecting genes or chromosomes causes genetic disorders?","choices":["graduation","radiation","mutation","infection"],"answer":"C","rationale":"Many genetic disorders are caused by mutations in one or a few genes. Others are caused by chromosomal mutations. Some human genetic disorders are X-linked or Y-linked, which means the faulty gene is carried on these sex chromosomes. Other genetic disorders are carried on one of the other 22 pairs of chromosomes; these chromosomes are known as autosomes or autosomal (non-sex) chromosomes. Some genetic disorders are due to new mutations, others can be inherited from your parents.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of engine burns fuel to heat water and produce steam?","choices":["condensation","combustion","convection","conduction"],"answer":"B","rationale":"An external combustion engine burns fuel to heat water and produce steam. The steam is under pressure and is used to push a piston back and forth inside a cylinder. As the piston moves back and forth, it moves a piston rod, which can do work.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Oncogenesis is one name for the process where normal cells turn into what?","choices":["blood cells","lung cells","cancer cells","brain cells"],"answer":"C","rationale":"Carcinogenesis is the process by which normal cells are transformed into cancer cells. The process is also known as oncogenesis or tumorigenesis and it depends on both the activation of oncogenes and deactivation of tumor suppressor genes . Proto-oncogenes, the non-cancerous normal version of an oncogene, can be a transcription factor like c-fos, c-jun and c-myc, or a gene whose product is involved in signal transduction, leading to altered gene expression. When mutations cause the regulation of this process to be disturbed, cell proliferation can be enhanced leading to tumorigenesis.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Characteristics of an organism are passed from one generation to the next through what?","choices":["eggs","genes","ribosomes","sperm"],"answer":"B","rationale":"Characteristics of organisms are passed from one generation to the next through their genes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Reactants are substances that start what?","choices":["growth reaction","chemical reaction","dying reaction","consumption reaction"],"answer":"B","rationale":"Reactants are substances that start a chemical reaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are cyclic compounds which have an element other than carbon atoms in the ring?","choices":["axial compounds","homocyclic compounds","polymeric compounds","heterocyclic compounds"],"answer":"D","rationale":"Note So far we have studied only aromatic compounds with carbon-containing rings. However, many cyclic compounds have an element other than carbon atoms in the ring. These compounds, called heterocyclic compounds, are discussed inChapter 15 \"Organic Acids and Bases and Some of Their Derivatives\", Section 15.13 \"Amines as Bases\". Some of these are heterocyclic aromatic compounds. Table 13.4 Some Drugs That Contain a Benzene Ring.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Surviving megaspores develop into what?","choices":["null gametophytes","singular celled female gametophytes","multicellular male gametophytes","multicellular female gametophytes"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Stoichiometry is concerned with the reactants and the products in chemical what?","choices":["solvents","reactions","photosynthesis","bonds"],"answer":"B","rationale":"numerical relationships between the reactants and the products in balanced chemical reactions is called stoichiometry.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call the angle at which waves strike a wall?","choices":["rotation of incidence","incidence impact","angle of incidence","angle of impact"],"answer":"C","rationale":"Waves strike a wall at an angle, called the angle of incidence. The waves are reflected at the same angle, called the angle of reflection, but in a different direction. Both angles are measured relative to a line that is perpendicular to the wall.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nitrogen & sulfur oxide combine with rain to form what?","choices":["acid rain","toxic rain","steam rain","coarse rain"],"answer":"A","rationale":"Nitrogen and sulfur oxides combine with rain to form acid rain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The nitrogenous bases found in nucleotides are classified as pyrimidines or what?","choices":["Fallen","purines","Science","terpenes"],"answer":"B","rationale":"The nitrogenous bases found in nucleotides are classified as pyrimidines or purines. Pyrimidines are heterocyclic amines with two nitrogen atoms in a six-member ring and include uracil, thymine, and cytosine. (For more information about heterocyclic amines, see Chapter 15 \"Organic Acids and Bases and Some of Their Derivatives\", Section 15.13 \"Amines as Bases\". ) Purines are heterocyclic amines consisting of a pyrimidine ring fused to a five-member ring with two nitrogen atoms. Adenine and guanine are the major purines found in nucleic acids (Figure 19.2 \"The Nitrogenous Bases Found in DNA and RNA\"). Figure 19.2 The Nitrogenous Bases Found in DNA and RNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Instead of heat, organisms use what to speed up reactions?","choices":["catalysis","acids","synthesis","metabolism"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term in science describes not just a guess, but a well-formed set of explanations for a phenomenon?","choices":["evolution","concept","theory","hypothesis"],"answer":"C","rationale":"Some ideas in science gain the status of theories. Scientists use the term \"theory\" differently than it is used in everyday language. You might say, \"I think the dog ate my homework, but it\u2019s just a theory. \" In other words, it\u2019s just one of many possible explanations for the missing work. However, in science, a theory is much more than that.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Although helper t cells do not destroy infected or damaged body cells, they are still necessary for what?","choices":["brain response","immune response","mutations response","lung response"],"answer":"B","rationale":"Helper T cells do not destroy infected or damaged body cells. But they are still necessary for an immune response. They help by releasing chemicals that control other lymphocytes. The chemicals released by helper T cells \u201cswitch on\u201d both B cells and killer T cells so they can recognize and fight specific pathogens.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The seven unique crystal types are defined by what parts of themselves (parts that intersect at various angles)?","choices":["angles","eyes","faces","shards"],"answer":"C","rationale":"Crystals are classified into general categories based on their shapes. A crystal is defined by its faces, which intersect with one another at specific angles, which are characteristic of the given substance. The seven crystal systems are shown below, along with an example of each. The edge lengths of a crystal are represented by the letters , , and . The angles at which the faces intersect are represented by the Greek letters , , and . Each of the seven crystal systems differs in terms of the angles between the faces and in the number of edges of equal length on each face.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In their processes of gene expression, archael cells show similarties to both bacterial cells and which other type of cell?","choices":["Prokaryotic","chloroplasts","eukaryotic","plant cells"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term refers to the amount of solute that can dissolve in a given amount of solvent at a given temperature?","choices":["turbidity","viscosity","solubility","saturation"],"answer":"C","rationale":"Solubility is the amount of solute that can dissolve in a given amount of solvent at a given temperature. Some solutes have greater solubility than others.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Although quite different, beryllium, magnesium, calcium, strontium, barium, and radium are all classified as what type of metals?","choices":["alkaline earth metals","acidic earth metals","detergent earth metals","mucous earth metals"],"answer":"A","rationale":"The Alkaline Earth Metals The alkaline earth metals are beryllium, magnesium, calcium, strontium, barium, and radium. Beryllium, strontium, and barium are rather rare, and radium is unstable and highly radioactive. In contrast, calcium and magnesium are the fifth and sixth most abundant elements on Earth, respectively; they are found in huge deposits of limestone and other minerals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What predatory mammal is the fastest land animal on earth?","choices":["panther","cheetah","tiger","giraffe"],"answer":"B","rationale":"Mammals are noted for the many ways they can move about. Generally, their limbs are very mobile. Often, they can be rotated. Many mammals are also known for their speed. The fastest land animal is a predatory mammal. Can you guess what it is? Racing at speeds of up to 112 kilometers (70 miles) per hour, the cheetah wins hands down. In addition, the limbs of mammals let them hold their body up above the ground. That\u2019s because the limbs are attached beneath the body, rather than at the sides as in reptiles (see Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why did woolly mammoths began to go extinct thousands of years ago?","choices":["parasites","hunting by humans","volcanic eruptions","competition for food"],"answer":"B","rationale":"Woolly mammoths began to go extinct about 10,000 years ago, soon after paleontologists believe humans able to hunt them began to colonize North America and northern Eurasia (Figure 19.8). A mammoth population survived on Wrangel Island, in the East Siberian Sea, and was isolated from human contact until as recently as 1700 BC. We know a lot about these animals from carcasses found frozen in the ice of Siberia and other northern regions. It is commonly thought that climate change and human hunting led to their extinction. A 2008 study estimated that climate change reduced the mammoth\u2019s range from 3,000,000 square miles 42,000 years [3] ago to 310,000 square miles 6,000 years ago. Through archaeological evidence of kill sites, it is also well documented that humans hunted these animals. A 2012 study concluded that no single factor was [4] exclusively responsible for the extinction of these magnificent creatures. In addition to climate change and reduction of habitat, scientists demonstrated another important factor in the mammoth\u2019s extinction was the migration of human hunters across the Bering Strait to North America during the last ice age 20,000 years ago. The maintenance of stable populations was and is very complex, with many interacting factors determining the outcome. It is important to remember that humans are also part of nature. Once we contributed to a species\u2019 decline using primitive hunting technology only.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a developing baby called in the very early stages?","choices":["embryo","sperm","fetus","uterus"],"answer":"A","rationale":"While a woman is pregnant, the developing baby may be called an embryo or a fetus. Do these mean the same thing? No, in the very early stages the developing baby is called an embryo, while in the later stages it is called a fetus. When the ball of cells first implants into the uterus, it is called an embryo . The embryo stage lasts until the end of the 8 th week after fertilization. After that point until birth, the developing baby is called a fetus .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is released when an atom gains valence electrons and forms a negative ion?","choices":["fusion","energy","charge","heat"],"answer":"B","rationale":"It takes energy to remove valence electrons from an atom and form a positive ion. Energy is released when an atom gains valence electrons and forms a negative ion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of matter that mechanical wave energy can only travel through?","choices":["weight","solid","medium","form"],"answer":"C","rationale":"The energy of a mechanical wave can travel only through matter. This matter is called the medium ( plural , media). The medium in Figure above is a liquid \u2014 the water in the pond. But the medium of a mechanical wave can be any state of matter, including a solid or a gas. It\u2019s important to note that particles of matter in the medium don\u2019t actually travel along with the wave. Only the energy travels. The particles of the medium just vibrate, or move back-and-forth or up-and-down in one spot, always returning to their original positions. As the particles vibrate, they pass the energy of the disturbance to the particles next to them, which pass the energy to the particles next to them, and so on.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is able to occur because no surface is perfectly smooth?","choices":["mass","friction","temperature","tension"],"answer":"B","rationale":"Friction occurs because no surface is perfectly smooth. Even surfaces that look smooth to the unaided eye appear rough or bumpy when viewed under a microscope. Look at the metal surfaces in Figure below . The metal foil is so smooth that it is shiny. However, when highly magnified, the surface of metal appears to be very bumpy. All those mountains and valleys catch and grab the mountains and valleys of any other surface that contacts the metal. This creates friction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What determines the reactivity of an atom?","choices":["valence electrons","neutral electrons","unstable electrons","reactive electrons"],"answer":"A","rationale":"Valence electrons determine the reactivity of an atom.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the fusing of two or more smaller nuclei to form a single, larger nucleus?","choices":["likely fusion","nuclear fusion","atomic fusion","radiactive fusion"],"answer":"B","rationale":"Nuclear fusion is the fusing of two or more smaller nuclei to form a single, larger nucleus. Fusion releases even more energy than fission. Researchers are trying to find a way to use the energy from nuclear fusion to generate electricity.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of the plant absorbs water?","choices":["flower","leaves","stem","roots"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the attraction between oppositely charged atoms or ions?","choices":["magnetic bond","neutron bond","covalent bond","ionic bond"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the outer planets of the solar system made of?","choices":["liquids","gases","plasma","solids"],"answer":"B","rationale":"The inner planets are small and rocky, while the outer planets are large and made of gases. Why might the planets have formed into these two groups?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Allergy symptoms can be treated with medications such as?","choices":["antihistamines","hormone treatments","antibiotics","channel blockers"],"answer":"A","rationale":"Allergy symptoms can range from mild to severe. Mild symptoms might include itchy eyes, sneezing, and a runny nose. Severe symptoms can cause difficulty breathing, which may be life threatening. Keep in mind that it is the immune system and not the allergen that causes the allergy symptoms. Allergy symptoms can be treated with medications such as antihistamines. Severe allergic reactions may require an injection of the hormone epinephrine. These treatments lessen or counter the immune system\u2019s response.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is considered to be the most common intrusive igneous rock?","choices":["basalt","sandstone","obsidian","granite"],"answer":"D","rationale":"Granite is the most common intrusive igneous rock. Pictured below are four types of intrusive rocks ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which type of carbohydrate is glucose?","choices":["fluid","compound","simple","sweet"],"answer":"C","rationale":"Sugars are simple carbohydrates such as glucose, which the cells of living things use for energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What obstructs people from seeing the milky way at night?","choices":["the Moon","myopia","light pollution","coriolis effect"],"answer":"C","rationale":"There is so much light pollution in most cities that many people have never seen the Milky Way. On a clear night away from lights, the view is of a bright white river of stars. You don't need a telescope or even binoculars to see it. The view of the Milky Way is so bright because you're looking at the stars in your own galaxy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The north end of a compass needle points toward which of earth's magnetic poles?","choices":["west","south","west","north"],"answer":"D","rationale":"Q: The north end of a compass needle points toward Earth\u2019s north magnetic pole. The like poles of two magnets repel each other, and the opposite poles attract. So why doesn\u2019t the north end of a compass needle point to Earth\u2019s south magnetic pole instead?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Deer, rabbits and mice are an example of what link between producers and other consumers?","choices":["herbivores","mammals","carnivores","amphibians"],"answer":"A","rationale":"Herbivores consume producers such as plants or algae. They are a necessary link between producers and other consumers. Examples include deer, rabbits, and mice.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the process of creating offspring from just one individual animal?","choices":["ideal reproduction","sexual reproduction","organic reproduction","asexual reproduction"],"answer":"D","rationale":"No, not all animals have two parents. When necessary, some animals can be produced from just one parent. Some reptiles, such as this Komodo dragon, have only one parent. The process of creating offspring from just one individual is called asexual reproduction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Strength, the ability of a muscle to use force during a contraction, differs from what term meaning the ability of a muscle to continue to contract over time without getting tired?","choices":["recovery","endurance","energy","resilience"],"answer":"B","rationale":"Exercise improves both muscular strength and muscular endurance. Muscular strength is the ability of a muscle to use force during a contraction. Muscular endurance is the ability of a muscle to continue to contract over a long time without getting tired.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What disease-causing acellular entities containing either dna or rna replicate using the replication proteins of a host cell?","choices":["parasites","viruses","parasitic worms","pathogens"],"answer":"B","rationale":"CHAPTER SUMMARY 17.1 Viruses Viruses are acellular entities that can usually only be seen with an electron microscope. Their genomes contain either DNA or RNA, and they replicate using the replication proteins of a host cell. Viruses are diverse, infecting archaea, bacteria, fungi, plants, and animals. Viruses consist of a nucleic-acid core surrounded by a protein capsid with or without an outer lipid envelope. Viral replication within a living cell always produces changes in the cell, sometimes resulting in cell death and sometimes slowly killing the infected cells. There are six basic stages in the virus replication cycle: attachment, penetration, uncoating, replication, assembly, and release. A viral infection may be productive, resulting in new virions, or nonproductive, meaning the virus remains inside the cell without producing new virions. Viruses cause a variety of diseases in humans. Many of these diseases can be prevented by the use of viral vaccines, which stimulate protective immunity against the virus without causing major disease. Viral vaccines may also be used in active viral infections, boosting the ability of the immune system to control or destroy the virus. Antiviral drugs that target enzymes and other protein products of viral genes have been developed and used with mixed success. Combinations of anti-HIV drugs have been used to effectively control the virus, extending the lifespan of infected individuals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of virus is the flu caused by?","choices":["Rubella","pneumonia","Mononucleosis","influenza"],"answer":"D","rationale":"Doesn't look like fun. The flu is caused by an influenza virus. And usually a slightly different virus every season.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Almost all leaves are specialized for what process?","choices":["photosynthesis","sex","reactions","measurements"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some inhibitor molecules bind to enzymes in a location where their binding induces a conformational change that reduces the affinity of the enzyme for its substrate. this type of inhibition is called allosteric what?","choices":["secretion","mutation","induction","inhibition"],"answer":"D","rationale":"On the other hand, in noncompetitive inhibition, an inhibitor molecule binds to the enzyme in a location other than the active site, called an allosteric site, but still manages to block substrate binding to the active site. Some inhibitor molecules bind to enzymes in a location where their binding induces a conformational change that reduces the affinity of the enzyme for its substrate. This type of inhibition is called allosteric inhibition (Figure 4.9). Most allosterically regulated enzymes are made up of more than one polypeptide, meaning that they have more than one protein subunit. When an allosteric inhibitor binds to a region on an enzyme, all active sites on the protein subunits are changed slightly such that they bind their substrates with less efficiency. There are allosteric activators as well as inhibitors. Allosteric activators bind to locations on an enzyme away from the active site, inducing a conformational change that increases the affinity of the enzyme\u2019s active site(s) for its substrate(s) (Figure 4.9).","split":"validation","source_dataset":"sciq","subject":null},{"question":"During which process does carbon dioxide exit the cells, enter the bloodstream, travel back to the lungs, and get expired out of the body?","choices":["exhalation","peroxidation","osmosis","inhalation"],"answer":"A","rationale":"The Respiratory System Take a breath in and hold it. Wait several seconds and then let it out. Humans, when they are not exerting themselves, breathe approximately 15 times per minute on average. This equates to about 900 breaths an hour or 21,600 breaths per day. With every inhalation, air fills the lungs, and with every exhalation, it rushes back out. That air is doing more than just inflating and deflating the lungs in the chest cavity. The air contains oxygen that crosses the lung tissue, enters the bloodstream, and travels to organs and tissues. There, oxygen is exchanged for carbon dioxide, which is a cellular waste material. Carbon dioxide exits the cells, enters the bloodstream, travels back to the lungs, and is expired out of the body during exhalation.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Exotic species, also known as invasive or non-native species often cause _______ when introduced to new environments.","choices":["confusion","extinction","radicalization","harmony"],"answer":"B","rationale":"One of the main causes of extinction is introduction of exotic species into an environment. These exotic and new species can also be called invasive species or non-native species . These non-native species, being new to an area, may not have natural predators in the new habitat, which allows their populations to easily adapt and grow. Invasive species out-compete the native species for resources. Sometimes invasive species are so successful at living in a certain habitat that the native species go extinct ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is formed when light rays diverge behind a lens?","choices":["a projection","a hologram","a shadow","a virtual image"],"answer":"D","rationale":"When light rays diverge behind a lens, a virtual image is formed. A virtual image is a manifestation of your brain (it traces the diverging rays backwards and forms an image), like the person you see \u201cbehind\u201d a mirror\u2019s surface when you brush your teeth (there's obviously no real light focused behind a mirror!). Since virtual images aren\u2019t actually \u201canywhere,\u201d you can\u2019t place photographic film anywhere to capture them.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An equipotential line is a line along which the electric potential is wht?","choices":["increasing","changeable","decreasing","constant"],"answer":"D","rationale":"An equipotential line is a line along which the electric potential is constant. An equipotential surface is a three-dimensional version of equipotential lines. Equipotential lines are always perpendicular to electric field lines. The process by which a conductor can be fixed at zero volts by connecting it to the earth with a good conductor is called grounding.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Keratin is an intracellular fibrous protein that gives hair, nails, and skin their hardness and this?","choices":["water-resistant properties","cold - resistant properties","friction resistant properties","heat resistant properties"],"answer":"A","rationale":"The cells in all of the layers except the stratum basale are called keratinocytes. A keratinocyte is a cell that manufactures and stores the protein keratin. Keratin is an intracellular fibrous protein that gives hair, nails, and skin their hardness and water-resistant properties. The keratinocytes in the stratum corneum are dead and regularly slough away, being replaced by cells from the deeper layers (Figure 5.4).","split":"validation","source_dataset":"sciq","subject":null},{"question":"The insect reaches full size, acquires wings, and becomes sexually mature after what final stage?","choices":["larvae","metamorphosis","pupae","molt"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Body movements help circulate the hemolymph by periodically squeezing what?","choices":["the lungs","muscles","the heart","the sinuses"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the effect that causes air masses to move on a diagonal?","choices":["the coriolis effect","the headwind effect","polar effect","aurora borealis"],"answer":"A","rationale":"Why do air masses move? Winds and jet streams push them along. Cold air masses tend to move toward the Equator. Warm air masses tend to move toward the poles. The Coriolis effect causes them to move on a diagonal. Many air masses move toward the northeast over the U. S. This is the same direction that global winds blow.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Peristalsis is necessary for what basic bodily function?","choices":["reproduction","regeneration","digestion","respiration"],"answer":"C","rationale":"Describe peristalsis, and explain why it is necessary for digestion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Radioactive isotopes have the same chemical properties as stable isotopes of the same element. still, how is radioactive isotope different from stable isotopes?","choices":["they absorb light","they emit radiation","they emit magnetism","they absorb radiation"],"answer":"B","rationale":"Radioactive isotopes have the same chemical properties as stable isotopes of the same element, but they emit radiation, which can be detected. If we replace one (or more) atom(s) with radioisotope(s) in a compound, we can track them by monitoring their radioactive emissions. This type of compound is called a radioactive tracer (or radioactive label). Radioisotopes are used to follow the paths of biochemical reactions or to determine how a substance is distributed within an organism. Radioactive tracers are also used in many medical applications, including both diagnosis and treatment. They are used to measure engine wear, analyze the geological formation around oil wells, and much more. Radioisotopes have revolutionized medical practice (see Appendix M), where they are used extensively. Over 10 million nuclear medicine procedures and more than 100 million nuclear medicine tests are performed annually in the United States. Four typical examples of radioactive tracers used in medicine are technetium-99 ( 99 , thallium-201 43 Tc) , iodine-131 ( 131 , and sodium-24 ( 24 . Damaged tissues in the heart, liver, and lungs absorb certain ( 201 81 Tl) 11 Na) 53 I) compounds of technetium-99 preferentially. After it is injected, the location of the technetium compound, and hence the damaged tissue, can be determined by detecting the \u03b3 rays emitted by the Tc-99 isotope. Thallium-201 (Figure 21.24) becomes concentrated in healthy heart tissue, so the two isotopes, Tc-99 and Tl-201, are used together to study heart tissue. Iodine-131 concentrates in the thyroid gland, the liver, and some parts of the brain. It can therefore be used to monitor goiter and treat thyroid conditions, such as Grave\u2019s disease, as well as liver and brain tumors. Salt solutions containing compounds of sodium-24 are injected into the bloodstream to help locate obstructions to the flow of blood.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What can be described in terms of physical properties and chemical properties as well as its defining states?","choices":["empty space","matter","energy","mass"],"answer":"B","rationale":"Matter can be described in terms of physical properties and chemical properties.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Wetlands are extremely important as an ecosystem and as a filter for what?","choices":["clouds","storms","pollutants","wind"],"answer":"C","rationale":"Wetlands are extremely important as an ecosystem and as a filter for pollutants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Amphibians generally rely heavily on their moist skin for what with the environment?","choices":["gas exchange","cooling","sensory perception","competition"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"A change in species over time is known as?","choices":["divergence","variation","evolution","generation"],"answer":"C","rationale":"Evolution is a change in species over time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of event nearly always occurs at plate boundaries?","choices":["tsunami","eruption","hurricane","earthquake"],"answer":"D","rationale":"Scientists are not able to predict earthquakes. Since nearly all earthquakes take place at plate boundaries, scientists can predict where an earthquake will occur ( Figure below ). This information helps communities to prepare for an earthquake. For example, they can require that structures are built to be earthquake safe.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each f atom has one bonding pair and three lone pairs of what?","choices":["electrons","megatrons","ions","protons"],"answer":"A","rationale":"There are two different types of electrons in the fluorine diatomic molecule. The bonding electron pair makes the covalent bond. Each F atom has three other pairs of electrons that do not participate in the bonding; they are called lone electron pairs. Each F atom has one bonding pair and three lone pairs of electrons. Covalent bonds can be made between different elements as well. One example is HF. Each atom starts out with an odd number of electrons in its valence shell:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The embryo sac consists of only a few cells, one of which is the what?","choices":["egg","mitochondria","sperm","dna"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of organisms collect the energy from the sun and turn it into organic compounds?","choices":["microbes","autotrophs","organelles","heterotrophs"],"answer":"B","rationale":"If a plant gets hungry, it cannot walk to a local restaurant and buy a slice of pizza. So, how does a plant get the food it needs to survive? Plants are producers , which means they are able to make, or produce, their own food. They also produce the \"food\" for other organisms. Plants are also autotrophs. Autotrophs are the organisms that collect the energy from the sun and turn it into organic compounds. Using the energy from the sun, they produce complex organic compounds from simple inorganic molecules. So once again, how does a plant get the food it needs to survive?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Force is a vector because it has what two things?","choices":["space and time","size and direction","size and depth","matter and direction"],"answer":"B","rationale":"Force is a vector because it has both size and direction. Like other vectors, it can be represented by an arrow.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of rock makes up most of the earth?","choices":["Sedimentary","igneous","tuberous","Metamorphic"],"answer":"B","rationale":"Most of the Earth is made of igneous rock. The entire mantle is igneous rock, as are some areas of the crust. One of the most common igneous rocks is granite ( Figure below ). Many mountain ranges are made of granite. People use granite for countertops, buildings, monuments and statues. Pumice is also an igneous rock. Perhaps you have used a pumice stone to smooth your skin. Pumice stones are put into giant washing machines with new jeans and tumbled around. The result is stone-washed jeans!.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The seven bones of the ankle are called the what?","choices":["femurs","termals","ankular","tarsals"],"answer":"D","rationale":"The tarsals are the seven bones of the ankle. The ankle transmits the weight of the body from the tibia and the fibula to the foot. The metatarsals are the five bones of the foot. The phalanges are the 14 bones of the toes. Each toe consists of three phalanges, except for the big toe that has only two (Figure 38.15). Variations exist in other species; for example, the horse\u2019s metacarpals and metatarsals are oriented vertically and do not make contact with the substrate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for the amount of energy that is required in order to begin a chemical reaction?","choices":["conduction","function","catalytic","activation"],"answer":"D","rationale":"Although the overall process involves a release of energy (the products are lower energy than the reactants), a certain initial amount of energy needs to be present before the reaction can occur. The amount of energy required to get over the \"hump\" in the reaction diagram is referred to as the activation energy of the reaction. At the top of the peak, the reactants form what is known as an activated complex. The activated complex is the highest energy state that must be achieved in order for reactants to convert into products.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Presence or absence of what feature distinguishes vertebrates from invertebrates?","choices":["scales","backbone","hair","heart"],"answer":"B","rationale":"Animals are often identified as being either invertebrates or vertebrates. These are terms based on the skeletons of the animals. Vertebrates have a backbone made of bone or cartilage ( cartilage is a flexible supportive tissue. You have cartilage in your ear lobes. ). Invertebrates , on the other hand, have no backbone ( Figure below ). Invertebrates live just about anywhere. There are so many invertebrates on this planet that it is impossible to count them all. There are probably billions of billions of invertebrates. They come in many shapes and sizes, live practically anywhere and provide many services that are vital for the survival of other organisms, including us. They have been observed in the upper reaches of the atmosphere, in the driest of the deserts and in the canopies of the wettest rainforests. They can even be found in the frozen Antarctic or on the deepest parts of the ocean floor.","split":"validation","source_dataset":"sciq","subject":null},{"question":"All the bones of the skull, except for the mandible, are joined to each other by a fibrous joint called what?","choices":["suture","aperture","blade","stucco"],"answer":"A","rationale":"Suture All the bones of the skull, except for the mandible, are joined to each other by a fibrous joint called a suture. The fibrous connective tissue found at a suture (\u201cto bind or sew\u201d) strongly unites the adjacent skull bones and thus helps to protect the brain and form the face. In adults, the skull bones are closely opposed and fibrous connective tissue fills the narrow gap between the bones. The suture is frequently convoluted, forming a tight union that prevents most movement between the bones. (See Figure 9.5a. ) Thus, skull sutures are functionally classified as a synarthrosis, although some sutures may allow for slight movements between the cranial bones. In newborns and infants, the areas of connective tissue between the bones are much wider, especially in those areas on the top and sides of the skull that will become the sagittal, coronal, squamous, and lambdoid sutures. These broad areas of connective tissue are called fontanelles (Figure 9.6). During birth, the fontanelles provide flexibility to the skull, allowing the bones to push closer together or to overlap slightly, thus aiding movement of the infant\u2019s head through the birth canal. After birth, these expanded regions of connective tissue allow for rapid growth of the skull and enlargement of the brain. The fontanelles greatly decrease in width during the first year after birth as the skull bones enlarge. When the connective tissue between the adjacent bones is reduced to a narrow layer, these fibrous joints are now called sutures. At some sutures, the connective tissue will ossify and be converted into bone, causing the adjacent bones to fuse to each other. This fusion between bones is called a synostosis (\u201cjoined by bone\u201d). Examples of synostosis fusions between cranial bones are found both early and late in life. At the time of birth, the frontal and maxillary bones consist of right and left halves joined together by sutures, which disappear by the eighth year as the halves fuse together to form a single bone. Late in life, the sagittal, coronal, and lambdoid sutures of the skull will begin to ossify and fuse, causing the suture line to gradually disappear.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we use to keep track of electric potential energy?","choices":["wattage","amperage","voltage","temperature"],"answer":"C","rationale":"Like gravity, the electric force can do work and has a potential energy associated with it. But like we use fields to keep track of electromagnetic forces, we use electric potential , or voltage to keep track of electric potential energy. So instead of looking for the potential energy of specific objects, we define it in terms of properties of the space where the objects are.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ozone loss increases the amount of what high-energy radiation that strikes earth?","choices":["gamma rays","microwaves","infrared","ultraviolet"],"answer":"D","rationale":"Ozone loss increases the amount of high-energy ultraviolet radiation that strikes Earth. This can cause ecological and health problems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are two simple and common types of capacitor connections?","choices":["series and ionic","appearance and parallel","series and parallel","flux and parallel"],"answer":"C","rationale":"19.6 Capacitors in Series and Parallel Several capacitors may be connected together in a variety of applications. Multiple connections of capacitors act like a single equivalent capacitor. The total capacitance of this equivalent single capacitor depends both on the individual capacitors and how they are connected. There are two simple and common types of connections, called series and parallel, for which we can easily calculate the total capacitance. Certain more complicated connections can also be related to combinations of series and parallel.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the last step in scientific investigation?","choices":["data management","communication of results","document of results","migration of results"],"answer":"B","rationale":"The last step in a scientific investigation is the communication of results with others.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nematodes have an alimentary canal, but lack what?","choices":["metabolism system","nervous system","circulatory system","lymphatic system"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What instrument is used to make objects in space appear closer?","choices":["telescope","microscope","GPS","mirror"],"answer":"A","rationale":"Telescopes made objects in space seem closer. But they didn't make it any easier to visit them. Human space flight required something entirely different: rockets.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which law predicts increasing entropy based on living systems?","choices":["planetary","kinetic","kelper's","thermodynamic"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"An amine is an organic compound that can be considered to be a derivative of what?","choices":["nitrogen","calcium","ammonia","lead"],"answer":"C","rationale":"An amine is an organic compound that can be considered to be a derivative of ammonia (NH 3 ). The general structure of an amine can be abbreviated as R\u2212NH 2 , where R is a carbon chain. However, similar to alcohols, amines can be primary, secondary, or tertiary.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The hormones epinephrine and norepinephrine are associated with what rhyming mechanism?","choices":["right - or - flight","light - or- flight","fight-or-flight","bright - or - flight"],"answer":"C","rationale":"Epinephrine and Norepinephrine The catecholamines, epinephrine and NE, secreted by the adrenal medulla form one component of the extended fight-orflight mechanism. The other component is sympathetic stimulation. Epinephrine and NE have similar effects: binding to the beta-1 receptors, and opening sodium and calcium ion chemical- or ligand-gated channels. The rate of depolarization is increased by this additional influx of positively charged ions, so the threshold is reached more quickly and the period of repolarization is shortened. However, massive releases of these hormones coupled with sympathetic stimulation may actually lead to arrhythmias. There is no parasympathetic stimulation to the adrenal medulla.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Matter is composed of exceedingly small particles called what?","choices":["cells","ions","crystals","atoms"],"answer":"D","rationale":"Atomic Theory through the Nineteenth Century The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers, the scientists of their day. In the fifth century BC, Leucippus and Democritus argued that all matter was composed of small, finite particles that they called atomos, a term derived from the Greek word for \u201cindivisible. \u201d They thought of atoms as moving particles that differed in shape and size, and which could join together. Later, Aristotle and others came to the conclusion that matter consisted of various combinations of the four \u201celements\u201d\u2014fire, earth, air, and water\u2014and could be infinitely divided. Interestingly, these philosophers thought about atoms and \u201celements\u201d as philosophical concepts, but apparently never considered performing experiments to test their ideas. The Aristotelian view of the composition of matter held sway for over two thousand years, until English schoolteacher John Dalton helped to revolutionize chemistry with his hypothesis that the behavior of matter could be explained using an atomic theory. First published in 1807, many of Dalton\u2019s hypotheses about the microscopic features of matter are still valid in modern atomic theory. Here are the postulates of Dalton\u2019s atomic theory. Matter is composed of exceedingly small particles called atoms. An atom is the smallest unit of an element.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Gases have no definite shape or what?","choices":["mass","growth","smell","volume"],"answer":"D","rationale":"Gases have no definite shape or volume.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Elements have orbitals that are filled with what?","choices":["photons","electrons","ions","particles"],"answer":"B","rationale":"enters a d orbital. The valence electrons (those added after the last noble gas configuration) in these elements include the ns and (n \u2013 1) d electrons. The official IUPAC definition of transition elements specifies those with partially filled d orbitals. Thus, the elements with completely filled orbitals (Zn, Cd, Hg, as well as Cu, Ag, and Au in Figure 6.30) are not technically transition elements. However, the term is frequently used to refer to the entire d block (colored yellow in Figure 6.30), and we will adopt this usage in this textbook. Inner transition elements are metallic elements in which the last electron added occupies an f orbital. They.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Most protein antigens require signals from helper t cells (th2) to proceed to make what?","choices":["antibody","protein","bacterium","antioxidant"],"answer":"A","rationale":"B Cell Differentiation and Activation B cells differentiate in the bone marrow. During the process of maturation, up to 100 trillion different clones of B cells are generated, which is similar to the diversity of antigen receptors seen in T cells. B cell differentiation and the development of tolerance are not quite as well understood as it is in T cells. Central tolerance is the destruction or inactivation of B cells that recognize self-antigens in the bone marrow, and its role is critical and well established. In the process of clonal deletion, immature B cells that bind strongly to self-antigens expressed on tissues are signaled to commit suicide by apoptosis, removing them from the population. In the process of clonal anergy, however, B cells exposed to soluble antigen in the bone marrow are not physically deleted, but become unable to function. Another mechanism called peripheral tolerance is a direct result of T cell tolerance. In peripheral tolerance, functional, mature B cells leave the bone marrow but have yet to be exposed to self-antigen. Most protein antigens require signals from helper T cells (Th2) to proceed to make antibody. When a B cell binds to a self-antigen but receives no signals from a nearby Th2 cell to produce antibody, the cell is signaled to undergo apoptosis and is destroyed. This is yet another example of the control that T cells have over the adaptive immune response. After B cells are activated by their binding to antigen, they differentiate into plasma cells. Plasma cells often leave the secondary lymphoid organs, where the response is generated, and migrate back to the bone marrow, where the whole differentiation process started. After secreting antibodies for a specific period, they die, as most of their energy is devoted to making antibodies and not to maintaining themselves. Thus, plasma cells are said to be terminally differentiated. The final B cell of interest is the memory B cell, which results from the clonal expansion of an activated B cell. Memory B cells function in a way similar to memory T cells. They lead to a stronger and faster secondary response when compared to the primary response, as illustrated below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is caused by the buildup of stress in the rocks?","choices":["ground tilting","ground fall","debris tilting","ground dropping"],"answer":"A","rationale":"There are other possible signs before an earthquake. The ground may tilt. Ground tilting is caused by the buildup of stress in the rocks. This may happen before a large earthquake, but it doesn't always. Water levels in wells may fluctuate. This is because water may move into or out of fractures before an earthquake. This is also an uncertain way to predict an earthquake. The difference in arrival times of P-waves and S-waves may decrease just before an earthquake occurs.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Forty percent of your body mass is made up of what?","choices":["skin","cardiac muscle","skeletal muscle","blood"],"answer":"C","rationale":"Skeletal muscle is attached to bones and its contraction makes possible locomotion, facial expressions, posture, and other voluntary movements of the body. Forty percent of your body mass is made up of skeletal muscle. Skeletal muscles generate heat as a byproduct of their contraction and thus participate in thermal homeostasis. Shivering is an involuntary contraction of skeletal muscles in response to perceived lower than normal body temperature. The muscle cell, or myocyte,.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Water is composed of which two elements?","choices":["hydrogen and oxygen","oxygen and nitrogen","carbon and dioxide","hydrogen and nitrogen"],"answer":"A","rationale":"Water is a binary compound composed of hydrogen and oxygen. The hydrogen and oxygen gases produced in the reaction are both diatomic molecules.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A  polar covalent bond is a covalent bond between different atoms that attract the shared electrons by different amounts and cause an imbalance of what ?","choices":["neutron distribution","electron distribution","ions distribution","proton distribution"],"answer":"B","rationale":"EXAMPLE 13 Describe the bonding in the nitrite ion in terms of a combination of hybrid atomic orbitals and molecular orbitals. Lewis dot structures and the VSEPR model predict that the NO2\u2212 ion is bent. Given: chemical species and molecular geometry Asked for: bonding description using hybrid atomic orbitals and molecular orbitals Strategy: A Calculate the number of valence electrons in NO2\u2212. From the structure, predict the type of atomic orbital hybridization in the ion. B Predict the number and type of molecular orbitals that form during bonding. Use valence electrons to fill these orbitals and then calculate the number of electrons that remain. C If there are unhybridized orbitals, place the remaining electrons in these orbitals in order of increasing energy. Calculate the bond order and describe the bonding. Solution: A The lone pair of electrons on nitrogen and a bent structure suggest that the bonding in NO 2\u2212 is similar to the bonding in ozone. This conclusion is supported by the fact that nitrite also contains 18 valence electrons (5 from N and 6 from each O, plus 1 for the \u22121 charge). The bent structure implies that the nitrogen is sp2 hybridized. B If we assume that the oxygen atoms are sp2 hybridized as well, then we can use twosp2 hybrid orbitals on each oxygen and one sp2 hybrid orbital on nitrogen to accommodate the five lone pairs of electrons. Two sp2 hybrid orbitals on nitrogen form \u03c3 bonds with the remaining sp2 hybrid orbital on each oxygen.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two things are excess proteins converted into?","choices":["sucrose or triglycerides","glucose or triglycerides","fructose or triglycerides","glucose or sucrose"],"answer":"B","rationale":"serve as a metabolic fuel source. Proteins are not stored for later use, so excess proteins must be converted into glucose or triglycerides, and used to supply energy or build energy reserves. Although the body can synthesize proteins from amino acids, food is an important source of those amino acids, especially because humans cannot synthesize all of the 20 amino acids used to build proteins. The digestion of proteins begins in the stomach. When protein-rich foods enter the stomach, they are greeted by a mixture of the enzyme pepsin and hydrochloric acid (HCl; 0.5 percent). The latter produces an environmental pH of 1.5\u20133.5 that denatures proteins within food. Pepsin cuts proteins into smaller polypeptides and their constituent amino acids. When the food-gastric juice mixture (chyme) enters the small intestine, the pancreas releases sodium bicarbonate to neutralize the HCl. This helps to protect the lining of the intestine. The small intestine also releases digestive hormones, including secretin and CCK, which stimulate digestive processes to break down the proteins further. Secretin also stimulates the pancreas to release sodium bicarbonate. The pancreas releases most of the digestive enzymes, including the proteases trypsin, chymotrypsin, and elastase, which aid protein digestion. Together, all of these enzymes break complex proteins into smaller individual amino acids (Figure 24.17), which are then transported across the intestinal mucosa to be used to create new proteins, or to be converted into fats or acetyl CoA and used in the Krebs cycle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is an individual living creature called?","choices":["protist","species","amino","organism"],"answer":"D","rationale":"An individual living creature is called an organism . There are many characteristics that living organisms share. They all:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of a reaction if peptide bond formation?","choices":["molten synthesis reaction","recharge synthesis reaction","dehydration synthesis reaction","reversed synthesis reaction"],"answer":"C","rationale":"Figure 3.24 Peptide bond formation is a dehydration synthesis reaction. The carboxyl group of one amino acid is linked to the amino group of the incoming amino acid. In the process, a molecule of water is released.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the elements of group 17 (fluorine, chlorine, bromine, iodine, and astatine) called?","choices":["antioxidants","liquids","metals","halogens"],"answer":"D","rationale":"The elements of Group 17 (fluorine, chlorine, bromine, iodine, and astatine) are called the halogens . The halogens all have the general electron configuration n s 2 n p 5 , giving them seven valence electrons. They are one electron short of having full outer s and p sublevels, which makes them very reactive. They undergo especially vigorous reactions with the reactive alkali metals. In their pure elemental forms, chlorine and fluorine are gases at room temperature, bromine is a dark orange liquid, and iodine is a dark purple-gray solid. Astatine is so rare that its properties are mostly unknown.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for growing towards gravity?","choices":["geotropism","spirogyra","surviving","pollenation"],"answer":"A","rationale":"As you read earlier in this chapter, plant roots always grow downward because specialized cells in root caps detect and respond to gravity. This is an example of a tropism. A tropism is a turning toward or away from a stimulus in the environment. Growing toward gravity is called geotropism. Plants also exhibit phototropism, or growing toward a light source. This response is controlled by a plant growth hormone called auxin. As shown in Figure below , auxin stimulates cells on the dark side of a plant to grow longer. This causes the plant to bend toward the light.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does our solar system orbit over the course of hundreds of millions of years?","choices":["a black hole","volcanic center","retrograde center","galactic center"],"answer":"D","rationale":"Our solar system orbits the center of the galaxy as the galaxy spins. One orbit of the solar system takes about 225 to 250 million years. The solar system has orbited 20 to 25 times since it formed 4.6 billion years ago.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do inherited immunodeficiencies arise from?","choices":["viral infections","gene mutations","Allopatric speciation","stem cells"],"answer":"B","rationale":"Immunodeficiencies As you have seen, the immune system is quite complex. It has many pathways using many cell types and signals. Because it is so complex, there are many ways for it to go wrong. Inherited immunodeficiencies arise from gene mutations that affect specific components of the immune response. There are also acquired immunodeficiencies with potentially devastating effects on the immune system, such as HIV.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kinds of winds can be found in belts that span the entire circumference of the earth?","choices":["global winds","Trade winds","Periodic winds","Local Winds"],"answer":"A","rationale":"Global winds are winds that occur in belts that go all around the planet ( Figure below ). Like local winds, global winds are caused by unequal heating of the atmosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Touching, coughing, or sneezing are examples of directly spreading what microorganisms, which cause diseases like tetanus?","choices":["bacteria","pollen","algae","viruses"],"answer":"A","rationale":"You have ten times as many bacteria as human cells in your body. Most of these bacteria are harmless. However, bacteria can also cause disease. Examples of bacterial diseases include tetanus, syphilis, and food poisoning. Bacteria may spread directly from one person to another. For example, they can spread through touching, coughing, or sneezing. They may also spread via food, water, or objects.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which blood pressure is highest when the heart contracts during ventricular systole?","choices":["arterial","resting rate","systolic","diastolic"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"All the members of a species that live in the same area form a what?","choices":["habitat","population","biosphere","biome"],"answer":"B","rationale":"All the members of a species that live in the same area form a population . Many different species live together in an ecosystem. All their populations make up a community . What populations live together in the grassland pictured below ( Figure above )?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"New species may be created by natural selection and one other way. what is the other way?","choices":["artifical selection","fake selection","squalling selection","obvious selection"],"answer":"A","rationale":"Speciation, the creation of a new species, can happen through natural selection or artificial selection.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of illness is influenza?","choices":["stomach illness","mental illness","cardiac illness","respiratory illness"],"answer":"D","rationale":"Influenza, or flu, is a contagious respiratory illness caused by influenza viruses. Influenza spreads around the world in seasonal epidemics. An epidemic is an outbreak of a disease within a population of people during a specific time. Every year in the United States, about 200,000 people are hospitalized and 36,000 people die from the flu. Flu pandemics can kill millions of people. A pandemic is an epidemic that spreads through human populations across a large region (for example a continent), or even worldwide. Three influenza pandemics occurred in the 20th century and killed tens of millions of people, with each of these pandemics being caused by the appearance of a new strain of the virus. Most influenza strains can be inactivated easily by disinfectants and detergents.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In which process do paired chromosomes normally separate from each other?","choices":["diffusion","meiosis","gametes","mutations"],"answer":"B","rationale":"In the process of meiosis, paired chromosomes normally separate from each other. They end up in different gametes. Sometimes, however, errors occur. The paired chromosomes fail to separate. When this happens, some gametes get an extra copy of a chromosome. Other gametes are missing a chromosome. If one of these gametes is fertilized and survives, a chromosomal disorder results. You can see examples of such disorders in Table below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"About how many years ago did our solar system begin?","choices":["60 billion","5 billion years","3 billion","10 billion"],"answer":"B","rationale":"Our solar system began about 5 billion years ago. The Sun, planets and other solar system objects all formed at about the same time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the energy change called when a neutral atom gains an electron?","choices":["electron affinity","nuclear fission","mass affinity","fusion gain"],"answer":"A","rationale":"The energy change that occurs when a neutral atom gains an electron is called its electron affinity . When energy is released in a chemical reaction or process, that energy is expressed as a negative number. The figure below shows electron affinities in kJ\/mole for the representative elements. Electron affinities are measured on atoms in the gaseous state and are very difficult to measure accurately.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of interference characteristics does matter have compared to any wave?","choices":["one","DIfferent","when","same"],"answer":"D","rationale":"29.7 Probability: The Heisenberg Uncertainty Principle \u2022 Matter is found to have the same interference characteristics as any other wave. \u2022 There is now a probability distribution for the location of a particle rather than a definite position. \u2022 Another consequence of the wave character of all particles is the Heisenberg uncertainty principle, which limits the precision with which certain physical quantities can be known simultaneously. For position and momentum, the uncertainty principle is.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which can cause serious metabolic disorders, too little or too much thyroid hormone in the blood?","choices":["too much only","too little only","both","neither"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"How many colors of light can the human eye detect?","choices":["three","nine","infinite","six"],"answer":"A","rationale":"The human eye can detect only three colors of light. What three colors are they? How can we perceive other colors of light?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The length of a linear accelerator and the size of the d-shaped electrodes in a cyclotron severely limit the kinetic energy that particles can attain in these devices. these limitations can be overcome by using one of these?","choices":["magnet","metal","synchrotron","plastic"],"answer":"C","rationale":"To achieve the same outcome in less space, a particle accelerator called a cyclotronforces the charged particles to travel in a circular path rather than a linear one. The particles are injected into the center of a ring and accelerated by rapidly alternating the polarity of two large D-shaped electrodes above and below the ring, which accelerates the particles outward along a spiral path toward the target. The length of a linear accelerator and the size of the D-shaped electrodes in a cyclotron severely limit the kinetic energy that particles can attain in these devices. These limitations can be overcome by using a synchrotron, a hybrid of the two designs. A synchrotron contains an evacuated tube similar to that of a linear accelerator, but the tube is circular and can be more than a mile in diameter (Figure 20.10 \"A Synchrotron\"). Charged particles are accelerated around the circle by a series of magnets whose polarities rapidly alternate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The mammalian sense of touch also relies on mechanoreceptors that are the dendrites of sensory?","choices":["neurons","electrons","nerves","ions"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the largest known animal?","choices":["the blue whale","the giraffe","the elephant","the white shark"],"answer":"A","rationale":"Living things in the oceans are called marine organisms . They range from tiny bacteria to the largest known animal, the blue whale. All are adapted for life in salt water. Most are adapted for extreme pressures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Polymers can disassemble by the reverse process called what?","choices":["electrolysis","mitosis","dehydration","hydrolysis"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Purple loosestrife is a european wildflower that was introduced to which continent in the 1800's?","choices":["south america","australia","north america","asia"],"answer":"C","rationale":"Purple loosestrife is a European wildflower that was introduced to North America in the early 1800s. It soon spread to take over wetland habitats throughout the U. S. and Canada. Purple loosestrife replaces native wetland plants and threatens native wildlife by eliminating natural foods and cover. It also blocks irrigation systems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The male gametangium that produces sperm is also called what?","choices":["echinacea","trichina","xerophyte","antheridium"],"answer":"D","rationale":"Gametangia in the Seedless Plants Gametangia (singular, gametangium) are structures on the gametophytes of seedless plants in which gametes are produced by mitosis. The male gametangium, the antheridium, releases sperm. Many seedless plants produce sperm equipped with flagella that enable them to swim in a moist environment to the archegonia, the female gametangium. The embryo develops inside the archegonium as the sporophyte. Apical Meristems The shoots and roots of plants increase in length through rapid cell division within a tissue called the apical meristem (Figure 14.5). The apical meristem is a cap of cells at the shoot tip or root tip made of undifferentiated cells that continue to proliferate throughout the life of the plant. Meristematic cells give rise to all the specialized tissues of the plant. Elongation of the shoots and roots allows a plant to access additional space and resources: light in the case of the shoot, and water and minerals in the case of roots. A separate meristem, called the lateral meristem, produces cells that increase the diameter of stems and tree trunks. Apical meristems are an adaptation to allow vascular plants to grow in directions essential to their survival: upward to greater availability of sunlight, and downward into the soil to obtain water and essential minerals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part is written first when naming an ionic compound?","choices":["anion","Atom","carbonate","cation"],"answer":"D","rationale":"Ionic compounds are named by writing the name of the cation followed by the name of the anion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How does adding salt to water affect the boiling point?","choices":["reduces","maintains","increases","no difference"],"answer":"C","rationale":"Salt is often added to boiling water when preparing spaghetti or other pasta. One reason is to add flavor to the food. Some people believe that the addition of salt increases the boiling point of the water. Technically, they are correct, but the increase is rather small. You would need to add over 100 grams of NaCl to a liter of water to increase the boiling point a couple of degrees, which is just not healthy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What mineral is used in jewelry because of its striking greenish-blue color?","choices":["glass","aqua","turquoise","lime"],"answer":"C","rationale":"Diamonds have many valuable properties. Diamonds are extremely hard and are used for industrial purposes. The most valuable diamonds are large, well-shaped and sparkly. Turquoise is another mineral that is used in jewelry because of its striking greenish-blue color. Many minerals have interesting appearances. Specific terms are used to describe the appearance of minerals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ionic bonds are formed between which ions?","choices":["with random charges","with opposite charges","with the same charges","with multiple charges"],"answer":"B","rationale":"Ionic bonds are formed between ions with opposite charges. For instance, positively charged sodium ions and negatively charged chloride ions bond together to make crystals of sodium chloride, or table salt, creating a crystalline molecule with zero net charge. Certain salts are referred to in physiology as electrolytes (including sodium, potassium, and calcium), ions necessary for nerve impulse conduction, muscle contractions and water balance. Many sports drinks and dietary supplements provide these ions to replace those lost from the body via sweating during exercise.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What causes most ocean waves?","choices":["Gravity","winds","rains","tides"],"answer":"B","rationale":"Most ocean waves are caused by winds. A wave is the transfer of energy through matter. A wave that travels across miles of ocean is traveling energy, not water. Ocean waves transfer energy from wind through water. The energy of a wave may travel for thousands of miles. The water itself moves very little. Figure below shows how water molecules move when a wave goes by.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What work by lowering the activation energy of reactions and are needed to speed up chemical reactions in organisms?","choices":["enzymes","molecules","compounds","Proteins"],"answer":"A","rationale":"Enzymes are needed to speed up chemical reactions in organisms. They work by lowering the activation energy of reactions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Exon skipping is an example of what type of splicing?","choices":["proactive","comprehensive","alternative","inclusive"],"answer":"C","rationale":"One example of alternative splicing is with exon skipping. The D. melanogaster (fruit fly) doublesex (dsx) gene is involved in the fly's determination system. Pre-mRNAs from this gene contain 6 eons, numbered 1-6. In males, exons 1,2,3,5,and 6 are spliced together to form the mRNA, which encodes a transcriptional regulatory protein required for male development. In females, exons 1, 2, 3, and 4 are joined, and a polyadenylation signal in exon 4 causes cleavage of the mRNA at that point. The resulting mRNA is a transcriptional regulatory protein required for female development.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the distance between any two corresponding points on adjacent waves?","choices":["osscilation","bandwidth","wavelength","tessellation"],"answer":"C","rationale":"A wave cycle consists of one complete wave \u2013 starting at the zero point, going up to a wave crest , going back down to a wave trough , and back to the zero point again. The wavelength of a wave is the distance between any two corresponding points on adjacent waves. It is easiest to visualize the wavelength of a wave as the distance from one wave crest to the next. In an equation, wavelength is represented by the Greek letter lambda . Depending on the type of wave, wavelength can be measured in meters, centimeters, or nanometers (1 m = 10 9 nm). The frequency , represented by the Greek letter nu , is the number of waves that pass a certain point in a specified amount of time. Typically, frequency is measured in units of cycles per second or waves per second. One wave per second is also called a Hertz (Hz) and in SI units is a reciprocal second (s -1 ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Typically, what feature of an angiosperm has four main parts known as the calyx, corolla, androecium, and gynoecium?","choices":["glass","stem","leaves","flower"],"answer":"D","rationale":"Sexual Reproduction in Angiosperms The lifecycle of angiosperms follows the alternation of generations explained previously. The haploid gametophyte alternates with the diploid sporophyte during the sexual reproduction process of angiosperms. Flowers contain the plant\u2019s reproductive structures. Flower Structure A typical flower has four main parts\u2014or whorls\u2014known as the calyx, corolla, androecium, and gynoecium (Figure 32.3). The outermost whorl of the flower has green, leafy structures known as sepals. The sepals, collectively called the calyx, help to protect the unopened bud. The second whorl is comprised of petals\u2014usually, brightly colored\u2014collectively called the corolla. The number of sepals and petals varies depending on whether the plant is a monocot or dicot. In monocots, petals usually number three or multiples of three; in dicots, the number of petals is four or five, or multiples of four and five. Together, the calyx and corolla are known as the perianth. The third whorl contains the male reproductive structures and is known as the androecium. The androecium has stamens with anthers that contain the microsporangia. The innermost group of structures in the flower is the gynoecium, or the female reproductive component(s). The carpel is the individual unit of the gynoecium and has a stigma, style, and ovary. A flower may have one or multiple carpels.","split":"validation","source_dataset":"sciq","subject":null},{"question":"8each cell-surface receptor has three main components: an external ligand-binding domain, a hydrophobic membrane spanning region, and a(n) what domain inside the cell?","choices":["molecular","intracellular","inocent","isolated"],"answer":"B","rationale":"Cell-Surface Receptors Cell-surface receptors, also known as transmembrane receptors, are cell surface, membrane-anchored (integral) proteins that bind to external ligand molecules. This type of receptor spans the plasma membrane and performs signal transduction, in which an extracellular signal is converted into an intercellular signal. Ligands that interact with cell-surface receptors do not have to enter the cell that they affect. Cell-surface receptors are also called cell-specific proteins or markers because they are specific to individual cell types. Because cell-surface receptor proteins are fundamental to normal cell functioning, it should come as no surprise that a malfunction in any one of these proteins could have severe consequences. Errors in the protein structures of certain receptor molecules have been shown to play a role in hypertension (high blood pressure), asthma, heart disease, and cancer. Each cell-surface receptor has three main components: an external ligand-binding domain, a hydrophobic membranespanning region, and an intracellular domain inside the cell. The ligand-binding domain is also called the extracellular domain. The size and extent of each of these domains vary widely, depending on the type of receptor.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Special cell in the epidermis of the skin that produces the brown pigment called what?","choices":["cytoplasm","melanin","selenium","melatonin"],"answer":"B","rationale":"special cell in the epidermis of the skin that produces the brown pigment called melanin.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the most abundant source of energy found in most foods?","choices":["fats","vitamins","proteins","carbohydrates"],"answer":"D","rationale":"Carbohydrates are the most abundant source of energy found in most foods. The simplest carbohydrates, also called simple sugars, are plentiful in fruits. A monosaccharide is a carbohydrate consisting of one sugar unit. Common examples of simple sugars or monosaccharides are glucose and fructose. Both of these monosaccharides are referred to as hexoses since they have six carbons. Glucose is abundant in many plant sources and makes up sweetners such as corn sugar or grape sugar. Fructose occurs in a great many fruits and is also found in honey. These sugars are structural isomers of one another, with the difference being that glucose contains an aldehyde functional group whereas fructose contains a ketone functional group.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is considered to not be a form of precipitation?","choices":["condensation","rain","fog","snow"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Both the initiation and inhibition of cell division are triggered by events external to the cell when it is about to begin which process?","choices":["replication","mutation","isolation","extraction"],"answer":"A","rationale":"Regulation of the Cell Cycle by External Events Both the initiation and inhibition of cell division are triggered by events external to the cell when it is about to begin the replication process. An event may be as simple as the death of a nearby cell or as sweeping as the release of growthpromoting hormones, such as human growth hormone (HGH). A lack of HGH can inhibit cell division, resulting in dwarfism, whereas too much HGH can result in gigantism. Crowding of cells can also inhibit cell division. Another factor that can initiate cell division is the size of the cell; as a cell grows, it becomes inefficient due to its decreasing surface-tovolume ratio. The solution to this problem is to divide. Whatever the source of the message, the cell receives the signal, and a series of events within the cell allows it to proceed into interphase. Moving forward from this initiation point, every parameter required during each cell cycle phase must be met or the cycle cannot progress.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The binding of an antigen receptor to an epitope initiates events that activate the?","choices":["dendritic","lymphocyte","monocyte","endothelial"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Science works hand in hand with what for the advancement of both?","choices":["technology","banks","industry","government"],"answer":"A","rationale":"Although they have different goals, technology and science work hand in hand. Each helps the other advance. Scientific knowledge is needed to create new technologies. New technologies are used to further science. The microscope is a good example. Scientific knowledge of light allowed 17 th century lens makers to make the first microscopes. This new technology let scientists view a world of tiny objects they had never before seen. Figure below describes other examples.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which part of the brain is responsible for working memory?","choices":["brain stem","cerebellum","amygdala","prefrontal cortex"],"answer":"D","rationale":"14.3 Motor Responses The motor components of the somatic nervous system begin with the frontal lobe of the brain, where the prefrontal cortex is responsible for higher functions such as working memory. The integrative and associate functions of the prefrontal lobe feed into the secondary motor areas, which help plan movements. The premotor cortex and supplemental motor area then feed into the primary motor cortex that initiates movements. Large Betz cells project through the corticobulbar and corticospinal tracts to synapse on lower motor neurons in the brain stem and ventral horn of the spinal cord, respectively. These connections are responsible for generating movements of skeletal muscles. The extrapyramidal system includes projections from the brain stem and higher centers that influence movement, mostly to maintain balance and posture, as well as to maintain muscle tone. The superior colliculus and red nucleus in the midbrain, the vestibular nuclei in the medulla, and the reticular formation throughout the brain stem each have tracts projecting to the spinal cord in this system. Descending input from the secondary motor cortices, basal nuclei, and cerebellum connect to the origins of these tracts in the brain stem. All of these motor pathways project to the spinal cord to synapse with motor neurons in the ventral horn of the spinal cord. These lower motor neurons are the cells that connect to skeletal muscle and cause contractions. These neurons project through the spinal nerves to connect to the muscles at neuromuscular junctions. One motor neuron connects to multiple muscle fibers within a target muscle. The number of fibers that are innervated by a single motor neuron varies on the basis of the precision necessary for that muscle and the amount of force necessary for that motor unit. The quadriceps, for example, have many fibers controlled by single motor neurons for powerful contractions that do not need to be precise. The extraocular muscles have only a small number of fibers controlled by each motor neuron because moving the eyes does not require much force, but needs to be very precise. Reflexes are the simplest circuits within the somatic nervous system. A withdrawal reflex from a painful stimulus only requires the sensory fiber that enters the spinal cord and the motor neuron that projects to a muscle. Antagonist and postural muscles can be coordinated with the withdrawal, making the connections more complex. The simple, single neuronal.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are bundles of collecting ducts that transport urine made by nephrons to the calyces of the kidney for excretion?","choices":["cuticle","esophagus","papillae","cartoid"],"answer":"C","rationale":"Internal Anatomy A frontal section through the kidney reveals an outer region called the renal cortex and an inner region called the medulla (Figure 25.8). The renal columns are connective tissue extensions that radiate downward from the cortex through the medulla to separate the most characteristic features of the medulla, the renal pyramids and renal papillae. The papillae are bundles of collecting ducts that transport urine made by nephrons to the calyces of the kidney for excretion. The renal columns also serve to divide the kidney into 6\u20138 lobes and provide a supportive framework for vessels that enter and exit the cortex. The pyramids and renal columns taken together constitute the kidney lobes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do snakes use to smell things?","choices":["their mouth","their tongue","their nose","their eyes"],"answer":"B","rationale":"Most reptiles have good eyesight and a keen sense of smell. Snakes smell scents in the air using their forked tongue (see Figure below ). This helps them locate prey. Some snakes have heat-sensing organs on their head that help them find endothermic prey, such as small mammals and birds.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cardiac muscle normally has what kind of oxygen-using metabolism?","choices":["digestive","glucose","anarobic","aerobic"],"answer":"D","rationale":"Cardiac Muscle Metabolism Normally, cardiac muscle metabolism is entirely aerobic. Oxygen from the lungs is brought to the heart, and every other organ, attached to the hemoglobin molecules within the erythrocytes. Heart cells also store appreciable amounts of oxygen in myoglobin. Normally, these two mechanisms, circulating oxygen and oxygen attached to myoglobin, can supply sufficient oxygen to the heart, even during peak performance. Fatty acids and glucose from the circulation are broken down within the mitochondria to release energy in the form of ATP. Both fatty acid droplets and glycogen are stored within the sarcoplasm and provide additional nutrient supply. (Seek additional content for more detail about metabolism.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Burning fossil fuels releases what into the atmosphere?","choices":["carbon monoxide","phosphorus dioxide","nitrogen dioxide","carbon dioxide"],"answer":"D","rationale":"Burning organic material, such as fossil fuels, releases carbon dioxide.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cnidarians are an ancient phylum of what?","choices":["fungi","arthropods","sporozoans","eumetazoans"],"answer":"D","rationale":"33.2 Cnidarians are an ancient phylum of eumetazoans.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What theory states that both energy and matter have characteristics of waves under some conditions and characteristics of particles under other conditions?","choices":["quantum theory","atomic theory","static theory","big bang theory"],"answer":"A","rationale":"Most definitions of quantum theory and quantum mechanics offer the same description for both. These definitions essentially describe quantum theory as a theory in which both energy and matter have characteristics of waves under some conditions and characteristics of particles under other conditions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"At which location is the earth hottest?","choices":["equator","desert","meridian","seabed"],"answer":"A","rationale":"Earth is hottest at the Equator and gets cooler toward the poles. The differences in heating create huge convection currents in the troposphere. At the Equator, for example, warm air rises up to the tropopause. When it can\u2019t rise any higher, it flows north or south.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is process of producing eggs in the ovary called?","choices":["oogenesis","morphogenesis","menstruation","vaginalis"],"answer":"A","rationale":"The process of producing eggs in the ovary is called oogenesis . Eggs, like sperm, are haploid cells, and their production occurs in several steps that involve different types of cells, as shown in Figure below . You can follow the process of oogenesis in the figure as you read about it below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What protein is hair mostly made of?","choices":["Actin","keratin","Dystrophin","coronin"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is it called when the vesicle and target membrane fuse?","choices":["vesicle fusion","pathogen fusion","tendon fusion","enamel fusion"],"answer":"A","rationale":"For a vesicle to release its contents to a cell organelle or to the outside of the cell, the vesicle and target membrane must fuse. This process is called vesicle fusion. Fusion between the vesicle and a target membrane occurs in one of two ways: full fusion or \"kiss-and-run\" fusion. In a full fusion process, the vesicle phospholipids fully incorporate into the plasma membrane. The vesicle can only be reformed and by a clathrin-coat-dependent process. With kiss-and-run fusion, the vesicle reforms after the release of its material. This allows the rapid release of materials from a synaptic vesicle. In this type of fusion, the vesicle forms a fusion pore or porosome in the presynaptic membrane and releases its neurotransmitters across the synapse, after which the vesicle reforms, allowing it to be reused.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the number of covalent bonds an atom can form?","choices":["valence","atomic number","covalent number","gradient"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Momentum can be expressed as the product of mass and what else?","choices":["direction","acceleration","density","velocity"],"answer":"D","rationale":"If a bowling ball and a ping-pong ball are each moving with a velocity of 5 mph, you intuitively understand that it will require more effort to stop the bowling ball than the ping pong ball because of the greater mass of the bowling ball. Similarly, if you have two bowling balls, one moving at 5 mph and the other moving at 10 mph, you know it will take more effort to stop the ball with the greater speed. It is clear that both the mass and the velocity of a moving object contribute to what is necessary to change the motion of the moving object. The product of the mass and velocity of an object is called its momentum . Momentum is a vector quantity that has the same direction as the velocity of the object and is represented by a lowercase letter p .","split":"validation","source_dataset":"sciq","subject":null},{"question":"A carbon atom with 6 protons and 8 neutrons is more specifically known as?","choices":["carbon 6","carbon 12","carbon 14","carbon 8"],"answer":"C","rationale":"An example of a radioisotope is carbon-14. All carbon atoms have 6 protons, and most have 6 neutrons. These carbon atoms are called carbon-12, where 12 is the mass number (6 protons + 6 neutrons). A tiny percentage of carbon atoms have 8 neutrons instead of the usual 6. These atoms are called carbon-14 (6 protons + 8 neutrons). The nuclei of carbon-14 are unstable because they have too many neutrons. To be stable, a small nucleus like carbon, with just 6 protons, must have a 1:1 ratio of protons to neutrons. In other words, it must have the same number of neutrons as protons. In a large nucleus, with many protons, the ratio must be 2:1 or even 3:1 protons to neutrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Who was the first person known to use a telescope to study the sky?","choices":["Einstein","Copernicus","darwin","galileo"],"answer":"D","rationale":"Galileo was the first person known to use a telescope to study the sky. His discoveries helped change the way humans think about the universe.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of decay is electron capture a type of?","choices":["gradual decay","beta decay","alpha decay","gamma decay"],"answer":"B","rationale":"since we use the masses of neutral atoms. Electron capture is the third type of beta decay. Here, a nucleus captures an inner-shell electron and undergoes a nuclear + reaction that has the same effect as \u03b2 decay. Electron capture is sometimes denoted by the letters EC. We know that electrons cannot reside in the nucleus, but this is a nuclear reaction that consumes the electron and occurs spontaneously only when the products have less mass than the parent plus the electron. If a nuclide ZA X N is known to undergo electron capture, then its electron capture equation is A Z XN.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the result of a reaction between sulfur trioxide and water?","choices":["sulfuric acid","hydrochloric acid","acetic acid","nitric acid"],"answer":"A","rationale":"Sulfur trioxide gas reacts with water to form sulfuric acid. This is an unfortunately common reaction that occurs in the atmosphere in some places where oxides of sulfur are present as pollutants. The acid formed in the reaction falls to the ground as acid rain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Fragmentation with subsequent regeneration is a method of what, exhibited by animals such as sea stars?","choices":["bacteria reproduction","microscopic reproduction","sexual reproduction","asexual reproduction"],"answer":"D","rationale":"Watch a video (http:\/\/openstaxcollege. org\/l\/budding_hydra) of a hydra budding. Fragmentation Fragmentation is the breaking of the body into two parts with subsequent regeneration. If the animal is capable of fragmentation, and the part is big enough, a separate individual will regrow. For example, in many sea stars, asexual reproduction is accomplished by fragmentation. Figure 43.4 illustrates a sea star for which an arm of the individual is broken off and regenerates a new sea star. Fisheries workers have been known to try to kill the sea stars eating their clam or oyster beds by cutting them in half and throwing them back into the ocean. Unfortunately for the workers, the two parts can each regenerate a new half, resulting in twice as many sea stars to prey upon the oysters and clams. Fragmentation also occurs in annelid worms, turbellarians, and poriferans.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What happens to atoms during a substitution reaction?","choices":["fusion","impaction","replace another in a molecule","disintegrate"],"answer":"C","rationale":"A substitution reaction is a reaction in which one or more atoms replace another atom or group of atoms in a molecule. Alkyl halides are formed by the substitution of a halogen atom for a hydrogen atom. When methane reacts with chlorine gas, ultraviolet light can act as a catalyst for the reaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What lines the lungs and helps sweep mucus and pathogens out of the lungs?","choices":["cilia","villi","actin","alveoli"],"answer":"A","rationale":"Charles Daghlian. Cilia lining the lungs help sweep mucus and pathogens out of the lungs . Public Domain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Because most gas particles in the atmosphere are concentrated close to earth's surface, air pressure is greatest where?","choices":["at sea level","ground level","seabed floor","atmosphere"],"answer":"A","rationale":"We live in a \u201csea\u201d of air called the atmosphere. Can you feel the air in the atmosphere pressing against you? Not usually, but air actually exerts a lot of pressure because there\u2019s so much of it. The atmosphere rises high above Earth\u2019s surface, so it contains a huge number of gas particles. Most of them are concentrated close to Earth\u2019s surface because of gravity and the weight of all the air in the atmosphere above them. As a result, air pressure is greatest at sea level and drops rapidly as you go higher in altitude. The Figure below shows how air pressure falls from sea level to the top of the atmosphere. In the graph, air pressure is measured in a unit called the millibar (mb). The SI unit of pressure is newton per square centimeter (N\/cm 2 ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Control rods containing nuclides that very strongly absorb neutrons are used to adjust what?","choices":["thermal flux","fission flux","neutron flux","nuclei flux"],"answer":"C","rationale":"Control rods containing nuclides that very strongly absorb neutrons are used to adjust neutron flux. To produce large power, reactors contain hundreds to thousands of critical masses, and the chain reaction easily becomes self-sustaining, a condition called criticality. Neutron flux should be carefully regulated to avoid an exponential increase in fissions, a condition called supercriticality. Control rods help prevent overheating, perhaps even a meltdown or explosive disassembly. The water that is 235 used to thermalize neutrons, necessary to get them to induce fission in U , and achieve criticality, provides a negative.","split":"validation","source_dataset":"sciq","subject":null},{"question":"All radioactive nuclides emit high-energy particles or what?","choices":["magnetic fields","electromagnetic waves","thermal energy","isotopes"],"answer":"B","rationale":"The increased use of radioisotopes has led to increased concerns over the effects of these materials on biological systems (such as humans). All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. The most serious biological damage results when these radioactive emissions fragment or ionize molecules. For example, alpha and beta particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. When these particles strike and penetrate matter, they produce ions and molecular fragments that are extremely reactive. The damage this does to biomolecules in living organisms can cause serious malfunctions in normal cell processes, taxing the organism\u2019s repair mechanisms and possibly causing illness or even death (Figure 21.30).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What process is the synthesis of glucose from pyruvate, lactate and glycerol?","choices":["glycolysis","hydrolysis","gluconeogenesis","photosynthesis"],"answer":"C","rationale":"Gluconeogenesis is the synthesis of glucose from pyruvate, lactate, glycerol,.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the creation of a new species called?","choices":["speciation","evolution","mutation","synthesis"],"answer":"A","rationale":"The creation of a new species is called speciation . Most new species develop naturally. But humans have also artificially created new breeds and species for thousands of years.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do humans use to make observations?","choices":["senses","blood","nutrients","hormones"],"answer":"A","rationale":"Make observations. Observations refer to anything detected with one or more senses. The senses include sight, hearing, touch, smell, and taste.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The human penis contains the urethra, as well as how many cylinders of spongy erectile tissue?","choices":["three","nine","Zero","five"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"When water freezes, it expands in volume as what is formed?","choices":["movement","plasma","ice","energy"],"answer":"C","rationale":"Ice is an interesting and useful material. It can be used to cool food and keep it fresh. It can provide recreation, such as ice-skating. Ice can do great damage when it freezes \u2013 roads can buckle, houses can be damaged, water pipes can burst. All this happens because of a unique property of water and ice. When water freezes, it expands in volume as ice is formed.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a substance or object that absorbs and dissipates heat but does not experience a corresponding increase in temperature?","choices":["heat storer","heat sink","heat dispeller","heat diffuser"],"answer":"B","rationale":"Water as a Heat Sink A heat sink is a substance or object that absorbs and dissipates heat but does not experience a corresponding increase in temperature. In the body, water absorbs the heat generated by chemical reactions without greatly increasing in temperature. Moreover, when the environmental temperature soars, the water stored in the body helps keep the body cool. This cooling effect happens as warm blood from the body\u2019s core flows to the blood vessels just under the skin and is transferred to the environment. At the same time, sweat glands release warm water in sweat. As the water evaporates into the air, it carries away heat, and then the cooler blood from the periphery circulates back to the body core.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Vesicles can be classified by their contents and what else?","choices":["smell","function","color","example"],"answer":"B","rationale":"Vesicles can be classified by their contents and function.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The main function of this organ is to filter the blood and remove unwanted red blood cells?","choices":["kidney","heart","pancreas","spleen"],"answer":"D","rationale":"Organs of the lymphatic system include the tonsils, thymus gland and spleen. The thymus gland produces T cells or T-lymphocytes (see below) and the spleen and tonsils help in fighting infections. The spleen\u2019s main function is to filter the blood, removing unwanted red blood cells. The spleen also detects viruses and bacteria and triggers the release of pathogen fighting cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The brain case consists of eight bones which include the paired parietal and temporal bones, plus the unpaired frontal, occipital, sphenoid, and which other bone?","choices":["posterior","perpendicular","ethmoid","altoid"],"answer":"C","rationale":"The brain case consists of eight bones. These include the paired parietal and temporal bones, plus the unpaired frontal, occipital, sphenoid, and ethmoid bones.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What can have complex effects on soil nutrient concentrations?","choices":["sediments","prokaryotes","eukaryotes","the sun"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Rems, rads, and curies are all used to measure what?","choices":["thermal energy","gravity","potential energy","radioactivity"],"answer":"D","rationale":"Radioactivity can be expressed in a variety of units, including rems, rads, and curies.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What governs motions of stars, galaxies and other celestial objects orbiting one another?","choices":["gravitational force","electrical force","frictional force","magnetic force"],"answer":"A","rationale":"6.6 Satellites and Kepler\u2019s Laws: An Argument for Simplicity Examples of gravitational orbits abound. Hundreds of artificial satellites orbit Earth together with thousands of pieces of debris. The Moon\u2019s orbit about Earth has intrigued humans from time immemorial. The orbits of planets, asteroids, meteors, and comets about the Sun are no less interesting. If we look further, we see almost unimaginable numbers of stars, galaxies, and other celestial objects orbiting one another and interacting through gravity. All these motions are governed by gravitational force, and it is possible to describe them to various degrees of precision. Precise descriptions of complex systems must be made with large computers. However, we can describe an important class of orbits without the use of computers, and we shall find it instructive to study them. These orbits have the following characteristics: 1. A small mass.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The numbers and types of species living in what groups generally change through time, a process called ecological succession?","choices":["biospheres","regions","movements","communities"],"answer":"D","rationale":"Communities are not usually static. The numbers and types of species that live in them generally change through time. This is called ecological succession . Important cases of succession are primary and secondary succession.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Claw hammers and pulleys are examples of simple machines that do what to the direction of force applied by the user?","choices":["reverse it","nothing","neutralize it","maintain it"],"answer":"A","rationale":"Some machines change the direction of the force applied by the user. They may or may not also change the strength of the force or the distance over which it is applied. Two examples of machines that work in this way are claw hammers and the rope systems (pulleys) that raise or lower flags on flagpoles. Figure below explains how these machines work. In each case, the direction of the force applied by the user is reversed by the machine. How does this make it easier to do the job?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A circular coral reef could indicate the earlier existence of what?","choices":["avalanche","landslide","volcano","tsunami"],"answer":"C","rationale":"Reefs can form interesting shapes in the oceans. Remember that there are many volcanoes in the ocean. Coral reefs can form on volcanoes in tropical water. Since the volcanoes are cones, the reef forms in a circle around the volcano. Eventually the volcano becomes inactive. The mountain subsides and erodes so that it is below sea level. This leaves a circular coral reef ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Many fungi protect themselves from parasites and predators by producing what?","choices":["pheromes","toxic chemicals","gaseous chemicals","ammonia"],"answer":"B","rationale":"Many fungi protect themselves from parasites and predators by producing toxic chemicals. If people eat toxic fungi, they may experience digestive problems, hallucinations, organ failure, and even death. Most cases of mushroom poisoning are due to mistaken identity. That\u2019s because many toxic mushrooms look very similar to safe, edible mushrooms. An example is shown in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Acid rain falling in lakes can kill aquatic organisms by lowering what?","choices":["ph level","saliva level","color level","food level"],"answer":"A","rationale":"If acid rain falls into lakes, it lowers the pH of the water and may kill aquatic organisms. If it falls on the ground, it may damage soil and soil organisms. If it falls on plants, it may make them sick or even kill them. Acid rain also damages stone buildings, bridges, and statues, like the one in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do plant and fungi cells have that animal cells lack?","choices":["cell holes","cell walls","cell swamps","cell ridges"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which type of energy holds atoms together?","choices":["bond energy","atomic energy","curve energy","nuclear energy"],"answer":"A","rationale":"Atoms are held together by a certain amount of energy called bond energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of energy is the energy stored in an object due to its position?","choices":["mechanical energy","potential energy","directional energy","spontaneous energy"],"answer":"B","rationale":"Potential energy is the energy stored in an object due to its position. A bouncing ball at the top of a bounce, just before it starts to fall, has potential energy. For that instant, the ball is not moving, but it has the potential to move because gravity is pulling on it. Once the ball starts to fall, the potential energy changes to kinetic energy. When the ball hits the ground, it gains potential energy from the impact. The potential energy changes to kinetic energy when the ball bounces back up into the air. As the ball gains height, it regains potential energy because of gravity.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the amount of product that may be produced by a reaction under specified conditions called?","choices":["reactant","catalytic yield","theoretical yield","solute"],"answer":"C","rationale":"Percent Yield The amount of product that may be produced by a reaction under specified conditions, as calculated per the stoichiometry of an appropriate balanced chemical equation, is called the theoretical yield of the reaction. In practice, the amount of product obtained is called the actual yield, and it is often less than the theoretical yield for a number of reasons. Some reactions are inherently inefficient, being accompanied by side reactions that generate other products. Others are, by nature, incomplete (consider the partial reactions of weak acids and bases discussed earlier in this chapter). Some products are difficult to collect without some loss, and so less than perfect recovery will reduce the actual yield. The extent to which a reaction\u2019s theoretical yield is achieved is commonly expressed as its percent yield: percent yield =.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sometimes referred to as air, what do we call the mixture of gases that surrounds the planet?","choices":["galaxy","atmosphere","outer space","hemisphere"],"answer":"B","rationale":"Why is Earth the only planet in the solar system known to have life? The main reason is Earth\u2019s atmosphere. The atmosphere is a mixture of gases that surrounds the planet. We also call it air. The gases in the air include nitrogen, oxygen, and carbon dioxide. Along with water vapor, air allows life to survive. Without it, Earth would be a harsh, barren world.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is another term for seed plants?","choices":["petals","sporozoans","stems","spermatophytes"],"answer":"D","rationale":"Most vascular plants are seed plants, or spermatophytes. They reproduce with seeds and pollen.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Kinetic theory is the atomistic description of what as well as liquids and solids?","choices":["plasmas","gases","molecules","fluids"],"answer":"B","rationale":"13.4 Kinetic Theory: Atomic and Molecular Explanation of Pressure and Temperature \u2022 Kinetic theory is the atomistic description of gases as well as liquids and solids. \u2022 Kinetic theory models the properties of matter in terms of continuous random motion of atoms and molecules. \u2022 The ideal gas law can also be expressed as.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Though it can change states, and it often does, what cannot be created or destroyed?","choices":["volums","matter","mass","water content"],"answer":"B","rationale":"Then, the muscles of the uterus start contracting. The contractions get stronger and closer together. They may go on for hours. Eventually, the contractions squeeze the baby out of the uterus. Once the baby enters the vagina, the mother starts pushing. She soon pushes the baby through the vagina and out of her body.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the long carbon chains that make up lipids?","choices":["nucleic acids","proteins","fatty acids","carbohydrates"],"answer":"C","rationale":"Lipids are made up of long carbon chains called fatty acids. Like hydrocarbons, fatty acids may be saturated or unsaturated. Figure below shows structural formulas for two small fatty acids. One is saturated and one is unsaturated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"As the anterior end of the neural tube starts to develop into the brain, it undergoes a couple of enlargements; the result is the production of these?","choices":["cyclinder-like vesicles","square-like vesicles","sac-like vesicles","tributaries - like vesicles"],"answer":"C","rationale":"Primary Vesicles As the anterior end of the neural tube starts to develop into the brain, it undergoes a couple of enlargements; the result is the production of sac-like vesicles. Similar to a child\u2019s balloon animal, the long, straight neural tube begins to take on a new shape. Three vesicles form at the first stage, which are called primary vesicles. These vesicles are given names that are based on Greek words, the main root word being enkephalon, which means \u201cbrain\u201d (en- = \u201cinside\u201d; kephalon = \u201chead\u201d). The prefix to each generally corresponds to its position along the length of the developing nervous system. The prosencephalon (pros- = \u201cin front\u201d) is the forward-most vesicle, and the term can be loosely translated to mean forebrain. The mesencephalon (mes- = \u201cmiddle\u201d) is the next vesicle, which can be called the midbrain. The third vesicle at this stage is the rhombencephalon. The first part of this word is also the root of the word rhombus, which is a geometrical figure with four sides of equal length (a square is a rhombus with 90\u00b0 angles). Whereas prosencephalon and mesencephalon translate into the English words forebrain and midbrain, there is not a word for \u201cfour-sided-figure-brain. \u201d However, the third vesicle can be called the hindbrain. One way of thinking about how the brain is arranged is to use these three regions\u2014forebrain, midbrain, and hindbrain\u2014which are based on the primary vesicle stage of development (Figure 13.3a).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What makes the sun glow brightly?","choices":["nuclear fusion","ultraviolet rays","sun bursts","radiation"],"answer":"A","rationale":"What causes the sun to glow so brightly? The answer is nuclear fusion. Nuclear fusion is a type of nuclear reaction, and it releases a huge amount of energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Lens faces can generally either be concave, or what, which is the opposite of concave?","choices":["hollow","elliptical","convex","spherical"],"answer":"C","rationale":"One or both of the lens faces is part of a sphere and can be concave or convex.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Part of the fossil record, stromatolites belong to what rock group and are formed when minerals are precipitated out of water by prokaryotes in a microbial mat?","choices":["igneous","sedimentary","metamorphic","crystalline"],"answer":"B","rationale":"Stromatolites Fossilized microbial mats represent the earliest record of life on Earth. A stromatolite is a sedimentary structure formed when minerals are precipitated out of water by prokaryotes in a microbial mat (Figure 22.3). Stromatolites form layered rocks made of carbonate or silicate. Although most stromatolites are artifacts from the past, there are places on Earth where stromatolites are still forming. For example, growing stromatolites have been found in the Anza-Borrego Desert State Park in San Diego County, California.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Vinegar is an example of what type of acid?","choices":["carbonic","ascorbic","acetic","carboxylic"],"answer":"D","rationale":"Carboxylic acid is a carbonyl in which in which the carbon atom is bonded to an OH group on one side and either a carbon or hydrogen atom on the other. Carboxylic acids are weak acids, for example, vinegar.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What system of the body is most involved in the immune response?","choices":["lymphatic system","primordial system","circulatory system","anomalous system"],"answer":"A","rationale":"The immune response mainly involves the lymphatic system. The lymphatic system is a major part of the immune system. It produces leukocytes called lymphocytes. Lymphocytes are the key cells involved in the immune response. They recognize and help destroy particular pathogens in body fluids and cells. They also destroy certain cancer cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The highest level of organization in ecology is known as what?","choices":["reserves","biosphere","topmast","preserves"],"answer":"B","rationale":"The biosphere consists of all the parts of Earth where life can be found. This is the highest level of organization in ecology. It includes all of the other levels below it. The biosphere consists of all the world\u2019s biomes, both terrestrial and aquatic.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Food allergies, ulcers, and heartburn are diseases of what system of the body?","choices":["skeletal system","nervous system","circulatory system","digestive system"],"answer":"D","rationale":"Digestive system diseases include food allergies, ulcers, and heartburn.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Bases turn red litmus paper which color?","choices":["blue","white","white","pink"],"answer":"A","rationale":"Indicator compounds such as litmus can be used to detect bases. Bases turn red litmus paper blue.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two elements do ribosome consist of?","choices":["lafleur and proteins","malassezia and proteins","rrna and proteins","dna"],"answer":"C","rationale":"The ribosome consists of rRNA and proteins. It reads the sequence of codons in mRNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the flow of charge that a voltage source creates?","choices":["current","velocity","force","output"],"answer":"A","rationale":"measured at various points in a circuit, it will be seen to increase at the voltage source and decrease at the resistor. Voltage is similar to fluid pressure. The voltage source is like a pump, creating a pressure difference, causing current\u2014the flow of charge. The resistor is like a pipe that reduces pressure and limits flow because of its resistance. Conservation of energy has important consequences here. The voltage source supplies energy (causing an electric field and a current), and the resistor converts it to another form (such as thermal energy). In a simple circuit (one with a single simple resistor), the voltage supplied by the source equals the voltage drop across the resistor, since PE = q\u0394V , and the same q flows through each. Thus the energy supplied by the voltage source and the energy converted by the resistor are equal. (See Figure 20.9.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What happens to a cell's efficiency as it grows in size?","choices":["increases","multiplies","decreases","splits in half"],"answer":"C","rationale":"Small size, in general, is necessary for all cells, whether prokaryotic or eukaryotic. Let\u2019s examine why that is so. First, we\u2019ll consider the area and volume of a typical cell. Not all cells are spherical in shape, but most tend to approximate a sphere. You may remember from your high school geometry course that the formula for the surface area of a sphere is 4\u03c0r2, while the formula for its volume is 4\u03c0r3\/3. Thus, as the radius of a cell increases, its surface area increases as the square of its radius, but its volume increases as the cube of its radius (much more rapidly). Therefore, as a cell increases in size, its surface area-to-volume ratio decreases. This same principle would apply if the cell had the shape of a cube (Figure 4.7). If the cell grows too large, the plasma membrane will not have sufficient surface area to support the rate of diffusion required for the increased volume. In other words, as a cell grows, it becomes less efficient. One way to become more efficient is to divide; another way is to develop organelles that perform specific tasks. These adaptations lead to the development of more sophisticated cells called eukaryotic cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is responsible not only for cell shape changes but also for cell migration?","choices":["Golgi Apparatus","cytoskeleton","cytoplasm","cellulose"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is performed to identify disease-causing genes?","choices":["bioremediation","genetic testing","ultrasound","inoculation"],"answer":"B","rationale":"CHAPTER SUMMARY 17.1 Biotechnology Nucleic acids can be isolated from cells for the purposes of further analysis by breaking open the cells and enzymatically destroying all other major macromolecules. Fragmented or whole chromosomes can be separated on the basis of size by gel electrophoresis. Short stretches of DNA or RNA can be amplified by PCR. Southern and northern blotting can be used to detect the presence of specific short sequences in a DNA or RNA sample. The term \u201ccloning\u201d may refer to cloning small DNA fragments (molecular cloning), cloning cell populations (cellular cloning), or cloning entire organisms (reproductive cloning). Genetic testing is performed to identify disease-causing genes, and gene therapy is used to cure an inheritable disease. Transgenic organisms possess DNA from a different species, usually generated by molecular cloning techniques. Vaccines, antibiotics, and hormones are examples of products obtained by recombinant DNA technology. Transgenic plants are usually created to improve characteristics of crop plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of fossils are useful for determining the ages of rock layers?","choices":["index fossils","mold fossils","trace fossils","cast fossils"],"answer":"A","rationale":"Fossils are the best form of evidence about the history of life on Earth. Fossils also give us clues about major geological events and past climates. Index fossils are useful for determining the ages of rock layers.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of organisms carry out their life processes through division of labor and have specialized cells that do specific job?","choices":["CompoundCellular","dermal","biomolecular","multicellular"],"answer":"D","rationale":"Multicellular organisms carry out their life processes through division of labor. They have specialized cells that do specific jobs.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What defines the behavior of a compound?","choices":["size of atoms","location of atoms","group of atoms","area of atoms"],"answer":"C","rationale":"In a compound, a group of atoms that define the behavior of the compound.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What collect sunlight on the roof of a house for energy?","choices":["solar panels","clay tiles","infrared panels","asphalt shingles"],"answer":"A","rationale":"Solar panels collect sunlight on the roof of this house. The energy can be used to run the household.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The light reactions are the steps of photosynthesis that convert solar energy to what other type of energy?","choices":["chemical energy","radiation energy","carbon energy","kinetic energy"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Water waves act as a mix of longitudinal and what other kind of wave?","choices":["lateral wave","transverse wave","variable wave","latitudinal"],"answer":"B","rationale":"Water waves act as a mix of longitudinal and transverse waves. A typical water molecule pretty much moves in a circle when a wave passes through it.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for a fertilized cell that results from the uniting of two gametes?","choices":["sperm","eggs","chromosomes","zygote"],"answer":"D","rationale":"Sexual reproduction involves two parents. As you can see from Figure below , in sexual reproduction, parents produce reproductive cells\u2014called gametes \u2014that unite to form an offspring. Gametes are haploid cells. This means they contain only half the number of chromosomes found in other cells of the organism. Gametes are produced by a type of cell division called meiosis , which is described in detail in a subsequent concept. The process in which two gametes unite is called fertilization . The fertilized cell that results is referred to as a zygote . A zygote is diploid cell, which means that it has twice the number of chromosomes as a gamete.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Caffeine and alcohol are two examples of what type of drug?","choices":["nicotine","psychoactive","barbiturate","psilopsybin"],"answer":"B","rationale":"Drugs are chemicals that affect the body\u2019s structure or function. Psychoactive drugs, such as caffeine and alcohol, affect the central nervous system by influencing the transmission of nerve impulses in the brain. Psychoactive drugs may be abused and lead to drug addiction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"By maintaining a relatively constant internal environment even when the external environment changes significantly, an animal achieves what?","choices":["consciousness","homeostasis","eternal youth","hibernation"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the sticky, moist substance that covers mucous membranes called?","choices":["mucus","pus","phlegm","saliva"],"answer":"A","rationale":"One defense of mucous membranes is the mucus they release. Mucus is a sticky, moist substance that covers mucous membranes. Most pathogens get stuck in the mucus before they can do harm to the body. Many mucous membranes also have cilia. Cilia in the lungs are pictured below ( Figure below ). Cilia are tiny finger-like projections. They move in waves and sweep mucus and trapped pathogens toward body openings. When you clear your throat or blow your nose, you remove mucus and pathogens from your body.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Most receptors in the dermis are encapsulated by what?","choices":["bone tissue","connective tissue","tendons","pathogenic tissue"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The length of the route between two points is known as what?","choices":["direction","shape","velocity","distance"],"answer":"D","rationale":"Distance is the length of the route between two points.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How did seismologists originally measure the intensity of an earthquake?","choices":["regolith scale","Maxwell scale","mercalli scale","richter scale"],"answer":"C","rationale":"The ways seismologists measure an earthquake have changed over the decades. Initially, they could only measure what people felt and saw: the intensity. For this, they used the Mercalli scale.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the distance that sound waves travel in a given amount of time?","choices":["sonic speed","sound barrier","velocity of sound","speed of sound"],"answer":"D","rationale":"The speed of sound is the distance that sound waves travel in a given amount of time. You\u2019ll often see the speed of sound given as 343 meters per second. But that\u2019s just the speed of sound under a certain set of conditions, specifically, through dry air at 20 \u00b0C. The speed of sound may be very different through other matter or at other temperatures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How much of its alleles does a plant pass on when it reproduces sexually?","choices":["all","none","half","a quarter"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Using less energy or using energy more efficiently are the basic methods of what?","choices":["energy conservation","moral conservation","pressure conservation","demand conservation"],"answer":"A","rationale":"There are two basic ways to conserve energy. You can use less energy. You can also use energy more efficiently.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What will a fertilized ovule develop into?","choices":["a spore","a gonad","a spermazoa","a seed"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of particles do acids release, by definition?","choices":["hydrogen ions","fission ions","nucleic acids","quarks"],"answer":"A","rationale":"Acids are molecular compounds that release hydrogen ions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An alpha particle, which is relatively large and easily stopped by matter, is a type of what?","choices":["waste emission","plant emission","free emission","radioactive emission"],"answer":"D","rationale":"Alpha, beta, and gamma emissions have different abilities to penetrate matter. The relatively large alpha particle is easily stopped by matter (although it may impart a significant amount of energy to the matter it contacts). Beta particles penetrate slightly into matter, perhaps a few centimeters at most. Gamma rays can penetrate deeply into matter and can impart a large amount of energy into the surrounding matter. Table 11.1 \"The Three Main Forms of Radioactive Emissions\" summarizes the properties of the three main types of radioactive emissions. Table 11.1 The Three Main Forms of Radioactive Emissions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does antifreeze do to the boiling point of coolant?","choices":["raises it","accelerates it","has no effect","lowers it"],"answer":"A","rationale":"Flickr: EvelynGiggles, modified by CK-12 Foundation. Antifreeze raises the boiling point of coolant . CC BY 2.0.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are rhythmic, involuntary contractions of the reproductive structures?","choices":["sexual paroxysms","orgasm","reproductive spasms","seizure"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What happens when oppositely charged regions of neighboring water molecules are attracted to each other?","choices":["metabolic bonds form","hydrogen bonds form","potassium bonds form","oxygen is released"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when the vapor pressure of a liquid is equal to the atmospheric pressure?","choices":["melting","evaporation","freezing","boiling"],"answer":"D","rationale":"Recall that boiling occurs when the vapor pressure of a liquid is equal to the atmospheric pressure. Since adding a solute lowers the vapor pressure, we would expect a higher temperature to be required before boiling can begin. This phenomenon, known as boiling point elevation , occurs whenever a solute is dissolved into a pure solvent.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The mitotic spindle is an apparatus of microtubules that controls chromosome movement during what?","choices":["anaphase","mitosis","metaphase","prometaphase"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Pluto\u2019s orbit is in the kuiper?","choices":["field","area","zone","belt"],"answer":"D","rationale":"Pluto\u2019s orbit is in the Kuiper belt. We have discovered more than 200 million Kuiper belt objects. Pluto has 3 moons of its own. The largest, Charon, is big. Some scientists think that Pluto-Charon system is a double dwarf planet ( Figure below ). Two smaller moons, Nix and Hydra, were discovered in 2005.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does fluoride in toothpaste help prevent?","choices":["gum disease","tooth decay","plaque build up","cavities"],"answer":"B","rationale":"Figure 15.9 Fluoride, found in many toothpastes, helps prevent tooth decay (credit: Kerry Ceszyk). Unfortunately, excess fluoride can negate its advantages. Natural sources of drinking water in various parts of the world have varying concentrations of fluoride, and places where that concentration is high are prone to certain health risks when there is no other source of drinking water. The most serious side effect of excess fluoride is the bone disease, skeletal fluorosis. When excess fluoride is in the body, it can cause the joints to stiffen and the bones to thicken. It can severely impact mobility and can negatively affect the thyroid gland. Skeletal fluorosis is a condition that over 2.7 million people suffer from across the world. So while fluoride can protect our teeth from decay, the US Environmental Protection Agency sets a maximum level of 4 ppm (4 mg\/ L) of fluoride in drinking water in the US. Fluoride levels in water are not regulated in all countries, so fluorosis is a problem in areas with high levels of fluoride in the groundwater.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The mass of 1 mol of molecules in grams is numerically equivalent to the mass of how many molecules in atomic mass units?","choices":["two","ten","one","half"],"answer":"C","rationale":"The mole concept can be extended to masses of formula units and molecules as well. The mass of 1 mol of molecules (or formula units) in grams is numerically equivalent to the mass of one molecule (or formula unit) in atomic mass units. For example, a single molecule of O2 has a mass of 32.00 u, and 1 mol of O2 molecules has a mass of 32.00 g. As with atomic mass unit\u2013based masses, to obtain the mass of 1 mol of a substance, we simply sum the masses of the individual atoms in the formula of that substance. The mass of 1 mol of a substance is referred to as its molar mass, whether the substance is an element, an ionic compound, or a covalent compound.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A diagram that represents feeding relationships is also called what?","choices":["form chain","fuel chain","life chart","food chain"],"answer":"D","rationale":"Food chains and food webs are diagrams that represent feeding relationships. Essentially, they show who eats whom. In this way, they model how energy and matter move through ecosystems.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is touching a charged object to the earth called?","choices":["insulating","stabilizing","grounding","drifting"],"answer":"C","rationale":"Touching a charged object to the earth is called grounding.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Branchiopoda are mostly small, freshwater animals that feed on?","choices":["plankton and detritus","algae and plankton","fishery and detritus","nutrient and detritus"],"answer":"A","rationale":"Branchiopoda Mostly small, freshwater animals that feed on plankton and detritus. Brine shrimp.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for groups of tens to hundreds of thousands of stars?","choices":["elliptical clusters","globular clusters","constellations","nebuli"],"answer":"B","rationale":"Globular clusters ( Figure below ) are groups of tens to hundreds of thousands of stars. Gravity holds these stars tightly together. Globular clusters have a definite, spherical shape. They contain mostly old, reddish stars. Near the center of a globular cluster, the stars are closer together. The heart of the globular cluster M13 has hundreds of thousands of stars. M13 is 145 light years in diameter. The cluster contains red and blue giant stars.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Proteins may be defined as compounds of high molar mass consisting largely or entirely of chains of these?","choices":["enzymes","nucleic acids","amino acids","fatty acids"],"answer":"C","rationale":"Proteins may be defined as compounds of high molar mass consisting largely or entirely of chains of amino acids. Their masses range from several thousand to several million daltons (Da). In addition to carbon, hydrogen, and oxygen atoms, all proteins contain nitrogen and sulfur atoms, and many also contain phosphorus atoms and traces of other elements. Proteins serve a variety of roles in living organisms and are often classified by these biological roles, which are summarized in Table 18.1 \"Classification of Proteins by Biological Function\". Muscle tissue is largely protein, as are skin and hair. Proteins are present in the blood, in the brain, and even in tooth enamel. Each type of cell in our bodies makes its own specialized proteins, as well as proteins common to all or most cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Continental drift and mantle convection are supported by data originating where?","choices":["the moon","seafloor","the sun","ocean's surface"],"answer":"B","rationale":"Seafloor spreading is a mixture different ideas and data. Continental drift and mantle convection are supported by bathymetric and magnetic data from the seafloor.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Baroreceptors are specialized stretch receptors located within thin areas of blood vessels and heart chambers that respond to the degree of stretch caused by the presence of this?","choices":["bile","water","bacteria","blood"],"answer":"D","rationale":"Baroreceptor Reflexes Baroreceptors are specialized stretch receptors located within thin areas of blood vessels and heart chambers that respond to the degree of stretch caused by the presence of blood. They send impulses to the cardiovascular center to regulate blood pressure. Vascular baroreceptors are found primarily in sinuses (small cavities) within the aorta and carotid arteries: The aortic sinuses are found in the walls of the ascending aorta just superior to the aortic valve, whereas the carotid sinuses are in the base of the internal carotid arteries. There are also low-pressure baroreceptors located in the walls of the venae cavae and right atrium. When blood pressure increases, the baroreceptors are stretched more tightly and initiate action potentials at a higher rate. At lower blood pressures, the degree of stretch is lower and the rate of firing is slower. When the cardiovascular center in the medulla oblongata receives this input, it triggers a reflex that maintains homeostasis (Figure 20.18): \u2022 When blood pressure rises too high, the baroreceptors fire at a higher rate and trigger parasympathetic stimulation of the heart. As a result, cardiac output falls. Sympathetic stimulation of the peripheral arterioles will also decrease, resulting in vasodilation. Combined, these activities cause blood pressure to fall. \u2022 When blood pressure drops too low, the rate of baroreceptor firing decreases. This will trigger an increase in sympathetic stimulation of the heart, causing cardiac output to increase. It will also trigger sympathetic stimulation of the peripheral vessels, resulting in vasoconstriction. Combined, these activities cause blood pressure to rise.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What structure forms a barrier between the cytoplasm and the environment outside the cell?","choices":["cell membrane","Cytoskeleton","Flippases","Lipid bilayer"],"answer":"A","rationale":"The cell membrane is like the bag holding the Jell-O. It encloses the cytoplasm of the cell. It forms a barrier between the cytoplasm and the environment outside the cell. The function of the cell membrane is to protect and support the cell. It also controls what enters or leaves the cell. It allows only certain substances to pass through. It keeps other substances inside or outside the cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are waxes made up of?","choices":["long - chain pyroclastic acids","long-chain natural acids","long-chain fatty acids","long - project fatty acids"],"answer":"C","rationale":"Another category of lipid molecule is waxes. Waxes are esters of long-chain fatty acids and long-chain alcohols. Waxes are soft solids with generally low melting points and are insoluble in water. The Figure below shows the structure of cetyl palmitate, a natural wax present in sperm whales.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The biggest drawback of what type of reproduction is lack of genetic variation, since all offspring are identical?","choices":["sexual reproduction","organic reproduction","asexual reproduction","meiosis"],"answer":"C","rationale":"In asexual reproduction, all the offspring are exactly the same. This is the biggest drawback of this type of reproduction. Why? Lack of genetic variation increases the risk of extinction. Without variety, there may be no organisms that can survive a major change in the environment.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name given to the daily wake\/sleep cycle?","choices":["circadian rhythms","variable rhythms","nocturnal rhythms","behavioral rhythms"],"answer":"A","rationale":"Daily cycles of behavior, including sleeping a waking, are called circadian rhythms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where is the seafloor youngest?","choices":["deep currents","sand bars","mid-ocean","inland"],"answer":"C","rationale":"Seafloor is youngest near the mid-ocean ridges and gets progressively older with distance from the ridge. Orange areas show the youngest seafloor. The oldest seafloor is near the edges of continents or deep sea trenches.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the interaction of waves with other waves?","choices":["wave interference","tsunami","shockwave","current"],"answer":"A","rationale":"Wave interference is the interaction of waves with other waves.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Filter feeders called rotifers collect digestive and excretory wastes in what primitive organ?","choices":["simple stomach","bile duct","liver","cloacal bladder"],"answer":"D","rationale":"The rotifers are filter feeders that will eat dead material, algae, and other microscopic living organisms, and are therefore very important components of aquatic food webs. Rotifers obtain food that is directed toward the mouth by the current created from the movement of the corona. The food particles enter the mouth and travel to the mastax (pharynx with jawlike structures). Food then passes by digestive and salivary glands, and into the stomach, then onto the intestines. Digestive and excretory wastes are collected in a cloacal bladder before being released out the anus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What mass of abnormal cells do cancer cells cause?","choices":["bacteria","inflammation","sebaceous cyst","tumor"],"answer":"D","rationale":"Cancer cells grow rapidly and may form a mass of abnormal cells called a tumor.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ultraviolet light has higher frequencies and shorter wavelengths than visible light, which means it has more what?","choices":["energy","width","length","pressure"],"answer":"A","rationale":"Ultraviolet light has shorter wavelengths and higher frequencies than visible light. Ultraviolet light also has more energy, which makes it useful for killing germs. Too much exposure to ultraviolet light can damage the skin.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What planet has a surface temperature of over 400 degrees celsius, no oxygen, an atomsphere comprised mainly of carbon dioxide and tremendous atmospheric pressure?","choices":["venus","Earth","uranus","Mars"],"answer":"A","rationale":"The atmosphere of Venus is markedly different from that of Earth. The gases in the Venusian atmosphere are 96.5% carbon dioxide and 3% nitrogen. The atmospheric pressure on Venus is roughly 92 times that of Earth, so the amount of nitrogen on Venus would contribute a pressure well over 2700 mm Hg. And there is no oxygen present, so we couldn\u2019t breathe there. Not that we would want to go to Venus \u2013 the surface temperature is usually over 460\u00b0C.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which is the body system that normally fights infections and defends against other causes of disease?","choices":["immune system","reproductive system","circulatory system","infectious system"],"answer":"A","rationale":"The immune system is the body system that normally fights infections and defends against other causes of disease. When the immune system is working well, it usually keeps you from getting sick. But like any other body system, the immune system can have problems and develop diseases. Two types of immune system diseases are autoimmune diseases and allergies.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is used to calculate ejection fraction?","choices":["svs","cns","umts","rws"],"answer":"A","rationale":"SVs are also used to calculate ejection fraction, which is the portion of the blood that is pumped or ejected from the heart with each contraction. To calculate ejection fraction, SV is divided by EDV. Despite the name, the ejection fraction is normally expressed as a percentage. Ejection fractions range from approximately 55\u201370 percent, with a mean of 58 percent.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How does a sexually transmitted infection spread?","choices":["sexual contact","linear contact","dramatic contact","enviromental contact"],"answer":"A","rationale":"A sexually transmitted infection (STI) is an infection that spreads through sexual contact. STIs are caused by pathogens , a living thing or virus that causes infection. The pathogens enter the body through the reproductive organs. Many STIs also spread through body fluids, such as blood. For example, a shared tattoo needle is one way an STI could spread. Some STIs can also spread from a mother to her baby during childbirth.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Stem cells are unspecialized cells that can reproduce themselves via cell division, sometimes after years of inactivity. under certain conditions, they may differentiate into tissue-specific or organ-specific cells with special these?","choices":["mutations","functions","chromosomes","enzymes"],"answer":"B","rationale":"Stem Cells and Repair of Kidney Damage Stem cells are unspecialized cells that can reproduce themselves via cell division, sometimes after years of inactivity. Under certain conditions, they may differentiate into tissue-specific or organ-specific cells with special functions. In some cases, stem cells may continually divide to produce a mature cell and to replace themselves. Stem cell therapy has an enormous potential to improve the quality of life or save the lives of people suffering from debilitating or lifethreatening diseases. There have been several studies in animals, but since stem cell therapy is still in its infancy, there have been limited experiments in humans. Acute kidney injury can be caused by a number of factors, including transplants and other surgeries. It affects 7\u201310 percent of all hospitalized patients, resulting in the deaths of 35\u201340 percent of inpatients. In limited studies using mesenchymal stem cells, there have been fewer instances of kidney damage after surgery, the length of hospital stays has been reduced, and there have been fewer readmissions after release. How do these stem cells work to protect or repair the kidney? Scientists are unsure at this point, but some evidence has shown that these stem cells release several growth factors in endocrine and paracrine ways. As further studies are conducted to assess the safety and effectiveness of stem cell therapy, we will move closer to a day when kidney injury is rare, and curative treatments are routine.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process of soil dissolving in rain called?","choices":["migration","sedimentation","abrasion","erosion"],"answer":"D","rationale":"Mechanical weathering increases the rate of chemical weathering. As rock breaks into smaller pieces, the surface area of the pieces increases. With more surfaces exposed, there are more places for chemical weathering to occur. Let\u2019s say you wanted to make some hot chocolate on a cold day. It would be hard to get a big chunk of chocolate to dissolve in your milk or hot water. Maybe you could make hot chocolate from some smaller pieces like chocolate chips, but it is much easier to add a powder to your milk. This is because the smaller the pieces are, the more surface area they have. Smaller pieces dissolve more easily.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are all living things on earth formed of?","choices":["dioxide compounds","iron compounds","carbon compounds","hydrogen compounds"],"answer":"C","rationale":"Introduction All living things on earth are formed mostly of carbon compounds. The prevalence of carbon compounds in living things has led to the epithet \u201ccarbon-based\u201d life. The truth is we know of no other kind of life. Early chemists regarded substances isolated from organisms (plants and animals) as a different type of matter that could not be synthesized artificially, and these substances were thus known as organic compounds. The widespread belief called vitalism held that organic compounds were formed by a vital force present only in living organisms. The German chemist Friedrich Wohler was one of the early chemists to refute this aspect of vitalism, when, in 1828, he reported the synthesis of urea, a component of many body fluids, from nonliving materials. Since then, it has been recognized that organic molecules obey the same natural laws as inorganic substances, and the category of organic compounds has evolved to include both natural and synthetic compounds that contain carbon. Some carbon-containing compounds are not classified as organic, for example, carbonates and cyanides, and simple oxides, such as CO and CO2. Although a single, precise definition has yet to be identified by the chemistry community, most agree that a defining trait of organic molecules is the presence of carbon as the principal element, bonded to hydrogen and other carbon atoms. Today, organic compounds are key components of plastics, soaps, perfumes, sweeteners, fabrics, pharmaceuticals, and many other substances that we use every day. The value to us of organic compounds ensures that organic chemistry is an important discipline within the general field of chemistry. In this chapter, we discuss why the element carbon gives rise to a vast number and variety of compounds, how those compounds are classified, and the role of organic compounds in representative biological and industrial settings.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is another name for critical speed?","choices":["normal speed","terminal speed","gravity","impossible velocity"],"answer":"B","rationale":"accelerate indefinitely (as it would if we neglect air resistance, for example). Instead, viscous drag increases, slowing acceleration, until a critical speed, called the terminal speed, is reached and the acceleration of the object becomes zero. Once this happens, the object continues to fall at constant speed (the terminal speed). This is the case for particles of sand falling in the ocean, cells falling in a centrifuge, and sky divers falling through the air. Figure 12.19 shows some of the factors that affect terminal speed. There is a viscous drag on the object that depends on the viscosity of the fluid and the size of the object. But there is also a buoyant force that depends on the density of the object relative to the fluid. Terminal speed will be greatest for low-viscosity fluids and objects with high densities and small sizes. Thus a skydiver falls more slowly with outspread limbs than when they are in a pike position\u2014head first with hands at their side and legs together. Take-Home Experiment: Don\u2019t Lose Your Marbles By measuring the terminal speed of a slowly moving sphere in a viscous fluid, one can find the viscosity of that fluid (at that temperature). It can be difficult to find small ball bearings around the house, but a small marble will do. Gather two or three fluids (syrup, motor oil, honey, olive oil, etc. ) and a thick, tall clear glass or vase. Drop the marble into the center of the fluid and time its fall (after letting it drop a little to reach its terminal speed). Compare your values for the terminal speed and see if they are inversely proportional to the viscosities as listed in Table 12.1. Does it make a difference if the marble is dropped near the side of the glass? Knowledge of terminal speed is useful for estimating sedimentation rates of small particles. We know from watching mud settle out of dirty water that sedimentation is usually a slow process. Centrifuges are used to speed sedimentation by creating accelerated frames in which gravitational acceleration is replaced by centripetal acceleration, which can be much greater, increasing the terminal speed.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Prokaryotes are much simpler than what in many of their features?","choices":["eukaryotes","membranes","meteorites","microorganisms"],"answer":"A","rationale":"14.2 DNA Structure and Sequencing The currently accepted model of the double-helix structure of DNA was proposed by Watson and Crick. Some of the salient features are that the two strands that make up the double helix are complementary and anti-parallel in nature. Deoxyribose sugars and phosphates form the backbone of the structure, and the nitrogenous bases are stacked inside. The diameter of the double helix, 2 nm, is uniform throughout. A purine always pairs with a pyrimidine; A pairs with T, and G pairs with C. One turn of the helix has ten base pairs. During cell division, each daughter cell receives a copy of the DNA by a process known as DNA replication. Prokaryotes are much simpler than eukaryotes in many of their features. Most prokaryotes contain a single, circular chromosome. In general, eukaryotic chromosomes contain a linear DNA molecule packaged into nucleosomes, and have two distinct regions that can be distinguished by staining, reflecting different states of packaging and compaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which two atoms are found in most organic compounds?","choices":["potassium and carbon","hydrogen and magnesium","magnesium and carbon","hydrogen and carbon"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"How are heat changes in chemical reactions measured?","choices":["watts","velocities","amperes","joules"],"answer":"D","rationale":"Heat changes in chemical reactions are typically measured in joules rather than calories. The conversion between a joule and a calorie is shown below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a genetic disorder in which blood fails to clot properly because a normal clotting factor in the blood is lacking?","choices":["hemophilia","anemia","sickle cell","hypertension"],"answer":"A","rationale":"Hemophilia is a genetic disorder in which blood fails to clot properly because a normal clotting factor in the blood is lacking. In people with hemophilia, even a minor injury can cause a life-threatening loss of blood. Most cases of hemophilia are caused by a recessive gene on the X chromosome. The disorder is expressed much more commonly in males because they have just one X chromosome.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Fungi that reproduce sexually create what?","choices":["a chromoplast","a sperm cell","an ova","a zygospore"],"answer":"D","rationale":"Fungi can reproduce sexually to create a zygospore.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A long strip of sand is referred to as what?","choices":["a composition island","a component island","a barrier island","a volcano"],"answer":"C","rationale":"A barrier island is a long strip of sand. The sand naturally moves in the local currents. People try to build on barrier islands.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which viruses are being studied for cancer treatments?","choices":["osteophobic viruses","astringent viruses","endophytic viruses","oncolytic viruses"],"answer":"D","rationale":"Viruses that infect cancer cells are being studied for their use in cancer treatments. Oncolytic viruses are viruses that lyse and kill cancer cells. Some researchers are hoping to treat some cancers with these viruses.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Mercury looks a lot like earth's moon. why do you think it does? both have been struck by a lot of what?","choices":["floods","asteroids","particles","waves"],"answer":"B","rationale":"Mercury looks a lot like Earth's Moon. Why do you think it does? Both have been struck by a lot of asteroids. Both have no atmosphere, so there is no weathering and erosion. If they had an atmosphere, many of the craters would have been eroded away. Both have no plate tectonics to transform the landscape. This would also remove a lot of craters.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the smallest particle of an element that still has the properties of that element?","choices":["electron","nucleus","neutron","atom"],"answer":"D","rationale":"The smallest particle of an element that still has the properties of that element is the atom. All the atoms of an element are like one another, and are different from the atoms of all other elements.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the three-dimensional structure of a single polypeptide called?","choices":["Cysteine structure","tertiary structure","immature structure","immature Structure"],"answer":"B","rationale":"Tertiary structure refers to the three-dimensional structure of a single polypeptide. The alpha-helices and beta-sheets are folded into a compact globule structure. Stability is maintained through hydrogen bonds, disulfide bonds and other interactions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term is used to descibe the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration?","choices":["diffusion","convection","permeation","radiation"],"answer":"A","rationale":"Diffusion is the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration. For cell transport, diffusion is the movement of small molecules across the cell membrane. The difference in the concentrations of the molecules in the two areas is called the concentration gradient . The kinetic energy of the molecules results in random motion, causing diffusion. In simple diffusion, this process proceeds without the aid of a transport protein. it is the random motion of the molecules that causes them to move from an area of high concentration to an area with a lower concentration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A source of what is needed to disturb matter and start a mechanical wave?","choices":["hydrogen","respiration","magnetism","energy"],"answer":"D","rationale":"The waves in the picture above are examples of mechanical waves. A mechanical wave is a disturbance in matter that transfers energy through the matter. A mechanical wave starts when matter is disturbed. A source of energy is needed to disturb matter and start a mechanical wave.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Much of the damage from hurricanes may be caused by?","choices":["wind chill","insurance fraud","hail","storm surge"],"answer":"D","rationale":"A hurricane is a large storm with high winds and heavy rains. Hurricanes develop from tropical cyclones. They form over warm ocean water. Much of the damage from hurricanes may be caused by storm surge.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Color blindness, hemophilia and muscular dystrophy are three x-linked what?","choices":["genes","alleles","phenotypes","chromosomes"],"answer":"C","rationale":"Color blindness, hemophilia and muscular dystrophy are three x-linked phenotypes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An apocrine sweat gland is usually associated with hair follicles in densely hairy areas, such as armpits and genital regions. apocrine sweat glands are larger than eccrine sweat glands and lie deeper in the dermis, sometimes even reaching this?","choices":["papillary dermis","stratum corneum","hypodermis","epidermis"],"answer":"C","rationale":"An apocrine sweat gland is usually associated with hair follicles in densely hairy areas, such as armpits and genital regions. Apocrine sweat glands are larger than eccrine sweat glands and lie deeper in the dermis, sometimes even reaching the hypodermis, with the duct normally emptying into the hair follicle. In addition to water and salts, apocrine sweat includes organic compounds that make the sweat thicker and subject to bacterial decomposition and subsequent smell. The release of this sweat is under both nervous and hormonal control, and plays a role in the poorly understood human pheromone response. Most commercial antiperspirants use an aluminum-based compound as their primary active ingredient to stop sweat. When the antiperspirant enters the sweat gland duct, the aluminum-based compounds precipitate due to a change in pH and form a physical block in the duct, which prevents sweat from coming out of the pore.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the only way to transfer thermal energy without matter?","choices":["ultraviolet light","radiation","evaporation","osmosis"],"answer":"B","rationale":"Thermal radiation is one of three ways that thermal energy can be transferred. The other two ways are conduction and convection, both of which need matter to transfer energy. Radiation is the only way of transferring thermal energy that doesn\u2019t require matter. To learn more about thermal radiation, watch \u201cRadiation\u201d at the URL below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When plants are shut off from environmental cues they become?","choices":["synchronized","desynchronized","extinct","pollinated"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of vertebrates integrates the endocrine and nervous systems?","choices":["the notochord","the hypothalamus","the cerebellum","the forebrain"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"An individual grows quickly and develops new abilities during infancy and?","choices":["embryonic stage","childhood","senior years","adulthood"],"answer":"B","rationale":"An individual grows quickly and develops new abilities during infancy and childhood.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Prokaryotes are unicellular organisms that lack organelles surrounded by what?","choices":["tissues","cells","particles","membranes"],"answer":"D","rationale":"The Prokaryotic Cell Recall that prokaryotes (Figure 13.5) are unicellular organisms that lack organelles surrounded by membranes. Therefore, they do not have a nucleus but instead have a single chromosome\u2014a piece of circular DNA located in an area of the cell called the nucleoid. Most prokaryotes have a cell wall lying outside the plasma membrane. The composition of the cell wall differs significantly between the domains Bacteria and Archaea (and their cell walls also differ from the eukaryotic cell walls found in plants and fungi. ) The cell wall functions as a protective layer and is responsible for the organism\u2019s shape. Some other structures are present in some prokaryotic species, but not in others. For example, the capsule found in some species enables the organism to attach to surfaces and protects it from dehydration. Some species may also have flagella (singular, flagellum) used for locomotion, and pili (singular, pilus) used for attachment to surfaces and to other bacteria for conjugation. Plasmids, which consist of small, circular pieces of DNA outside of the main chromosome, are also present in many species of bacteria.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of a plant is the food making factory?","choices":["the growing tips","the leaves","the main stem","the roots"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of molecules do hydrogen bonds hold together?","choices":["air","gas","carbon","water"],"answer":"D","rationale":"Hydrogen bonds hold adjacent water molecules together.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The greenhouse effect is associated with what negative phenomenon, blamed mainly on human activity?","choices":["advanced warming","resulting warming","cool warming","global warming"],"answer":"D","rationale":"Recent global warming is due mainly to human actions. Burning fossil fuels adds carbon dioxide to the atmosphere. Carbon dioxide is a greenhouse gas. It\u2019s one of several that human activities add to the atmosphere. An increase in greenhouse gases leads to greater greenhouse effect. The result is increased global warming. Figure below shows the increase in carbon dioxide since 1960.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What \"color\" (that is actually not a color at all) is associated with the absence of light?","choices":["clear","black","grey","opaque"],"answer":"B","rationale":"The color of light that strikes an object may also affect the color that the object appears. For example, if only blue light strikes a red apple, the blue light is absorbed and no light is reflected. When no light reflects from an object, it looks black. Black isn\u2019t a color. It is the absence of light.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What science is the study of matter and how it behaves?","choices":["chemistry","geneology","geology","biology"],"answer":"A","rationale":"Chemistry is the study of matter and how it behaves.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we call the study of life and living things?","choices":["physics","engineering","life science","chemistry"],"answer":"C","rationale":"Life science is the study of life and living things. Living things are also called organisms . Life science is often referred to as biology. Life scientists work in many different settings, from classrooms to labs to natural habitats. Dr. Katherine Smith, who is pictured in Figure below is a life scientist who works for NOAA (National Oceanic and Atmospheric Administration). She studies freshwater shrimp and fish in their natural habitats.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The average global temperature has been rising since the end of what era?","choices":["miocene","pleistocene","flintstone","glacial"],"answer":"B","rationale":"The average global temperature has been rising since the end of the Pleistocene. With some ups and downs, of course. Rising temperatures are natural for this time period. But natural causes cannot explain all the warming that's been happening. There is some other factor at work.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are animals that eat a prey animal?","choices":["scavengers","herbivores","carnivores","predators"],"answer":"D","rationale":"Predators are animals that eat a prey animal. Scavengers eat organisms that are already dead. Decomposers break down dead plants and animals into component parts, including nutrients.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the only decomposers that can break down tough plant substances, including lignin and cellulose?","choices":["insects","fungi","flatworms","bacteria"],"answer":"B","rationale":"Bacteria are also major decomposers, but they can grow and feed only on the exposed surfaces of organic matter. In contrast, fungi can use their hyphae to penetrate deep into organic matter. Fungi are also the only decomposers that can break down tough plant substances, including lignin (in wood) and cellulose (in plant cell walls). They have special enzymes to do this work. The enzymes are released by the tips of the hyphae. Because of these abilities, fungi are the primary decomposers in forests (see Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of carbon compound is methane?","choices":["alternating compounds","dynamic organic compounds","stable compounds","volatile organic compounds"],"answer":"D","rationale":"Volatile organic compounds (VOCs) are carbon compounds, such as methane. VOCs are released by many human activities. Raising livestock, for example, produces a lot of methane.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In diffusion, substances tend to move from an area of high concentration to an area of what kind of concentration?","choices":["low","rise","Increase","drop"],"answer":"A","rationale":"Diffusion Diffusion is a passive process of transport. A single substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across a space. You are familiar with diffusion of substances through the air. For example, think about someone opening a bottle of ammonia in a room filled with people. The ammonia gas is at its highest concentration in the bottle; its lowest concentration is at the edges of the room. The ammonia vapor will diffuse, or spread away, from the bottle, and gradually, more and more people will smell the ammonia as it spreads. Materials move within the cell\u2019s cytosol by diffusion, and certain materials move through the plasma membrane by diffusion (Figure 5.8). Diffusion expends no energy. On the contrary, concentration gradients are a form of potential energy, dissipated as the gradient is eliminated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In what kind of state are particles fixed in place relative to one another?","choices":["hybrid state","solid state","liquid state","useful state"],"answer":"B","rationale":"In the solid state, particles are fixed in place relative to one another. In the liquid and gas states, individual particles are free to move.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is defined as the amount of energy needed to increase the temperature of one gram of water by 1\u00b0c. one calorie equals 4.184 joules?","choices":["calorie","fat","sulfur","weight"],"answer":"A","rationale":"A related unit is the calorie. This term arose prior to the establishment of the SI system and is now replaced by the joule in most situations. One calorie is defined as the amount of energy needed to increase the temperature of one gram of water by 1\u00b0C. One calorie equals 4.184 joules. Note that this calorie is not exactly the same as the calories listed on food products. One food Calorie (usually written with a capital C) is equal to 1000 \u201cregular\u201d calories. Thus, a 140-Calorie snack can be fully digested to produce 140,000 calories of energy. We will use the SI unit joules in our discussions of heat energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"About a third of all bacteria in the gut are members of what species?","choices":["bacteroides","trematodes","actinomyces","spirochetes"],"answer":"A","rationale":"A wide range of friendly bacteria live in the gut. Bacteria begin to populate the human digestive system right after birth. Gut bacteria include Lactobacillus , the bacteria commonly used in probiotic foods such as yogurt, and E. coli bacteria. About a third of all bacteria in the gut are members of the Bacteroides species. Bacteroides are key in helping us digest plant food.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What form of feedback occurs when an accumulation of an end product slows the process that makes that product?","choices":["optimal feedback","positive feedback","negative feedback","particular feedback"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for a disease in which the immune system makes an inflammatory response to a harmless antigen?","choices":["nausea","influenza","allergy","diabetes"],"answer":"C","rationale":"An allergy is a disease in which the immune system makes an inflammatory response to a harmless antigen. Any antigen that causes an allergy is called an allergen. Allergens may be inhaled or ingested, or they may come into contact with the skin. Two common causes of allergies are shown in Figure below . Inhaling ragweed pollen may cause coughing and sneezing. Skin contact with oils in poison ivy may cause an itchy rash.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why is it easier to move boxes on a wheeled dolly than by sliding them?","choices":["starting friction","increase surface tension","more total work","rolling friction"],"answer":"D","rationale":"Rolling friction is friction that acts on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why it is much easier to move boxes on a wheeled dolly than by carrying or sliding them. It also explains why most forms of ground transportation use wheels, including cars, 4-wheelers, bicycles, roller skates, and skateboards. Ball bearings are another use of rolling friction (see Figure below ). They allow parts of a wheel or other machine to roll rather than slide over one another.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the protein in red blood cells that transports oxygen in the bloodstream?","choices":["hemoglobin","plasma","insulin","rH factor"],"answer":"A","rationale":"Hemoglobin is a protein in red blood cells that transports oxygen in the bloodstream. Scientists studied hemoglobin simply to learn how it worked. Out of this research came an understanding of how the protein changes shape when oxygen attaches to it. This information was then applied to help patients with sickle cell anemia, a disorder caused by an abnormal hemoglobin structure that makes hemoglobin molecules clump up when oxygen leaves the protein. Basic knowledge of protein structure led to an improved understanding of a wide-spread disease and opened the door for development of treatments.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Space shuttles are reusable vehicles designed to get astronauts where?","choices":["underwater","distant solar systems","space","the 6th dimension"],"answer":"C","rationale":"Space shuttles are reusable vehicles for American astronauts to get into space.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Specialized peroxisomes called glyoxysomes are found in the fat-storing tissues of what?","choices":["plant seeds","plant leaves","chloroplasts","plant stems"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The nervous system, together with what system, controls all the other organ systems?","choices":["reproductive system","skeletal system","endocrine system","limb system"],"answer":"C","rationale":"The nervous system, together with the endocrine system, controls all the other organ systems. The nervous system sends one type of signal around the body, and the endocrine system sends another type of signal around the body. The endocrine system makes and releases chemical messenger molecules, or hormones, which tell other body parts that a change or a reaction is necessary. So what type of signal does the nervous system send?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the physical breakdown of chunks of food into smaller pieces?","choices":["dissolving","mechanical digestion","mechanical accumulation","mechanical catalyst"],"answer":"B","rationale":"Mechanical digestion is the physical breakdown of chunks of food into smaller pieces. This type of digestion takes place mainly in the mouth and stomach.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Technically, which cells are the only autotrophic parts of the plant?","choices":["brown","red","yellow","green"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"This is the study of evolutionary history of groups of related organisms?","choices":["paleontology","phylogeny","synonymy","phrenology"],"answer":"B","rationale":"Phylogeny is the evolutionary history of group of related organisms. It is represented by a phylogenetic tree that shows how species are related to each other through common ancestors. A clade is a group of organisms that includes an ancestor and all of its descendants. It is a phylogenetic classification, based on evolutionary relationships.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does urine leave the body through?","choices":["the skin","the vagina","the urethra","the intestine"],"answer":"C","rationale":"process in which urine leaves the body through a sphincter at the end of the urethra.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What phase is pure chlorine present as?","choices":["mist","oil\/gas","gas","liquid"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"When electrons from two atoms are each attracted to the nucleus of the other atom, what type of bond is formed?","choices":["electrochemical bond","hydrogen bond","covalent bond","ionic bond"],"answer":"C","rationale":"Covalent bonds form when the electron clouds of two atoms overlap with each other. In a simple H 2 molecule, the single electron in each atom becomes attracted to the nucleus of the other atom in the molecule as the atoms come closer together. Other covalent bonds form in the same way as unpaired electrons from two atoms \u201cmatch up\u201d to form the bond. In a fluorine atom, there is an unpaired electron in one of the 2p orbitals. When a F 2 molecule forms, the 2p orbitals from each of the two atoms overlap to produce the F\u2212F covalent bond. The overlapping orbitals do not have to be of the same type to form a covalent bond. For example, in a molecule of HF, the 1s orbital of the hydrogen atom overlaps with the 2p orbital of the fluorine atom ( Figure below ):.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Wave cut platforms are level areas formed by what?","choices":["wave erosion","surge erosion","glaciers","shock erosion"],"answer":"A","rationale":"Wave-cut platforms are level areas formed by wave erosion. Since these platforms are above sea level, it means that either sea level was higher relative or the rock was lower.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Electronegativities are used to determine the polarity of covalent bonds. the polarity of a covalent bond can be judged by determining the difference of the electronegativities of what involved in the covalent bond?","choices":["three atoms","six atoms","two atoms","seven atoms"],"answer":"C","rationale":"Electronegativities are used to determine the polarity of covalent bonds. The polarity of a covalent bond can be judged by determining the difference of the electronegativities of the two atoms involved in the covalent bond, as summarized in the following table: Electronegativity Difference.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the cell walls of fungi made of?","choices":["casein","proteins","lectin","chitin"],"answer":"D","rationale":"The cell walls of fungi are made of chitin. Chitin is a tough carbohydrate that also makes up the outer skeleton of insects. The cell walls of plants are made of cellulose.","split":"validation","source_dataset":"sciq","subject":null},{"question":"All the water in the open ocean is referred to as what zone, which is further divided by depth?","choices":["oceanic","pelagic","terrestrial","aquatic"],"answer":"B","rationale":"Other ocean zones are farther from shore in the open ocean. All the water in the open ocean is called the pelagic zone. It is further divided by depth:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How many embryonic cell layers do flatworms have?","choices":["five","four","three","two"],"answer":"C","rationale":"Flatworms have three embryonic cell layers. They have a mesoderm layer in addition to ectoderm and endoderm layers. The mesoderm layer allows flatworms to develop muscle tissues so they can move easily over solid surfaces.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When gasoline is burned, what pollutant is produced?","choices":["fluorocarbons","carbon dioxide","oxygen","methane"],"answer":"B","rationale":"Using gasoline to power automobiles affects the environment. The exhaust fumes from burning gasoline cause air pollution. These pollutants include smog and ground-level ozone. Air pollution is a big problem for cities where large numbers of people drive every day. Burning gasoline also produces carbon dioxide. This is a greenhouse gas and is a cause of global warming. Similar pollutants come from other forms of oil.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kingdom of organisms is characterized by having sensory organs, movement, and internal digestion?","choices":["bacteria","animals","plants","fungi"],"answer":"B","rationale":"Animals not only have specialized cells. Most animals also have tissues and organs. In many animals, organs form organ systems, such as a nervous system. Higher levels of organization allow animals to perform many complex functions. What can animals do that most other living things cannot? Most animals share these characteristics: sensory organs , movement , and internal digestion . All of them are illustrated in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the base numbering system of metric units?","choices":["sixes","tens","twos","ones"],"answer":"B","rationale":"Metric units use a base numbering system of 10. Thus a centimeter is ten times larger than a millimeter. A decimeter is 10 times larger than a centimeter and a meter is 10 times larger than a decimeter. Thus a meter is 100 times larger than a centimeter and 1000 times larger than a millimeter. Going the other way, one can say that there are 100 cm contained in a meter.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do fungi lack which makes it impossible for them to use photosynthesis?","choices":["ammonia","roots","sodium","chlorophyll"],"answer":"D","rationale":"Fungi lack chlorophyll, so they cannot make food by photosynthesis as plants can. Instead, they are heterotrophs, like animals. But they don\u2019t have a mouth or teeth. So how do fungi \u201ceat\u201d? They get their nutrition by absorbing organic compounds from other organisms. The other organisms may be dead or alive, depending on the fungus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Spicules are most conspicuously present in which class?","choices":["hexactinellida","spirogyra","phylum","trichina"],"answer":"A","rationale":"Take an up-close tour (http:\/\/openstaxcollege. org\/l\/sponge_ride) through the sponge and its cells. The presence and composition of spicules\/spongin are the differentiating characteristics of the three classes of sponges (Figure 28.4): Class Calcarea contains calcium carbonate spicules and no spongin, class Hexactinellida contains six-rayed siliceous spicules and no spongin, and class Demospongia contains spongin and may or may not have spicules; if present, those spicules are siliceous. Spicules are most conspicuously present in class Hexactinellida, the order consisting of glass sponges. Some of the spicules may attain giant proportions (in relation to the typical size range of glass sponges of 3 to 10 mm) as seen in Monorhaphis chuni, which grows up to 3 m long.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Most of the food that they bring to their chicks is very rich in what?","choices":["lipids","glucose","grains","proteins"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Two plates may slide past each other in opposite directions, this is called what?","choices":["shearing plate boundary","downstream plate boundary","transform plate boundary","earthquake"],"answer":"C","rationale":"Two plates may slide past each other in opposite directions. This is called a transform plate boundary. These plate boundaries experience massive earthquakes. The world\u2019s best known transform fault is the San Andreas Fault in California ( Figure below ). At this fault, the Pacific and North American plates grind past each other. Transform plate boundaries are most common as offsets along mid-ocean ridges.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term is used to describe elements with unstable nuclei?","choices":["explosive","waste","radioactive","larvae"],"answer":"C","rationale":"Gamma rays are produced when radioactive elements decay. Radioactive elements are elements with unstable nuclei. To become more stable, the nuclei undergo radioactive decay. In this process, the nuclei give off energy and may also emit charged particles of matter. Types of radioactive decay include alpha, beta, and gamma decay. In alpha and beta decay, both particles and energy are emitted. In gamma decay , only energy, in the form of gamma rays, is emitted.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the third gene of lac operon in addition to lacz and lacy?","choices":["laca","leya","Lacy","ghara"],"answer":"A","rationale":"The three genes of the lac operon are lacZ, lacY, and lacA. They encode proteins needed to digest lactose. The genes are expressed only in the presence of lactose.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The majority of species in the phylum chordata are found in what subphylum, which includes animals ranging from lampreys to mammals?","choices":["vertebrates","lophotrochozoa","organelles","tardigrada"],"answer":"A","rationale":"Chordates The majority of species in the phylum Chordata are found in the subphylum Vertebrata, which include many species with which we are familiar. The vertebrates contain more than 60,000 described species, divided into major groupings of the lampreys, fishes, amphibians, reptiles, birds, and mammals. Animals in the phylum Chordata share four key features that appear at some stage of their development: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail (Figure 15.33). In certain groups, some of these traits are present only during embryonic development. The chordates are named for the notochord, which is a flexible, rod-shaped structure that is found in the embryonic stage of all chordates and in the adult stage of some chordate species. It is located between the digestive tube and the nerve cord, and provides skeletal support through the length of the body. In some chordates, the notochord acts as the primary axial support of the body throughout the animal\u2019s lifetime. In vertebrates, the notochord is present during embryonic development, at which time it induces the development of the neural tube and serves as a support for the developing embryonic body. The notochord, however, is not found in the postnatal stage of vertebrates; at this point, it has been replaced by the vertebral column (the spine). The dorsal hollow nerve cord is derived from ectoderm that sinks below the surface of the skin and rolls into a hollow tube during development. In chordates, it is located dorsally to the notochord. In contrast, other animal phyla possess solid nerve cords that are located either ventrally or laterally. The nerve cord found in most chordate embryos develops into the brain and spinal cord, which compose the central nervous system. Pharyngeal slits are openings in the pharynx, the region just posterior to the mouth, that extend to the outside environment. In organisms that live in aquatic environments, pharyngeal slits allow for the exit of water that enters the mouth during feeding. Some invertebrate chordates use the pharyngeal slits to filter food from the water that enters the mouth. In fishes, the pharyngeal slits are modified into gill supports, and in jawed fishes, jaw supports. In tetrapods, the slits are further modified into components of the ear and tonsils, since there is no longer any need for gill supports in these air-breathing.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why is having grasping hands and feet important for primates?","choices":["hang on trees","protecting habitat","foraging for food","migrating"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The rising and sinking of warm and cooler material is called what?","choices":["convection","depression","insulation","diffusion"],"answer":"A","rationale":"Hot lower mantle material rises upwards ( Figure below ). As it rises, it cools. At the top of the mantle it moves horizontally. Over time it becomes cool and dense enough that it sinks. Back at the bottom of the mantle, it travels horizontally. Eventually the material gets to the location where warm mantle material is rising. The rising and sinking of warm and cooler material is convection. The motion described creates a convection cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the remarkable ring of light around the sun called?","choices":["laguna","panorama","corona","magnetic halo"],"answer":"C","rationale":"A solar eclipse is kind of like a field trip to the Sun from Earth. You can see something (with special tinted glasses) that you don't usually see. The Sun has a remarkable ring of light around it. This is the corona. If you have a chance to see a solar eclipse, you should do it.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Particles in what state of matter do not experience any force of mutual attraction or repulsion?","choices":["solid","plasma","gas","liquid"],"answer":"C","rationale":"Gas particles do not experience any force of attraction or repulsion with each other.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a type of plant tissue consisting of undifferentiated cells that can continue to divide and differentiate?","choices":["ganglion","meristem","tuber","malignant"],"answer":"B","rationale":"The key to continued growth and repair of plant cells is meristem . Meristem is a type of plant tissue consisting of undifferentiated cells that can continue to divide and differentiate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are basic tools of the cell for organizing metabolism, transport, and storage of molecules?","choices":["vesicles","membranes","tissues","vacuoles"],"answer":"A","rationale":"A vesicle is a small, spherical compartment that is separated from the cytosol by at least one lipid bilayer. Many vesicles are made in the Golgi apparatus and the endoplasmic reticulum, or are made from parts of the cell membrane. Vesicles from the Golgi apparatus can be seen in Figure above . Because it is separated from the cytosol, the space inside the vesicle can be made to be chemically different from the cytosol. Vesicles are basic tools of the cell for organizing metabolism, transport, and storage of molecules. Vesicles are also used as chemical reaction chambers. They can be classified by their contents and function.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The ileum is the last part of what organ, and is where the bile salts and vitamins are absorbed into blood stream?","choices":["stomach","gall bladder","large intestine","small intestine"],"answer":"D","rationale":"The ileum, also illustrated in Figure 34.11 is the last part of the small intestine and here the bile salts and vitamins are absorbed into blood stream. The undigested food is sent to the colon from the ileum via peristaltic movements of the muscle. The ileum ends and the large intestine begins at the ileocecal valve. The vermiform, \u201cworm-like,\u201d appendix is located at the ileocecal valve. The appendix of humans secretes no enzymes and has an insignificant role in immunity. Large Intestine The large intestine, illustrated in Figure 34.13, reabsorbs the water from the undigested food material and processes the waste material. The human large intestine is much smaller in length compared to the small intestine but larger in diameter. It has three parts: the cecum, the colon, and the rectum. The cecum joins the ileum to the colon and is the receiving pouch for the waste matter. The colon is home to many bacteria or \u201cintestinal flora\u201d that aid in the digestive processes. The colon can be divided into four regions, the ascending colon, the transverse colon, the descending colon and the sigmoid colon. The main functions of the colon are to extract the water and mineral salts from undigested food, and to store waste material. Carnivorous mammals have a shorter large intestine compared to herbivorous mammals due to their diet.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Total internal reflections the princicple behind what type of optics?","choices":["fiber optics","Blindness","refined optics","pipes optics"],"answer":"A","rationale":"Total internal reflection is the principle behind fiber optics . A bundle of fibers made out of glass or plastic only a few micrometers in diameter is called a light pipe since light can be transmitted along it with almost no loss. Light passing down the fibers makes glancing collisions with the walls so that total internal reflection occurs.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which cells at the base of the hair root form the outer root sheath?","choices":["basal","scala media","tunnel fibers","scala vestibuli"],"answer":"A","rationale":"Figure 5.12 Hair Follicle The slide shows a cross-section of a hair follicle. Basal cells of the hair matrix in the center differentiate into cells of the inner root sheath. Basal cells at the base of the hair root form the outer root sheath. LM \u00d7 4. (credit: modification of work by \u201ckilbad\u201d\/Wikimedia Commons).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for sediment deposited by a glacier?","choices":["plateau","moraine","holocene","crater"],"answer":"B","rationale":"Moraine is sediment deposited by a glacier. A ground moraine is a thick layer of sediments left behind by a retreating glacier. An end moraine is a low ridge of sediments deposited at the end of the glacier. It marks the greatest distance the glacier advanced.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Usually done on computers, what do you call sets of equations that take into account many factors to represent a phenomenon?","choices":["mathematical models","fractals","spreadsheets","analogous models"],"answer":"A","rationale":"Mathematical models are sets of equations that take into account many factors to represent a phenomenon. Mathematical models are usually done on computers.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the mode of breathing that occurs at rest and does not require the cognitive thought of the individual?","choices":["forced breathing","quiet breathing","small breathing","conscious breathing"],"answer":"B","rationale":"There are different types, or modes, of breathing that require a slightly different process to allow inspiration and expiration. Quiet breathing, also known as eupnea, is a mode of breathing that occurs at rest and does not require the cognitive thought of the individual. During quiet breathing, the diaphragm and external intercostals must contract. A deep breath, called diaphragmatic breathing, requires the diaphragm to contract. As the diaphragm relaxes, air passively leaves the lungs. A shallow breath, called costal breathing, requires contraction of the intercostal muscles. As the intercostal muscles relax, air passively leaves the lungs. In contrast, forced breathing, also known as hyperpnea, is a mode of breathing that can occur during exercise or actions that require the active manipulation of breathing, such as singing. During forced breathing, inspiration and expiration both occur due to muscle contractions. In addition to the contraction of the diaphragm and intercostal muscles, other accessory muscles must also contract. During forced inspiration, muscles of the neck, including the scalenes, contract and lift the thoracic wall, increasing lung volume. During forced expiration, accessory muscles of the abdomen, including the obliques, contract, forcing abdominal organs upward against the diaphragm. This helps to push the diaphragm further into the thorax, pushing more air out. In addition, accessory muscles (primarily the internal intercostals) help to compress the rib cage, which also reduces the volume of the thoracic cavity.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Rubber is what kind of solid?","choices":["amorphous","aqueous","porous","inorganic"],"answer":"A","rationale":"When a tire goes flat, its shape changes. The tire might be flat because of a slow leak in the tire valve. It could be flat because it ran over a nail or screw and ended up with a small hole where the air can leak out over a period of time. Or it could go flat when it hits a large rock or other object while travelling at high speeds (this one is for those readers who enjoy detective movies or TV shows). What if a crystalline solid like LiBr were ever made into a tire (now there\u2019s a weird idea)? When it encountered a blow, the crystal would break into small pieces. Since rubber is an amorphous solid, it has a very different set of physical properties.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do birds do in mating season?","choices":["find many mates","migrate","pair up with the same bird","reproduce asexually"],"answer":"C","rationale":"Yes. Birds do actually pair up each mating season, if not for life. And the male better be prepared to treat his female properly. There is actually an elaborate process in which the female chooses her mate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What exciting and evolving field of physics finds that nature on the smallest scale may have its greatest influence on the large-scale character of the universe?","choices":["proteins physics","particle physics","biophysics","astrophysics"],"answer":"B","rationale":"This chapter covers the basics of particle physics as we know it today. An amazing convergence of topics is evolving in particle physics. We find that some particles are intimately related to forces, and that nature on the smallest scale may have its greatest influence on the large-scale character of the universe. It is an adventure exceeding the best science fiction because it is not only fantastic, it is real.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In genetics, what does it mean when the amount is longer since the amount of time since a species diverged?","choices":["greater differences in dna","greater making in dna","Less difference in DNA","tilt differences in dna"],"answer":"A","rationale":"Scientists can compare the DNA or proteins of different species. If the molecules are similar, this shows that the species are related. The more similar the molecules are, the closer the relationship is likely to be. When molecules are used in this way, they are called molecular clocks . This method assumes that random mutations occur at a constant rate for a given protein or segment of DNA. Over time, the mutations add up. The longer the amount of time since species diverged, the more differences there will be in their DNA or proteins.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ragweed and poison ivy are common causes of what?","choices":["mutations","allergies","cancers","defects"],"answer":"B","rationale":"Ragweed and poison ivy are common causes of allergies. Are you allergic to these plants?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of distance is caused by the force you apply to a machine over a given distance?","choices":["accumulation distance","response distance","input distance","force distance"],"answer":"C","rationale":"The force you apply to a machine is applied over a given distance, called the input distance. The force applied by the machine to the object is also applied over a distance, called the output distance. The output distance may or may not be the same as the input distance.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is calculated by dividing the mass by the volume of a certain object?","choices":["density","radius","median","diameter"],"answer":"A","rationale":"The density of a certain object is calculated by dividing the mass by the volume. Suppose that a mass of 37.46 g is divided by a volume of 12.7 cm 3 . The result on a calculator would be:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Electric motors transform electrical energy into what other form of energy?","choices":["thermal","solar","kinetic","magnetic"],"answer":"C","rationale":"An electric motor is a device that uses an electromagnet to change electrical energy to kinetic energy. Figure below shows a simple diagram of an electric motor. The motor contains an electromagnet that is connected to a shaft. When current flows through the motor, the electromagnet turns, causing the shaft to turn as well. The rotating shaft moves other parts of the device.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The bicoid maternal effect gene is transcribed in which cells of the mother?","choices":["cell walls","nurse cells","boy cells","veteran cells"],"answer":"B","rationale":"The bicoid maternal effect gene is transcribed in the nurse cells of the mother and then the mRNA is transferred to the oocyte. Mutant embryos from homozygous mutant bicoid mothers fail to produce head and thorax structures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How often an allele occurs in a gene pool relative to the other alleles for that gene is known as _______","choices":["genomic frequency","allele frequency","genetic rate","allele succession"],"answer":"B","rationale":"Allele frequency is how often an allele occurs in a gene pool relative to the other alleles for that gene. Look at the example in Table below . The population in the table has 100 members. In a sexually reproducing species, each member of the population has two copies of each gene. Therefore, the total number of copies of each gene in the gene pool is 200. The gene in the example exists in the gene pool in two forms, alleles A and a . Knowing the genotypes of each population member, we can count the number of alleles of each type in the gene pool. The table shows how this is done.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If more coils are added to an electromagnet it becomes?","choices":["brighter","stronger","lighter","weaker"],"answer":"B","rationale":"The combined magnetic force of the magnetized wire coil and iron bar makes an electromagnet very strong. In fact, electromagnets are the strongest magnets made. An electromagnet is stronger if there are more turns in the coil of wire or there is more current flowing through it. A bigger bar or one made of material that is easier to magnetize also increases an electromagnet\u2019s strength. At the following URL, you can see an animation demonstrating how these factors affect the strength of an electromagnet. http:\/\/www. schoolphysics. co. uk\/animations\/Electromagnet\/index. html.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which trait of particles causes even cold objects to have some thermal energy?","choices":["momentum","equilibrium","constant random motion","kinetic energy"],"answer":"C","rationale":"Scientists think that multicellularity arose from cooperation between many organisms of the same species. The Colonial Theory proposes that this cooperation led to the development of a multicellular organism. Many examples of cooperation between organisms in nature have been observed. For example, a certain species of amoeba (a single-celled protist) groups together during times of food shortage and forms a colony that moves as one to a new location. Some of these amoebas then become slightly differentiated from each other. Volvox, shown in Figure above , is another example of a colonial organism. Most scientists accept that the Colonial theory explains how multicellular organisms evolved.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Found in many electric devices, what is a coil of wire wrapped around a bar of iron or other ferromagnetic material?","choices":["superconductor","battery","actuator","electromagnet"],"answer":"D","rationale":"The animal mole is very different than the counting unit of the mole. Chemists nonetheless have adopted the mole as their unofficial mascot. National Mole Day is a celebration of chemistry that occurs on October 23rd (10\/23) of each year.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is it called when two organisms live close together and form a relationship?","choices":["definitions","traits","Family","symbiosis"],"answer":"D","rationale":"Fungi don't live in isolation. They often interact with other species. In fact, fungi can be dependent on another organism for survival. When two species live close together and form a relationship, it is called symbiosis . Symbiosis can be beneficial to one or both organisms, or sometimes one organism hurts the other. Some of the partners in these relationships include plants, algae, insects and other animals, and even humans.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does fsh help stimulate in the ovaries and sperm in the testes?","choices":["dna replication","spawning","in vitro fertilization","maturation of eggs"],"answer":"D","rationale":"Peptide and Protein Hormones Whereas the amine hormones are derived from a single amino acid, peptide and protein hormones consist of multiple amino acids that link to form an amino acid chain. Peptide hormones consist of short chains of amino acids, whereas protein hormones are longer polypeptides. Both types are synthesized like other body proteins: DNA is transcribed into mRNA, which is translated into an amino acid chain. Examples of peptide hormones include antidiuretic hormone (ADH), a pituitary hormone important in fluid balance, and atrial-natriuretic peptide, which is produced by the heart and helps to decrease blood pressure. Some examples of protein hormones include growth hormone, which is produced by the pituitary gland, and follicle-stimulating hormone (FSH), which has an attached carbohydrate group and is thus classified as a glycoprotein. FSH helps stimulate the maturation of eggs in the ovaries and sperm in the testes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The largest phylum of the animal kingdom is what?","choices":["crustaceans","mammals","arthropods","cephalopods"],"answer":"C","rationale":"Arthropods are not only the largest phylum of invertebrates. They are by far the largest phylum of the animal kingdom. Roughly 80 percent of all animal species living on Earth today are arthropods. Obviously, arthropods have been extremely successful. What accounts for their success?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"During what process is light from the star focused and the star appears to brighten in a characteristic manner?","choices":["excitation","spectrometry","microlensing","macrolensing"],"answer":"C","rationale":"In a process called microlensing, light from the star is focused and the star appears to brighten in a characteristic manner. Searches for dark matter in this form are particularly interested in galactic halos because of the huge amount of mass that seems to be there. Such microlensing objects are thus called massive compact halo objects, or MACHOs. To date, a few MACHOs have been observed, but not predominantly in galactic halos, nor in the numbers needed to explain dark matter. MACHOs are among the most conventional of unseen objects proposed to explain dark matter. Others being actively pursued are red dwarfs, which are small dim stars, but too few have been seen so far, even with the Hubble Telescope, to be of significance. Old remnants of stars called white dwarfs are also under consideration, since they contain about a solar mass, but are small as the Earth and may dim to the point that we ordinarily do not observe them. While white dwarfs are known, old dim ones are not. Yet another possibility is the existence of large numbers of smaller than stellar mass black holes left from the Big Bang\u2014here evidence is entirely absent. There is a very real possibility that dark matter is composed of the known neutrinos, which may have small, but finite, masses. As discussed earlier, neutrinos are thought to be massless, but we only have upper limits on their masses, rather than knowing they are exactly zero. So far, these upper limits come from difficult measurements of total energy emitted in the decays and reactions in which neutrinos are involved. There is an amusing possibility of proving that neutrinos have mass in a completely different way. We have noted in Particles, Patterns, and Conservation Laws that there are three flavors of neutrinos ( \u03bd e ,.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Much like the processes of dna replication and transcription, translation consists of three main stages: initiation, elongation, and this?","choices":["detonation","assimilation","termination","isolation"],"answer":"C","rationale":"Much like the processes of DNA replication and transcription, translation consists of three main stages: initiation, elongation, and termination. Initiation takes place with the binding of a ribosome to an mRNA transcript. The elongation stage involves the recognition of a tRNA anticodon with the next mRNA codon in the sequence. Once the anticodon and codon sequences are bound (remember, they are complementary base pairs), the tRNA presents its amino acid cargo and the growing polypeptide strand is attached to this next amino acid. This attachment takes place with the assistance of various enzymes and requires energy. The tRNA molecule then releases the mRNA strand, the mRNA strand shifts one codon over in the ribosome, and the next appropriate tRNA arrives with its matching anticodon. This process continues until the final codon on the mRNA is reached which provides a \u201cstop\u201d message that signals termination of translation and triggers the release of the complete, newly synthesized protein. Thus, a gene within the DNA molecule is transcribed into mRNA, which is then translated into a protein product (Figure 3.29).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each hemisphere of the cerebrum consists of four parts, called what?","choices":["quarters","lobes","rows","layers"],"answer":"B","rationale":"Each hemisphere of the cerebrum consists of four parts, called lobes. Each lobe is associated with particular brain functions. Just one function of each lobe is listed here.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is an organic compound that is the primary component of natural gas?","choices":["ethanol","magnesium","methane","sulfur"],"answer":"C","rationale":"Methane is an organic compound that is the primary component of natural gas. Its structure consists of a central carbon atom with four single bonds to hydrogen atoms (see Figure below ). In order to maximize their distance from one another, the four groups of bonding electrons do not lie in the same plane. Instead, each of the hydrogen atoms lies at the corners of a geometrical shape called a tetrahedron. The carbon atom is at the center of the tetrahedron. Each face of a tetrahedron is an equilateral triangle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is raising the temperature of earth\u2019s surface?","choices":["photosynthesis effect","ozone layer","Coriolis effect","greenhouse effect"],"answer":"D","rationale":"Gases such as carbon dioxide from the burning of fossil fuels increase the natural greenhouse effect. This is raising the temperature of Earth\u2019s surface, and is called global warming.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a measure of randomness or disorder in a system?","choices":["chaos theory","biodiversity","enthropy","entropy"],"answer":"D","rationale":"Figure 6.12 Entropy is a measure of randomness or disorder in a system. Gases have higher entropy than liquids, and liquids have higher entropy than solids.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the distance between two corresponding points of adjacent waves called?","choices":["bandwidth","variation","wavelength","wave distance"],"answer":"C","rationale":"Wave amplitude is the maximum distance the particles of a medium move from their resting positions as a wave passes through. Wavelength is the distance between two corresponding points of adjacent waves. Waves with greater amplitudes or shorter wavelengths have more energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Crossing-over is the exchange of genetic material between which chromosomes?","choices":["metacentric","homologous","analogous","monogamous"],"answer":"B","rationale":"When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a ridge of sand that extends away from the shore?","choices":["a scoop","a spit","a depression","a dig"],"answer":"B","rationale":"A spit is a ridge of sand that extends away from the shore. The end of the spit may hook around toward the quieter waters close to shore.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Manganin is made up of metals that include copper, manganese and nickel - what do you generally call a metal of this type?","choices":["complex metal","alloy","silicon","mixed metal"],"answer":"B","rationale":"for metals, meaning their resistivity increases with temperature. Some alloys have been developed specifically to have a small temperature dependence. Manganin (which is made of copper, manganese and nickel), for example, has \u03b1 close to zero (to three digits on the scale in Table 20.2), and so its resistivity varies only slightly with temperature. This is useful for making a temperature-independent resistance standard, for example.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Protons and neutrons are located in which central part of the atom?","choices":["radius","nucleolus","shell","nucleus"],"answer":"D","rationale":"Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu) . One atomic mass unit equals the mass of a proton, which is about 1.7 \u00d7 10 -24 g. Each neutron also has a mass of 1 amu. Therefore, the sum of the protons and neutrons in an atom is about equal to the atom\u2019s total mass in atomic mass units.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate this?","choices":["cell cycle","digestion","blood flow","respiration"],"answer":"A","rationale":"10.4 Cancer and the Cell Cycle Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate the cell cycle. The loss of control begins with a change in the DNA sequence of a gene that codes for one of the regulatory molecules. Faulty instructions lead to a protein that does not function as it should. Any disruption of the monitoring system can allow other mistakes to be passed on to the daughter cells. Each successive cell division will give rise to daughter cells with even more accumulated damage. Eventually, all checkpoints become nonfunctional, and rapidly reproducing cells crowd out normal cells, resulting in a tumor or leukemia (blood cancer).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Slabs of continents moving around on earth's surface is called what?","choices":["fault tectonics","crator tectonics","edge tectonics","plate tectonics"],"answer":"D","rationale":"Plate tectonics theory says that slabs of continents move around on Earth's surface. The mechanism for that movement is seafloor spreading. Plate tectonics explain many things about Earth: (1) geological activity, why it happens where it does; (2) natural resources, why many are found where they are; and (3) the past and future, what happened in the past and what will happen in the future. The theory of plate tectonics will be explored in the chapter Plate Tectonics .","split":"validation","source_dataset":"sciq","subject":null},{"question":"In plants, what structure located above the root cap is where growth in length occurs?","choices":["secondary meristem","elections meristem","support meristem","primary meristem"],"answer":"D","rationale":"As shown in Figure below , the tip of a root is called the root cap. It consists of specialized cells that help regulate primary growth of the root at the tip. Above the root cap is primary meristem, where growth in length occurs.","split":"validation","source_dataset":"sciq","subject":null},{"question":"With what does an electromagnetic wave start?","choices":["static charged particle","vibrating charged particle","battery","kinetic energy"],"answer":"B","rationale":"An electromagnetic wave starts with a vibrating charged particle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of overdose do eudicots die from?","choices":["chemical","nutritional","hormonal","metabolic"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The particles in a colloid are large enough to scatter light, a phenomenon called what?","choices":["bowman effect","tyndall effect","jonah effect","astral effect"],"answer":"B","rationale":"The particles in a colloid are large enough to scatter light, a phenomenon called the Tyndall effect. This can make colloidal mixtures appear cloudy or opaque, such as the searchlight beams shown in Figure 11.31. Clouds are colloidal mixtures. They are composed of water droplets that are much larger than molecules, but that are small enough that they do not settle out.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two things limit primary production in aquatic ecosystems?","choices":["light and nutrients","air and light","air and nutrients","pollution and nutrients"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Vascular and non-vascular are two groups of what kind of organism?","choices":["fungi","animals","vertebrates","plants"],"answer":"D","rationale":"The Major Divisions of Land Plants The green algae and land plants are grouped together into a subphylum called the Streptophytina, and thus are called Streptophytes. In a further division, land plants are classified into two major groups according to the absence or presence of vascular tissue, as detailed in Figure 25.6. Plants that lack vascular tissue, which is formed of specialized cells for the transport of water and nutrients, are referred to as non-vascular plants. Liverworts, mosses, and hornworts are seedless, non-vascular plants that likely appeared early in land plant evolution. Vascular plants developed a network of cells that conduct water and solutes. The first vascular plants appeared in the late Ordovician and were probably similar to lycophytes, which include club mosses (not to be confused with the mosses) and the pterophytes (ferns, horsetails, and whisk ferns). Lycophytes and pterophytes are referred to as seedless vascular plants, because they do not produce seeds. The seed plants, or spermatophytes, form the largest group of all existing plants, and hence dominate the landscape. Seed plants include gymnosperms, most notably conifers (Gymnosperms), which produce \u201cnaked seeds,\u201d and the most successful of all plants, the flowering plants (Angiosperms). Angiosperms protect their seeds inside chambers at the center of a flower; the walls of the chamber later develop into a fruit.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The burning of fossil fuels has increased which effect?","choices":["natural gas effect","photosynthesis effect","ozone effect","greenhouse effect"],"answer":"D","rationale":"The burning of fossil fuels has increased the greenhouse effect and caused global climate change. Increasing temperatures are changing basic climate factors of habitats, and rising sea levels are covering them with water. These changes threaten many species.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call geographical areas that contain high numbers of endemic species?","choices":["warmspots","multispots","hotspots","endospots"],"answer":"C","rationale":"A simple measure of success in setting aside preserves for biodiversity protection is to set a target percentage of land or marine habitat to protect. However, a more detailed preserve design and choice of location is usually necessary because of the way protected lands are allocated and how biodiversity is distributed: protected lands tend to contain less economically valuable resources rather than being set aside specifically for the species or ecosystems at risk. In 2003, the IUCN World Parks Congress estimated that 11.5 percent of Earth\u2019s land surface was covered by preserves of various kinds. This area is greater than previous goals; however, it only represents 9 out of 14 recognized major biomes and research has shown that 12 percent of all species live outside preserves; these percentages are much higher when threatened species are considered and when only high quality preserves are considered. For example, high quality preserves include only about 50 percent of threatened amphibian species. The conclusion must be that either the percentage of area protected must be increased, the percentage of high quality preserves must be increased, or preserves must be targeted with greater attention to biodiversity protection. Researchers argue that more attention to the latter solution is required. A biodiversity hotspot is a conservation concept developed by Norman Myers in 1988. Hotspots are geographical areas that contain high numbers of endemic species. The purpose of the concept was to identify important locations on the planet.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of climate do most agaves grow in?","choices":["rainforest","tropical","arid","arctic"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die?","choices":["erythrocytes","sertoli cells","neurons","egg cells"],"answer":"B","rationale":"Sertoli Cells Surrounding all stages of the developing sperm cells are elongate, branching Sertoli cells. Sertoli cells are a type of supporting cell called a sustentacular cell, or sustenocyte, that are typically found in epithelial tissue. Sertoli cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die. They extend physically around the germ cells from the peripheral basement membrane of the seminiferous tubules to the lumen. Tight junctions between these sustentacular cells create the blood\u2013testis barrier, which keeps bloodborne substances from reaching the germ cells and, at the same time, keeps surface antigens on developing germ cells from escaping into the bloodstream and prompting an autoimmune response.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Invertebrate chordates use what to filter food out of water?","choices":["pores","tails","nose","gills"],"answer":"D","rationale":"Invertebrate chordates use their gills to filter food out of water, not to absorb oxygen. In the early evolution of fish, there was a switch to using gills to absorb oxygen instead of to filter food. Gills consist of many thin, folded tissues that provide a large surface area for oxygen uptake. With more oxygen absorbed by the gills, fish could become much larger and more active.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Because the current is alternating, the magnetic field of the iron core keeps doing what?","choices":["changing","decreasing","reversing","increasing"],"answer":"C","rationale":"The transformer in the diagram consists of two wire coils wrapped around an iron core. Each coil is part of a different circuit. When alternating current passes through coil P, it magnetizes the iron core. Because the current is alternating, the magnetic field of the iron core keeps reversing. This is where electromagnetic induction comes in. The changing magnetic field induces alternating current in coil S of the other circuit.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When heat moves out of a system, what is the sign of the enthalpy?","choices":["positive","N\/A (zero)","negative","it depends"],"answer":"C","rationale":"where H is the enthalpy of the system, E is the internal energy, P is the pressure, and V is the volume. It can be difficult to distinguish \"heat\" and \"enthalpy. \" Heat measures the transfer of thermal energy between two objects, and enthalpy measures the flow of heat. When heat flows out of a system, the change in enthalpy is negative; when heat flows into a system, the change in enthalpy is positive. Enthalpy is a useful tool for characterizing chemical reactions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when light bumps into tiny particles of matter and spreads out in all directions?","choices":["darkness","scattering","rainbow effect","kaleidoscope"],"answer":"B","rationale":"Scattering occurs when light bumps into tiny particles of matter and spreads out in all directions. In the Figure below , beams of light from car headlights are shining through fog. The light is scattered by water droplets in the air, giving the headlights a \u201chalo\u201d appearance.","split":"validation","source_dataset":"sciq","subject":null},{"question":"During unfavorable conditions, mature seeds may enter a period of inactivity or extremely low metabolic activity called what?","choices":["hibernation","malignancy","dormancy","germination"],"answer":"C","rationale":"Seed Germination Many mature seeds enter a period of inactivity, or extremely low metabolic activity: a process known as dormancy, which may last for months, years or even centuries. Dormancy helps keep seeds viable during unfavorable conditions. Upon a return to favorable conditions, seed germination takes place. Favorable conditions could be as diverse as moisture, light, cold, fire, or chemical treatments. After heavy rains, many new seedlings emerge. Forest fires also lead to the emergence of new seedlings. Some seeds require vernalization (cold treatment) before they can germinate. This guarantees that seeds produced by plants in temperate climates will not germinate until the spring. Plants growing in hot climates may have seeds that need a heat treatment in order to germinate, to avoid germination in the hot, dry summers. In many seeds, the presence of a thick seed coat retards the ability to germinate. Scarification, which includes mechanical or chemical processes to soften the seed coat, is often employed before germination. Presoaking in hot water, or passing through an acid environment, such as an animal\u2019s digestive tract, may also be employed. Depending on seed size, the time taken for a seedling to emerge may vary. Species with large seeds have enough food reserves to germinate deep below ground, and still extend their epicotyl all the way to the soil surface. Seeds of smallseeded species usually require light as a germination cue. This ensures the seeds only germinate at or near the soil surface (where the light is greatest). If they were to germinate too far underneath the surface, the developing seedling would not have enough food reserves to reach the sunlight.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Solid coal, liquid petroleum, and liquid natural gas are all types of what?","choices":["fossil fuels","hydroelectric","solar electric","nuclear fusion"],"answer":"A","rationale":"Fossil fuels include solid coal, liquid petroleum, and liquid natural gas.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What everyday beverage commodity is second only to oil in worldwide trade?","choices":["coffee","water","soda","beer"],"answer":"A","rationale":"Chemistry in Everyday Life Decaffeinating Coffee Using Supercritical CO2 Coffee is the world\u2019s second most widely traded commodity, following only petroleum. Across the globe, people love coffee\u2019s aroma and taste. Many of us also depend on one component of coffee\u2014caffeine\u2014to help us get going in the morning or stay alert in the afternoon. But late in the day, coffee\u2019s stimulant effect can keep you from sleeping, so you may choose to drink decaffeinated coffee in the evening. Since the early 1900s, many methods have been used to decaffeinate coffee. All have advantages and disadvantages, and all depend on the physical and chemical properties of caffeine. Because caffeine is.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where are ribosomes made?","choices":["mitochondria","the nucleolus","cell membrane","protoplasm"],"answer":"B","rationale":"The nucleolus is inside the nucleus, and is where ribosomes are made.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What prevents loss of water from the body and keeps out microorganisms?","choices":["sweat","the skin'","hydration","muscles"],"answer":"B","rationale":"The skin prevents loss of water from the body and keeps out microorganisms. Melanin in the epidermis protects the dermis from damaging ultraviolet light. By dilating or contracting its blood vessels and releasing sweat, skin helps maintain a constant body temperature.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Batteries containing a liquid electrolyte, like those in cars, are referred to as what kind of battery?","choices":["time cell","lithium cell","sand cell","wet cell"],"answer":"D","rationale":"The car battery is an example of a \u201cwet cell\u201d battery, because there is a liquid electrolyte (sulfuric acid) present in the system. These batteries must operate in an upright position so the liquid material does not spill out. In contrast, dry cell batteries contain a paste that serves as the positive electrode. The composition and voltage depends on the specific battery, but typical voltage outputs are in the 1.0-1.5 volt range.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Stp, which is important in determining information about gas behavior and properties, stands for standard temperature and what?","choices":["pressure","power","pull","push"],"answer":"A","rationale":"It should be obvious by now that some physical properties of gases depend strongly on the conditions. What we need is a set of standard conditions so that properties of gases can be properly compared to each other. Standard temperature and pressure (STP) is defined as exactly 100 kPa of pressure (0.986 atm) and 273 K (0\u00b0C). For simplicity, we will use 1 atm as standard pressure. Defining STP allows us to compare more directly the properties of gases that differ from each other. One property shared among gases is a molar volume. The molar volume is the volume of 1 mol of a gas. At STP, the molar volume of a gas can be easily determined by using the ideal gas law:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Within a particular habitat, what can be characterized by its size or density?","choices":["percent","population","group","total"],"answer":"B","rationale":"Population Size and Density The study of any population usually begins by determining how many individuals of a particular species exist, and how closely associated they are with each other. Within a particular habitat, a population can be characterized by its population size (N), the total number of individuals, and its population density, the number of individuals within a specific area or volume. Population size and density are the two main characteristics used to describe and understand populations. For example, populations with more individuals may be more stable than smaller populations based on their genetic variability, and thus their potential to adapt to the environment. Alternatively, a member of a population with low population density (more spread out in the habitat), might have more difficulty finding a mate to reproduce compared to a population of higher density. As is shown in Figure 45.2, smaller organisms tend to be more densely distributed than larger organisms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Animals that eat decomposing organic material, such as dung beetles, make the material available to what organisms that break it down further?","choices":["bacteria","pathogens","consumers","protozoa"],"answer":"A","rationale":"Animals that eat decomposing organic material also have an important interaction with the environment. They help to decompose dead matter and assist with the recycling of nutrients. By burying and eating dung, dung beetles, such as the one shown in Figure below , improve nutrient cycling and soil structure. They make the dead organic matter available to bacteria that break it down even further.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Skin that acts as camouflage or secretes chemicals poisonous to predators are successful modification in frogs and salamanders, classed as what in the order anura?","choices":["fungi","amphibians","reptiles","parasites"],"answer":"B","rationale":"View River Monsters: Fish With Arms and Hands? (http:\/\/openstaxcollege. org\/l\/river_monster) to see a video about an unusually large salamander species. Anura: Frogs Frogs are amphibians that belong to the order Anura (Figure 29.17). Anurans are among the most diverse groups of vertebrates, with approximately 5,965 species that occur on all of the continents except Antarctica. Anurans have a body plan that is more specialized for movement. Adult frogs use their hind limbs to jump on land. Frogs have a number of modifications that allow them to avoid predators, including skin that acts as camouflage. Many species of frogs and salamanders also release defensive chemicals from glands in the skin that are poisonous to predators.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call people who study science and are experts in one or more fields of science?","choices":["chemists","scientists","animals","doctors"],"answer":"B","rationale":"Scientists are regular people who chose to study science. They are experts in done or more fields of science.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In budding , organisms reproduce by having new individuals split off from what?","choices":["nuclei","ova","a sister chromatid","existing ones"],"answer":"D","rationale":"In budding , organisms reproduce by having new individuals split off from existing ones, which results in genetically identical parent and daughter organisms. The bud may stay attached or break free from the parent. Eukaryotic organisms, such as the single cell yeast and multicellular hydra, undergo budding ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What planet, covered by a thick layer of clouds, looks smooth and featureless through a telescope?","choices":["uranus","mars","Earth","venus"],"answer":"D","rationale":"Viewed through a telescope, Venus looks smooth and featureless. The planet is covered by a thick layer of clouds. You can see the clouds in pictures of Venus, such as Figure below . We make maps of the surface using radar, because the thick clouds won\u2019t allow us to take photographs of the surface of Venus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of power is generated via underground sources of heat?","choices":["solar","hydrothermal","volcanic","geothermal"],"answer":"D","rationale":"Geothermal energy is an excellent resource in some parts of the world. Iceland is gets about one fourth of its electricity from geothermal sources. In the United States, California leads all states in producing geothermal energy. Geothermal energy in California is concentrated in the northern part of the state. The largest plant is in the Geysers Geothermal Resource Area. Geothermal energy is not economical everywhere. Many parts of the world do not have underground sources of heat that are close enough to the surface for building geothermal power plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Saturn is made mostly of what two elements?","choices":["nitrogen and boron","carbon and oxygen","helium and lithium","hydrogen and helium"],"answer":"D","rationale":"Saturn\u2019s composition is similar to Jupiter's. The planet is made mostly of hydrogen and helium. These elements are gases in the outer layers and liquids in the deeper layers. Saturn may also have a small solid core. Saturn's upper atmosphere has clouds in bands of different colors. These clouds rotate rapidly around the planet. But Saturn has fewer storms than Jupiter. Thunder and lightning have been seen in the storms on Saturn.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A homogeneous mixture composed of two or more substances is called a what?","choices":["element","solution","mixture","structure"],"answer":"B","rationale":"Water is one of the most common ingredients in solutions. A solution is a homogeneous mixture composed of two or more substances. In a solution, one substance is dissolved in another substance, forming a mixture that has the same proportion of substances throughout. The dissolved substance in a solution is called the solute . The substance in which it is dissolved is called the solvent . An example of a solution in which water is the solvent is salt water. In this solution, a solid\u2014sodium chloride\u2014is the solute. In addition to a solid dissolved in a liquid, solutions can also form with solutes and solvents in other states of matter. Examples are given in the Table below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for particles composed of three quarks?","choices":["tachyons","nucleons","mesons","baryons"],"answer":"D","rationale":"Particles that are composed of three quarks are called baryons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in metabolism of what?","choices":["proteins","lipids","sugar","fats"],"answer":"C","rationale":"Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in sugar metabolism. Is the conversion of glycerol to glyceric acid an oxidative process or a reductive process? b. How many of these compounds are chiral? Indicate any chiral centers with an asterisk.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Instead of insects, crustaceans are the dominant arthropods in what environment?","choices":["marine habitat","tundra habitat","desert habitat","arid habitat"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and what two categories of reasoning?","choices":["existence and deduction","induction and deduction","reduction and deduction","method and deduction"],"answer":"B","rationale":"2.2 Nature of science Science is a methodology for learning about the world. It involves the application of knowledge. The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and reasoning. Reasoning can be broken down into two categories, induction (specific data is used to develop a generalized observation or conclusion) and deduction (general information leads to specific conclusion). Most reasoning in science is done through induction. Science as we now know it arose as a discipline in the 17th century.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is an example of a predator-prey relationship that helps maintain the balance of organisms in ecosystems?","choices":["lion and zebra","zebra and air","lion and grass","zebra and elephant"],"answer":"A","rationale":"Predation is another mechanism in which species interact with each other. Predation is when a predator organism feeds on another living organism or organisms, known as prey . The predator always lowers the prey\u2019s fitness . It does this by keeping the prey from surviving, reproducing, or both. Predator-prey relationships are essential to maintaining the balance of organisms in an ecosystem. Examples of predator-prey relationships include the lion and zebra, the bear and fish, and the fox and rabbit.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The 'boy in the bubble' is a classic example of someone suffering what type of disease that can cause opportunistic infections?","choices":["inherited immunodeficiency","muscular dystrophy","hydroencephaly","retardation"],"answer":"A","rationale":"Inherited Immunodeficiencies A list of all inherited immunodeficiencies is well beyond the scope of this book. The list is almost as long as the list of cells, proteins, and signaling molecules of the immune system itself. Some deficiencies, such as those for complement, cause only a higher susceptibility to some Gram-negative bacteria. Others are more severe in their consequences. Certainly, the most serious of the inherited immunodeficiencies is severe combined immunodeficiency disease (SCID). This disease is complex because it is caused by many different genetic defects. What groups them together is the fact that both the B cell and T cell arms of the adaptive immune response are affected. Children with this disease usually die of opportunistic infections within their first year of life unless they receive a bone marrow transplant. Such a procedure had not yet been perfected for David Vetter, the \u201cboy in the bubble,\u201d who was treated for SCID by having to live almost his entire life in a sterile plastic cocoon for the 12 years before his death from infection in 1984. One of the features that make bone marrow transplants work as well as they do is the proliferative capability of hematopoietic stem cells of the bone marrow. Only a small amount of bone marrow from a healthy donor is given intravenously to the recipient. It finds its own way to the bone where it populates it, eventually reconstituting the patient\u2019s immune system, which is usually destroyed beforehand by treatment with radiation or chemotherapeutic drugs. New treatments for SCID using gene therapy, inserting nondefective genes into cells taken from the patient and giving them back, have the advantage of not needing the tissue match required for standard transplants. Although not a standard treatment, this approach holds promise, especially for those in whom standard bone marrow transplantation has failed.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What phase does dna replication occur in the cell cycle?","choices":["Gap 0","apoptosis","synthesis","Mitosis"],"answer":"C","rationale":"DNA replication occurs during the S phase (the Synthesis phase) of the cell cycle, before mitosis and cell division. The base pairing rules are crucial for the process of replication. DNA replication occurs when DNA is copied to form an identical molecule of DNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of rocks form when magma cools and forms crystals?","choices":["metarmorphic","sedimentary","seismic","igneous"],"answer":"D","rationale":"Igneous rocks form when magma cools and forms crystals. These rocks can form at Earth\u2019s surface or deep underground. Figure below shows a landscape in California\u2019s Sierra Nevada that consists entirely of granite.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What determines the color of a star?","choices":["size of the star","age of the star","core temperature","surface temperature"],"answer":"D","rationale":"The color of a star is determined by its surface temperature.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Why do birds build nests?","choices":["raise birds","get off ground","safe place","hatch eggs"],"answer":"C","rationale":"Birds and wasps build nests to have a safe place to store their eggs and raise their young. Many other animals build nests for the same reason. Animals protect their young in other ways, as well. For example, a mother dog not only nurses her puppies. She also washes them with her tongue and protects them from strange people or other animals. All of these behaviors help the young survive and grow up to be adults.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Flagella, cilia and pseudopods are appendages that protists use for what purpose?","choices":["pressure","gravity","momentum","movement"],"answer":"D","rationale":"Most protists have motility . This is the ability to move. Protists have three types of appendages for movement. As shown in Figure below , they may have flagella, cilia , or pseudopods (\u201cfalse feet\u201d). There may be one or more whip-like flagella. Cilia are similar to flagella, except they are shorter and there are more of them. They may completely cover the surface of the protist cell. Pseudopods are temporary, foot-like extensions of the cytoplasm.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. such crystals are said to be this?","choices":["opaque matter","birefringent","reflective","phosphorescent"],"answer":"B","rationale":"Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. Such crystals are said to be birefringent (see Figure 27.50). Each of the separated rays has a specific polarization. One behaves normally and is called the ordinary ray, whereas the other does not obey Snell\u2019s law and is called the extraordinary ray. Birefringent crystals can be used to produce polarized beams from unpolarized light. Some birefringent materials preferentially absorb one of the polarizations. These materials are called dichroic and can produce polarization by this preferential absorption. This is fundamentally how polarizing filters and other polarizers work. The interested reader is invited to further pursue the numerous properties of materials related to polarization.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A mitotic spindle forms from the what?","choices":["ribosomes","centrosomes","sister chromatids","centrioles"],"answer":"B","rationale":"A mitotic spindle forms from the centrosomes. The nuclear envelope dissolves. Chromosomes attach to the mitotic spindle, which separates the chromosomes and elongates the cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the transfer of thermal energy between objects that have different temperatures?","choices":["warm","heat","humidity","sweat"],"answer":"B","rationale":"Heat is the transfer of thermal energy between objects that have different temperatures. Thermal energy always moves from an object with a higher temperature to an object with a lower temperature. Specific heat is the amount of energy (in joules) needed to raise the temperature of 1 gram of a substance by 1\u00b0C. Substances differ in their specific heat.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process in which cells make proteins called?","choices":["catalysis","synthesis","apoptosis","respiration"],"answer":"B","rationale":"The process in which cells make proteins is called protein synthesis . It actually consists of two processes: transcription and translation. Transcription takes place in the nucleus. It uses DNA as a template to make an RNA molecule. RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Living things on the ocean floor are known as?","choices":["newts","benthos","protozoa","decomposers"],"answer":"B","rationale":"Benthos are living things on the ocean floor. Many benthic organisms attach themselves to rocks and stay in one place. This protects them from crashing waves and other water movements. Some benthic organisms burrow into sediments for food or protection. Benthic animals may crawl over the ocean floor. Examples of benthos include clams and worms. Figure below shows two other examples.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A double form of what reproductive process is unique to angiosperms?","choices":["stimulation","fertilization","infection","destruction"],"answer":"B","rationale":"Figure 14.26 This diagram shows the lifecycle of an angiosperm. Anthers and ovaries are structures that shelter the actual gametophytes: the pollen grain and embryo sac. Double fertilization is a process unique to angiosperms. (credit: modification of work by Mariana Ruiz Villareal).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the conversion of a liquid to its vapor below the boiling temperature of the liquid?","choices":["evaporation","absorption","vaporization","oxidation"],"answer":"A","rationale":"Evaporation is the conversion of a liquid to its vapor below the boiling temperature of the liquid.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of energy conversion is done by a fuel cell?","choices":["chemical into electrical","solar into chemical","electrical into nuclear","wind into nuclear"],"answer":"A","rationale":"Fuel Cells A fuel cell is a device that converts chemical energy into electrical energy. Fuel cells are similar to batteries but require a continuous source of fuel, often hydrogen. They will continue to produce electricity as long as fuel is available. Hydrogen fuel cells have been used to supply power for satellites, space capsules, automobiles, boats, and submarines (Figure 17.15).","split":"validation","source_dataset":"sciq","subject":null},{"question":"In which aspect does molality differ from molarity?","choices":["complexity","accuracy","denominator","numerator"],"answer":"C","rationale":"Molality differs from molarity only in the denominator. While molarity is based on the liters of solution, molality is based on the kilograms of solvent. Concentrations expressed in molality are used when studying properties of solutions related to vapor pressure and temperature changes. Molality is used because its value does not change with changes in temperature. The volume of a solution, on the other hand, is slightly dependent upon temperature.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the mass that is \"lost\" in fission or fusion actually converted to?","choices":["pressure","momentum","hydrogen","energy"],"answer":"D","rationale":"When the nucleus of a radioisotope undergoes fission or fusion, it loses a tiny amount of mass. What happens to the lost mass? It isn\u2019t really lost at all. It is converted to energy. How much energy? . The change in mass is tiny, but it results in a great deal of energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What does a glacier leave behind when it retreats?","choices":["Dirt","sediment","bare rock","Lakes"],"answer":"C","rationale":"a glacier retreats and leaves behind bare rock.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What law states that matter cannot be created or destroyed even when it changes?","choices":["modification of mass","Action of mass","Transfer of mass","conservation of mass"],"answer":"D","rationale":"Matter cannot be created or destroyed even when it changes. This is the law of conservation of mass.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are natural sponges made of?","choices":["sea shells","sand","sea animals","sea plants"],"answer":"C","rationale":"Natural sponges, like the one in the picture above, are actually animals taken from the sea! The sponges in your home, however, were most likely never living things. Most sponges used in kitchens today are made from unnatural materials.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The process in which certain bacteria change nitrogen gas to a form that plants can absorb through their roots is known as what?","choices":["pollen fixation","dioxide fixation","nitrogen fixation","oxygen fixation"],"answer":"C","rationale":"Even though nitrogen gas makes up most of Earth's atmosphere, plants cannot use this nitrogen gas to make organic compounds for themselves and other organisms. The two nitrogen atoms in a molecule of nitrogen gas are held together by a very stable triple bond. This bond must be broken for the nitrogen to be used. The nitrogen gas must be changed to a form called nitrates, which plants can absorb through their roots. The process of changing nitrogen gas to nitrates is called nitrogen fixation . It is carried out by nitrogen-fixing bacteria. The bacteria live in soil and roots of legumes, such as peas.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What gas is actually a waste product of photosynthesis?","choices":["hydrogen","carbon dioxide","nitrogen","oxygen"],"answer":"D","rationale":"Around 3 billion years ago, photosynthesis began. Organisms could make their own food from sunlight and inorganic molecules. From these ingredients they made chemical energy that they used. Oxygen is a waste product of photosynthesis. That first oxygen combined with iron to create iron oxide. Later on, the oxygen entered the atmosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Distinguished by the great red spot, what planet has an upper atmosphere containing ammonia clouds?","choices":["mars","saturn","jupiter","uranus"],"answer":"C","rationale":"Jupiter's atmosphere is unlike any other in the solar system! The upper layer contains clouds of ammonia. The ammonia is different colored bands. These bands rotate around the planet. The ammonia also swirls around in tremendous storms. The Great Red Spot ( Figure below ) is Jupiter's most noticeable feature. The spot is an enormous, oval-shaped storm. It is more than three times as wide as Earth! Clouds in the storm rotate counterclockwise. They make one complete turn every six days or so. The Great Red Spot has been on Jupiter for at least 300 years. It may have been observed as early as 1664. It is possible that this storm is a permanent feature on Jupiter. No one knows for sure.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What controls what goes in and out of a cell?","choices":["the cilia","the nucleus","the mitochondria","the plasma membrane"],"answer":"D","rationale":"The function of the plasma membrane is to control what goes in and out of the cell. Some molecules can go through the cell membrane to enter and leave the cell, but some cannot. The cell is therefore not completely permeable. \"Permeable\" means that anything can cross a barrier. An open door is completely permeable to anything that wants to enter or exit through the door. The plasma membrane is semipermeable , meaning that some things can enter the cell, and some things cannot.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as what?","choices":["solid","stable","even","closed"],"answer":"B","rationale":"Each nucleus, therefore, has competing forces. The repulsive force between the protons tends to blow the nucleus apart and the binding energy tends to hold the nucleus together. If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as stable. If the repulsion overcomes the average binding energy per nucleon, the nucleus may blow apart or undergo nuclear disintegration . When a nucleus disintegrates, it throws off pieces of itself and energy in the form of gamma rays . This disintegration process came to be called radioactivity .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is mollusks complete digestive system called?","choices":["choroid","vesicle","thallus","coelom"],"answer":"D","rationale":"Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Kinetic energy is the energy of what?","choices":["wind","heat","light","motion"],"answer":"D","rationale":"Kinetic energy is the energy of motion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which area in a lake is likely to have more nutrients?","choices":["bottom","surface","crust","reef"],"answer":"A","rationale":"Water near the bottom of lakes and the ocean may contain more nutrients than water closer to the surface. When aquatic organisms die, they sink to the bottom. Decomposers near the bottom of the water break down the dead organisms and release their nutrients back into the water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Temperature is a measure of how hot or cold an object is relative to another object, whereas heat is the flow of what energy between objects with different temperatures?","choices":["potential energy","thermal energy","nuclear energy","gravitational energy"],"answer":"B","rationale":"Temperature The concept of temperature may seem familiar to you, but many people confuse temperature with heat. Temperature is a measure of how hot or cold an object is relative to another object (its thermal energy content), whereas heat is the flow of thermal energy between objects with different temperatures. Three different scales are commonly used to measure temperature: Fahrenheit (expressed as \u00b0F), Celsius (\u00b0C), and Kelvin (K). Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Scientists use seismographs and intersecting circles to determine the location of what?","choices":["tsunami","earthquake epicenter","volcano","hurricane"],"answer":"B","rationale":"Next, the seismologists try to determine the location of the earthquake epicenter. To do this they need the distances to the epicenter from at least three seismographs. Let\u2019s say that they know that an earthquake\u2019s epicenter is 50 kilometers from Kansas City. They draw a circle with a 50 km radius around that seismic station. They do this twice more around two different seismic stations. The three circles intersect at a single point. This is the earthquake\u2019s epicenter ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What happens when iron is exposed to water and oxygen?","choices":["smoking","rusting","combustion","shrinking"],"answer":"B","rationale":"Corrosion involves the formation of an oxidized form of a metal by an electrochemical process. A common example is the rusting of iron when exposed to water and oxygen. The tarnishing of silver and the red or green deposits formed on copper are other examples. Corrosion in all its forms costs the U. S. millions of dollars each year in expenses for metal replacement.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What disease is generally caused by mutations in genes that regulate the cell cycle?","choices":["arthritis","heart disease","cancer","pneumonia"],"answer":"C","rationale":"Cancer is a disease in which cells grow out of control and form abnormal masses of cells. It is generally caused by mutations in genes that regulate the cell cycle. Because of the mutations, cells with damaged DNA are allowed to divide without limits. Cancer causing genes can be inherited. You can learn more about hereditary cancer by watching the video at the following link: http:\/\/www. youtube. com\/watch?v=LWk5FplsKwM (4:29).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Proteins are organic compounds made up of what type of acids?","choices":["amino","lactic","nucleic","enzyme"],"answer":"A","rationale":"Proteins are organic compounds made up of amino acids. They form muscles, speed up chemical reactions, and perform many other cellular functions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Speciation is usually due to a single instance of what?","choices":["division","accumulation","radiation","mutation"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the extra layer that prokaryotes have outside the cell wall?","choices":["a shape","a bone","a shell","a capsule"],"answer":"D","rationale":"Many prokaryotes have an extra layer, called a capsule, outside the cell wall. The capsule protects the cell from chemicals and from drying out. It also allows the cell to stick to surfaces and to other cells. Because of this, many prokaryotes can form biofilms, like the one shown in Figure below . A biofilm is a colony of prokaryotes that is stuck to a surface such as a rock or a host\u2019s tissues. The sticky plaque that collects on your teeth between brushings is a biofilm. It consists of millions of bacteria.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The binary halides are an important subclass of what?","choices":["minerals","gases","acids","salts"],"answer":"D","rationale":"Halides of the Representative Metals Thousands of salts of the representative metals have been prepared. The binary halides are an important subclass of salts. A salt is an ionic compound composed of cations and anions, other than hydroxide or oxide ions. In general, it is possible to prepare these salts from the metals or from oxides, hydroxides, or carbonates. We will illustrate the general types of reactions for preparing salts through reactions used to prepare binary halides. The binary compounds of a metal with the halogens are the halides. Most binary halides are ionic. However, mercury, the elements of group 13 with oxidation states of 3+, tin(IV), and lead(IV) form covalent binary halides. The direct reaction of a metal and a halogen produce the halide of the metal. Examples of these oxidation-reduction reactions include: Cd(s) + Cl 2(g) \u27f6 CdCl 2(s) 2Ga(l) + 3Br 2(l) \u27f6 2GaBr 3(s).","split":"validation","source_dataset":"sciq","subject":null},{"question":"When was construction of the hoover dam completed?","choices":["1935","1959","1905","1969"],"answer":"A","rationale":"If you take a trip out of Las Vegas toward Phoenix you can visit the Hoover Dam. Completed in 1935, the dam provides power to over a million homes. It also stores water for use by the residents of the desert southwest. Hoover Dam is one of the engineering marvels of the 20th century.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some plants can produce seeds without fertilization and this method of reproduction is known as what?","choices":["gametes","amoebas","Density","apomixis"],"answer":"D","rationale":"Some plants can produce seeds without fertilization. Either the ovule or part of the ovary, which is diploid in nature, gives rise to a new seed. This method of reproduction is known as apomixis. An advantage of asexual reproduction is that the resulting plant will reach maturity faster. Since the new plant is arising from an adult plant or plant parts, it will also be sturdier than a seedling. Asexual reproduction can take place by natural or artificial (assisted by humans) means.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of chains do unsaturated fatty acids have?","choices":["Broken Chains","Spiral Chains","Stait Chains","bent chains"],"answer":"D","rationale":"Fatty Acids. Saturated fatty acids have straight chains, like the three fatty acids shown in the upper left. Unsaturated fatty acids have bent chains, like all the other fatty acids in the figure.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ribosomes are the site of what process?","choices":["protein synthesis","consume synthesis","Measure Synthesis","organism synthesis"],"answer":"A","rationale":"8.5 Ribosomes Ribosomes are the site of protein synthesis. Ribosomes themselves are synthesized in the cell nucleoli28 and are structured as two subunits, the large and the small. These parts are composed of RNA and protein. Prokaryotic and eukaryotic ribosomes are different, the eukaryotic ones being larger and more complicated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Bacteria and archaea that survive under extreme conditions are called?","choices":["extremophiles","rotifers","audiophiles","carotenoids"],"answer":"A","rationale":"phototrophs and began the oxygenation of the atmosphere. The increase in oxygen concentration allowed the evolution of other life forms. Fossilized microbial mats are called stromatolites and consist of laminated organo-sedimentary structures formed by precipitation of minerals by prokaryotes. They represent the earliest fossil record of life on Earth. Bacteria and archaea grow in virtually every environment. Those that survive under extreme conditions are called extremophiles (extreme lovers). Some prokaryotes cannot grow in a laboratory setting, but they are not dead. They are in the viable-but-non-culturable (VBNC) state. The VBNC state occurs when prokaryotes enter a dormant state in response to environmental stressors. Most prokaryotes are social and prefer to live in communities where interactions take place. A biofilm is a microbial community held together in a gummy-textured matrix.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The production and transport of gametes is performed by what type of organs?","choices":["reproductive","skin","digestion","degradation"],"answer":"A","rationale":"46.3 Reproductive organs produce and transport gametes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are atoms of the same element but with different numbers of neutrons called?","choices":["variations","electrons","masses","isotopes"],"answer":"D","rationale":"Isotopes are atoms of the same element but with different numbers of neutrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Active transport mechanisms require the use of the cell\u2019s energy, usually in the form of what?","choices":["adenosine triphosphate (atp","deoxyribonucleic acid (DNA)","protein","ribonucleic acid (RNA)"],"answer":"A","rationale":"3.6 | Active Transport By the end of this section, you will be able to: \u2022 Understand how electrochemical gradients affect ions \u2022 Describe endocytosis, including phagocytosis, pinocytosis, and receptor-mediated endocytosis \u2022 Understand the process of exocytosis Active transport mechanisms require the use of the cell\u2019s energy, usually in the form of adenosine triphosphate (ATP). If a substance must move into the cell against its concentration gradient, that is, if the concentration of the substance inside the cell must be greater than its concentration in the extracellular fluid, the cell must use energy to move the substance. Some active transport mechanisms move small-molecular weight material, such as ions, through the membrane. In addition to moving small ions and molecules through the membrane, cells also need to remove and take in larger molecules and particles. Some cells are even capable of engulfing entire unicellular microorganisms. You might have correctly hypothesized that the uptake and release of large particles by the cell requires energy. A large particle, however, cannot pass through the membrane, even with energy supplied by the cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of energy can move through glass much better than through paper?","choices":["sound","light","heat","vibrational"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What forms when one substance dissolves into another?","choices":["compound","solvent","solution","mixture"],"answer":"C","rationale":"When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What transition occurs as heat is added or removed from a substance?","choices":["phase transition","thermal reaction","heat wave","diffusion transition"],"answer":"A","rationale":"Phase transitions occur as heat is added or removed from a substance.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the predicted year that as many as half of all remaining species could go extinct?","choices":["2040","2050","2020","3000"],"answer":"B","rationale":"Evidence shows that a sixth mass extinction is happening right now. Species are currently going extinct at the fastest rate since the dinosaurs died out. Dozens of species are going extinct every day. If this rate continues, as many as half of all remaining species could go extinct by 2050.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which scientist developed the theory of evolution and detailed it in the book origin of species?","choices":["Isaac Newton","charles darwin","Carl Sagan","Gregor Mendel"],"answer":"B","rationale":"In his book On the Origin of Species, Darwin included a lot of evidence to show that evolution had taken place. He also made logical arguments to support his theory that evolution occurs by natural selection. Since Darwin\u2019s time, much more evidence has been gathered. The evidence includes a huge number of fossils. It also includes more detailed knowledge of living things, right down to their DNA.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Insects are the only invertebrates that can do what?","choices":["shed","reproduce","vocalize","fly"],"answer":"D","rationale":"The main reason that insects have been so successful is their ability to fly. Insects are the only invertebrates that can fly. They were also the first animals to evolve flight. The ability to fly is highly adaptive. It\u2019s a guaranteed means of escape from nonflying predators. It\u2019s also useful for finding food and mates.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What basic structures, found in animals and plants, are organized into tissues, organs, and organ systems?","choices":["bones","seeds","proteins","cells"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we call the phase of nuclear division, in which one nucleus divides and becomes two nuclei?","choices":["prometaphase","cytokinesis","mitosis","metaphase"],"answer":"C","rationale":"Mitosis is the phase of nuclear division, in which one nucleus divides and becomes two nuclei. Mitosis itself is a multi-phase process and will be the focus of the Cell Cycle: Mitosis (Advanced) concept. Immediately following mitosis is cytokinesis, in which the cytoplasm divides in half, producing two daughter cells, each containing a complete set of genetic material.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In abalones and limpets, what is conical, but somewhat flattened?","choices":["the shell","the bone","the heart","the head"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the physical properties of water and carbon dioxide affected by?","choices":["weather","temperature","weight","their polarities"],"answer":"D","rationale":"The physical properties of water and carbon dioxide are affected by their polarities.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which one of newton's laws describes the direct relationship between force and acceleration?","choices":["second law","third law","fourth law","first law"],"answer":"A","rationale":"Newton\u2019s second law shows that there is a direct relationship between force and acceleration. The greater the force that is applied to an object of a given mass, the more the object will accelerate. For example, doubling the force on the object doubles its acceleration.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The process by which creatures regulate body temperature from the outside through behavioral changes is known as what?","choices":["ectothermy","misiothermy","endothermy","exterior induction"],"answer":"A","rationale":"Until mammals and birds evolved, all vertebrates were ectothermic. Ectothermy means regulating body temperature from the outside through behavioral changes. For example, an ectotherm might stay under a rock in the shade in order to keep cool on a hot, sunny day. Almost all living fish, amphibians, and reptiles are ectothermic. Their metabolic rate and level of activity depend mainly on the outside temperature. They can raise or lower their own temperature only slightly through behavior alone.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Because of moving charged particles in its outer core, earth is what?","choices":["magnet","transmitter","laser","antenna"],"answer":"A","rationale":"In this chapter, you learned that Earth is a magnet because of moving charged particles in its outer core. In the chapter \"Electricity,\" you learned that moving charged particles create electric current. The next chapter explains how electric current and magnetism are related.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Color, taste, and melting point are examples of what kind of properties?","choices":["intensive properties","experimental properties","sensory properties","extensive properties"],"answer":"A","rationale":"Intensive properties do not depend on the amount of the substance present. Some examples of intensive properties are color, taste, and melting point.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Amorphous selenium is a photosensitive what?","choices":["diffusion","electromagnet","insulator","semiconductor"],"answer":"D","rationale":"Because amorphous selenium is a photosensitive semiconductor, exposing an electrostatically charged Se film to light causes the positive charge on the film to be discharged in all areas that are white in the original. Dark areas in the original block the light and generate an invisible, positively charged image. To produce an image on paper, negatively charged toner particles are attracted to the positive image, transferred to a negatively charged sheet of blank paper, and fused with the paper at high temperature to give a permanent image. The heaviest chalcogen, polonium, was isolated after an extraordinary effort by Marie Curie. (For more information on radioactivity and polonium, see Chapter 1 \"Introduction to Chemistry\", Section 1.5 \"The Atom\". ) Although she was never able to obtain macroscopic quantities of the element, which she named for her native country of Poland, she demonstrated that its chemistry required it to be assigned to group 16. Marie Curie was awarded a second Nobel Prize in Chemistry in 1911 for the discovery of radium and polonium.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When the rate of condensation becomes equal to the rate of vaporization, the vapor in the container is then said to be in what with the liquid?","choices":["stability","synchronization","balance","equilibrium"],"answer":"D","rationale":"Vaporization and Condensation When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor in the container changes. The vapor in the container is then said to be in equilibrium with the liquid. Keep in mind that this is not a static situation, as molecules are continually exchanged between the condensed and gaseous phases. Such is an example of a dynamic equilibrium, the status of a system in.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the sources of sexual spores in a basidiocarp?","choices":["annulus","conidia","stamens","basidia"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Amylose and amylopectin are the two most common components of naturally occurring what?","choices":["carbon","starch","protein","chromosomes"],"answer":"B","rationale":"Amylose and amylopectin are the two most common components of naturally occurring starch. Both consist of many glucose monomers connected into a polymer. Starch serves as energy storage in plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Reactive, high polarized substances made of carbon bonded to one carbon atom and one hydrogen atom are known as what?","choices":["proteins","hydrocarbons","aldehydes","peptides"],"answer":"C","rationale":"Aldehydes are commonly composed of a carbon bonded to one carbon atom and one hydrogen atom. Aldehydes are particularly reactive due to their high polarity, and are commonly associated with strong smells and tastes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Relative humidity is related to the partial pressure of what in the air?","choices":["water vapor","gas vapor","solid vapor","air vapor"],"answer":"A","rationale":"Relative humidity is related to the partial pressure of water vapor in the air. At 100% humidity, the partial pressure is equal to the vapor pressure, and no more water can enter the vapor phase. If the partial pressure is less than the vapor pressure, then evaporation will take place, as humidity is less than 100%. If the partial pressure is greater than the vapor pressure, condensation takes place. In everyday language, people sometimes refer to the capacity of air to \u201chold\u201d water vapor, but this is not actually what happens. The water vapor is not held by the air. The amount of water in air is determined by the vapor pressure of water and has nothing to do with the properties of air.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the two stages in the life cycle of a jellyfish?","choices":["archangel and polyp","medusa and polyp","banshee and polyp","witch and polyp"],"answer":"B","rationale":"Figure 28.10 The lifecycle of a jellyfish includes two stages: the medusa stage and the polyp stage. The polyp reproduces asexually by budding, and the medusa reproduces sexually. (credit \"medusa\": modification of work by Francesco Crippa).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of the cell holds cell organelles in place within the cytoplasm?","choices":["cytoskeleton","nucleus","exoskeleton","call wall"],"answer":"A","rationale":"Crisscrossing the cytoplasm is a structure called the cytoskeleton . It consists of thread-like filaments and tubules. The cytoskeleton is like a cellular \u201cskeleton. \u201d It helps the cell keep its shape. It also holds cell organelles in place within the cytoplasm.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name for the process of insects transforming from a young insect to an adult?","choices":["metamorphosis","maturation","spontaneous mutation","parthenogenesis"],"answer":"A","rationale":"An insect can have one of three types of metamorphosis and life cycles ( Table below ). Metamorphosis describes how insects transform from an immature or young insect into an adult insect in at least two stages. Insects may undergo gradual metamorphosis (incomplete), where transformation is subtle, or complete metamorphosis, where each stage of the life cycle appears quite different from the others. In some insects, there may be no true metamorphosis at all.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Over time, heavy metals build up in the tissues of organisms by what process?","choices":["biosynthesis","solidification","oxygenation","bioaccumulation"],"answer":"D","rationale":"Heavy metals, such as mercury and lead, are toxic to living things. They can enter food chains from the atmosphere. The metals build up in the tissues of organisms by bioaccumulation . Bioaccumulation is illustrated in Figure below . As heavy metals are passed up a food chain they accumulate. Imagine a low-level consumer eating a producer. That consumer takes in all of the heavy metals from all of the producers that it eats. Then a higher-level consumer eats it and accumulates all the heavy metals from all of the lower-level consumers that it eats. In this way, heavy metals may accumulate. At high levels in the food chain, the heavy metals may be quite become quite concentrated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Changes to what that delete, disrupt, or rearrange many loci at once are usually harmful?","choices":["cells","ribosomes","chromosomes","neutrons"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The ability of a material to emit various wavelengths of light is similarly related to its?","choices":["molar mass","atomic energy levels","half-life","specific gravity"],"answer":"B","rationale":"Fluorescence and Phosphorescence The ability of a material to emit various wavelengths of light is similarly related to its atomic energy levels. Figure 30.31 shows a scorpion illuminated by a UV lamp, sometimes called a black light. Some rocks also glow in black light, the particular colors being a function of the rock\u2019s mineral composition. Black lights are also used to make certain posters glow.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Divergent plate boundaries rift what landforms apart, leading to the formation of a new ocean between them?","choices":["mountains","coasts","continents","islands"],"answer":"C","rationale":"Divergent plate boundaries rift a continent apart. Eventually a new ocean will form between the two continents.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What mineral is stored and is maintained at normal levels in blood by the skeletal system?","choices":["selenium","calcium","magnesium","potassium"],"answer":"B","rationale":"The skeletal system stores calcium and helps maintain normal levels of calcium in the blood. Bones take up and store calcium when blood levels of calcium are high. They release some of the stored calcium when blood levels of calcium are low.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of diseases are diseases that are caused by choices that people make in their daily lives?","choices":["benign diseases","lifestyle diseases","congenital diseases","contagious diseases"],"answer":"B","rationale":"We know that many respiratory illnesses are caused by bacteria or viruses. There are steps you can take to help the spread of these pathogens, and also to prevent you from catching one. Furthermore, many respiratory illnesses are caused by poor habits, such as smoking. Many of the diseases related to smoking are called lifestyle diseases . Lifestyle diseases are diseases that are caused by choices that people make in their daily lives. For example, the choice to smoke can lead to emphysema, cancer and heart disease in later life. But you can make healthy choices instead. There are many things you can do to keep yourself healthy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A barometer is a device that measures this?","choices":["humidity","water pressure","temperature","air pressure"],"answer":"D","rationale":"Weather instruments measure weather conditions. One of the most important conditions is air pressure, which is measured with a barometer . Figure below shows how a barometer works. There are also a number of other commonly used weather instruments (see Figure below ):.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for getting the same results when an experiment is repeated, which implies the results are valid?","choices":["extraction","evolution","verification","replication"],"answer":"D","rationale":"In its solid form, water is frequently referred to as ice. The terms snow, sleet, hail, or frost may also be used, depending on the conditions under which the water solidified. Ice can exist as an amorphous solid or as a crystalline solid.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Helices, spheres, and rods are examples of what distinguishing property of prokaryotic cells?","choices":["texture","size","shape","color"],"answer":"C","rationale":"Most prokaryotic cells are much smaller than eukaryotic cells. Although they are tiny, prokaryotic cells can be distinguished by their shapes. The most common shapes are helices, spheres, and rods (see Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the change in momentum vector?","choices":["impulse","gravity","variation","release"],"answer":"A","rationale":"Impulse is the change in momentum vector. Therefore the.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Larger molecules can have many, many of what that serve to keep the molecule together?","choices":["arms","connections","tubes","bonds"],"answer":"D","rationale":"Larger molecules can have many, many bonds that serve to keep the molecule together. In a large sample of a given molecular compound, all of the individual molecules are identical.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What makes nobel gases unreactive?","choices":["chemical reaction","its electon configuration","fusion","magnetism"],"answer":"B","rationale":"The noble gases are unreactive because of their electron configurations. American chemist Gilbert Lewis (1875-1946) used this observation to explain the types of ions and molecules that are formed by other elements. He called his explanation the octet rule. The octet rule states that elements tend to form compounds in ways that give each atom eight valence electrons. An exception to this rule is the elements in the first period, which are particularly stable when they have two valence electrons. A broader statement that encompasses both the octet rule and this exception is that atoms react in order to achieve the same valence electron configuration as that of the nearest noble gas. Most noble gases have eight valence electrons, but because the first principal energy level can hold a maximum of two electrons, the first noble gas (helium) needs only two valence electrons to fill its outermost energy level. As a result, the nearby elements hydrogen, lithium, and beryllium tend to form stable compounds by achieving a total of two valence electrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which joint allows humans to sit, stand, and pivot?","choices":["ankle","hip","femur","knee"],"answer":"D","rationale":"Figure 9.38 The knee joint works like a hinge to bend and straighten the lower leg. It permits a person to sit, stand, and pivot.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of power is generated by splitting uranium atoms?","choices":["wind power","solar power","nuclear power","fossil fuel power"],"answer":"C","rationale":"Nuclear power plants use uranium that has been concentrated in fuel rods ( Figure below ). The uranium atoms are split apart when they are hit by other extremely tiny particles. These particles must be controlled or they would cause a dangerous explosion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"At any given temperature, not all of the particles of a sample of matter have the same energy of what type?","choices":["magnetic","seismic","dark matter","kinetic"],"answer":"D","rationale":"At any given temperature, not all of the particles of a sample of matter have the same kinetic energy. Instead, the particles display a wide range of kinetic energies. Most of the particles have a kinetic energy near the middle of the range. However, a small number of particles have kinetic energies a great deal lower or a great deal higher than the average (see Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Individual particles of a substance in what state are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles?","choices":["solid","stable","undivided","structured"],"answer":"A","rationale":"Solids In the solid state, the individual particles of a substance are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles. As a result, solids have a definite shape and volume. Most solids are hard, but some (like waxes) are relatively soft. Many solids composed of ions can also be quite brittle. Solids usually have their constituent particles arranged in a regular, three-dimensional array of alternating positive and negative ions called a crystal. The effect of this regular arrangement of particles is sometimes visible macroscopically, as shown in Figure 8.7 \"Crystalline Arrangement\". Some solids, especially those composed of large molecules, cannot easily organize their particles in such regular crystals and exist as amorphous (literally, \u201cwithout form\u201d) solids. Glass is one example of an amorphous solid.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of feeders are sponges?","choices":["bottom feeders","surface feeders","filter feeders","primary feeders"],"answer":"C","rationale":"Sponges are filter feeders. They pump water into their body through their pores. The water flows through a large central cavity called the spongocoel (see Figure above ). As the water flows by, specialized collar cells (which are also known as choanocytes) filter out food particles such as bacteria. Collar cells have tiny hairs that trap the particles. They also have a flagellum that whips the water and keeps it moving. Once the food is trapped, the collar cells digest it (see Figure below ). Cells called amebocytes also help digest the food. They distribute the nutrients to the rest of the body as well. Finally, the water flows back out of the body through an opening called the osculum . As water flows through the sponge, oxygen diffuses from the water to the sponge\u2019s cells. The cells also expel wastes into the water for removal through the osculum.","split":"validation","source_dataset":"sciq","subject":null},{"question":"It is the variety of what that gives rise to the incredible variation of protein structure and function?","choices":["clump acid side chains","amino acid side chains","spastic acid side chains","organism acid side chains"],"answer":"B","rationale":"Figure 15.2 Structures of the 20 amino acids found in proteins are shown. Each amino acid is composed of an amino group ( NH+ 3 ), a carboxyl group (COO ), and a side chain (blue). The side chain may be nonpolar, polar, or charged, as well as large or small. It is the variety of amino acid side chains that gives rise to the incredible variation of protein structure and function.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do plant viruses have that protect their cells?","choices":["inner wall","proteins wall","nuclei wall","cell wall"],"answer":"D","rationale":"Plant Viruses Plant viruses, like other viruses, contain a core of either DNA or RNA. You have already learned about one of these, the tobacco mosaic virus. As plant viruses have a cell wall to protect their cells, these viruses do not use receptor-mediated endocytosis to enter host cells as is seen with animal viruses. For many plant viruses to be transferred from plant to plant, damage to some of the plants\u2019 cells must occur to allow the virus to enter a new host. This damage is often caused by weather, insects, animals, fire, or human activities like farming or landscaping. Additionally, plant offspring may inherit viral diseases from parent plants. Plant viruses can be transmitted by a variety of vectors, through contact with an infected plant\u2019s sap, by living organisms such as insects and nematodes, and through pollen. When plants viruses are transferred between different plants, this is known as horizontal transmission, and when they are inherited from a parent, this is called vertical transmission. Symptoms of viral diseases vary according to the virus and its host (Table 21.4). One common symptom is hyperplasia, the abnormal proliferation of cells that causes the appearance of plant tumors known as galls. Other viruses induce hypoplasia, or decreased cell growth, in the leaves of plants, causing thin, yellow areas to appear. Still other viruses affect the plant by directly killing plant cells, a process known as cell necrosis. Other symptoms of plant viruses include malformed leaves, black streaks on the stems of the plants, altered growth of stems, leaves, or fruits, and ring spots, which are circular or linear areas of discoloration found in a leaf.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of isotope can be used to treat diseases like cancer?","choices":["radiodecaying isotope","negative isotope","positive isotope","radioactive isotopes"],"answer":"D","rationale":"Radioactive isotopes are also used in the treatment of certain diseases, such as cancer. These isotopes are administered to only the diseased tissue, with the goal of destroying the unhealthy cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What helps by releasing chemicals that control other lymphocytes?","choices":["helper t cells","discharger t cells","interloper t cells","controller t cells"],"answer":"A","rationale":"Helper T cells do not destroy infected, damaged, or cancerous body cells. However, they are still needed for an immune response. They help by releasing chemicals that control other lymphocytes. The chemicals released by helper T cells \u201cswitch on\u201d B cells and killer T cells so they can recognize and fight specific pathogens.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the density needed to just halt universal expansion called?","choices":["instance density","stop density","critical density","allow density"],"answer":"C","rationale":"critical density, the density needed to just halt universal expansion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In a nuclear power plant, what typically spins in order to produce electricity?","choices":["turbine","grid","generator","pipe"],"answer":"A","rationale":"Nuclear power plants use the energy they produce to heat water. The water turns into steam, which causes a turbine to spin. This, in turn, produces electricity.","split":"validation","source_dataset":"sciq","subject":null},{"question":"How do roots and stems grow?","choices":["evenly","logically","indeterminately","orderly"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are organic molecules that consist of carbon, hydrogen, and oxygen called?","choices":["proteins","carbohydrates","amino acids","electrolytes"],"answer":"B","rationale":"Carbohydrates are organic molecules that consist of carbon, hydrogen, and oxygen. They are made up of repeating units called saccharides. They provide cells with energy, store energy, and form structural tissues.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The diploid sporophyte produces haploid spores by what process?","choices":["mitosis","binary fission","meiosis","electrolysis"],"answer":"C","rationale":"The diploid sporophyte produces haploid spores by meiosis.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms?","choices":["ionic","polar","acidic","nonpolar"],"answer":"D","rationale":"A bond in which the electronegativity difference is less than 1.7 is considered to be mostly covalent in character. However, at this point we need to distinguish between two general types of covalent bonds. A nonpolar covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms. In a nonpolar covalent bond, the distribution of electrical charge is balanced between the two atoms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What forms a barrier between the cytoplasm and the environment outside the cell?","choices":["the mitochondria membrane","the plasma membrane","the cellular membrane","the splatter membrane"],"answer":"B","rationale":"The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sponges are part of what phylum, which gets its name from the latin for \"having pores\"?","choices":["annelida","porifera","mammalia","chordata"],"answer":"B","rationale":"Sponges ( Figure below ) are classified in the phylum Porifera, from the Latin words meaning \"having pores. \" These pores allow the movement of water into the sponges\u2019 sac-like bodies. Sponges must pump water through their bodies in order to eat. Because sponges are sessile , meaning they cannot move, they filter water to obtain their food. They are, therefore, known as filter feeders. Filter feeders must filter the water to separate out the organisms and nutrients they want to eat from those they do not.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Comets that have periods of 200 years or less are knows as what-period comets?","choices":["old","long","short","fast"],"answer":"C","rationale":"Newly hatched loggerhead turtles start crossing the sand to the ocean.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The integumentary system helps regulate body temperature through its tight association with what system involved in our fight-or-flight responses?","choices":["endocrine system","autonomic nervous system","sympathetic nervous system","circulatory system"],"answer":"C","rationale":"Thermoregulation The integumentary system helps regulate body temperature through its tight association with the sympathetic nervous system, the division of the nervous system involved in our fight-or-flight responses. The sympathetic nervous system is continuously monitoring body temperature and initiating appropriate motor responses. Recall that sweat glands, accessory structures to the skin, secrete water, salt, and other substances to cool the body when it becomes warm. Even when the body does not appear to be noticeably sweating, approximately 500 mL of sweat (insensible perspiration) are secreted a day. If the body becomes excessively warm due to high temperatures, vigorous activity (Figure 5.16ac), or a combination of the two, sweat glands will be stimulated by the sympathetic nervous system to produce large amounts of sweat, as much as 0.7 to 1.5 L per hour for an active person. When the sweat evaporates from the skin surface, the body is cooled as body heat is dissipated. In addition to sweating, arterioles in the dermis dilate so that excess heat carried by the blood can dissipate through the skin and into the surrounding environment (Figure 5.16b). This accounts for the skin redness that many people experience when exercising.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What in the air allows us to hear sound?","choices":["wind","rain","water","gases"],"answer":"D","rationale":"Sound is a form of energy that travels in waves. Sound waves can\u2019t travel through empty space, but they can travel through gases. Gases in the air allow us to hear most of the sounds in our world. Because of air, you can hear birds singing, horns tooting, and friends laughing. Without the atmosphere, the world would be a silent, eerie place.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call the process in which a community changes through time?","choices":["ecological succession","natural selection","spontaneous mutation","continuous succession"],"answer":"A","rationale":"Ecological succession is the process in which a community changes through time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the maximum horizontal distance traveled by a projectile?","choices":["length","range","radius","span"],"answer":"B","rationale":"\u2022 The maximum horizontal distance traveled by a projectile is called the range. The range launched at an angle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The axon is a long extension of the cell body that transmits what to other cells?","choices":["synthesis impulses","calcium impulses","blood impulses","nerve impulses"],"answer":"D","rationale":"The axon is a long extension of the cell body that transmits nerve impulses to other cells. The axon branches at the end, forming axon terminals . These are the points where the neuron communicates with other cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Fungi are now classified as their own kingdom. what kingdom were they previously a part of?","choices":["arthropods","animals","protozoa","plants"],"answer":"D","rationale":"Today, fungi are no longer classified as plants. We now know that they have important traits that set them apart from plants. That\u2019s why they are placed in their own kingdom. How do fungi differ from plants?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for small streams?","choices":["tributaries","wetlands","rivers","canals"],"answer":"A","rationale":"Small streams often flow into bigger streams or rivers. The small streams are called tributaries . A river and all its tributaries make up a river system.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A comparison of the human arm with a bat's wing demonstrates what principle of biology?","choices":["size follows function","motion follows function","form follows function","attachment follows function"],"answer":"C","rationale":"dictates the form of that body part. As an example, compare your arm to a bat\u2019s wing. While the bones of the two correspond, the parts serve different functions in each organism and their forms have adapted to follow that function. 30 Centrioles and flagella are alike in that they are made up of microtubules. In centrioles, two rings of nine microtubule \u201ctriplets\u201d are arranged at right angles to one another. This arrangement does not occur in flagella. 32 They differ because plant cell walls are rigid. Plasmodesmata, which a plant cell needs for transportation and communication, are able to allow movement of really large molecules. Gap junctions are necessary in animal cells for transportation and communication.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What converters are used on motor vehicles to break down pollutants in exhaust to non-toxic compounds?","choices":["back converters","solvent converters","outer converters","catalytic converters"],"answer":"D","rationale":"Catalytic converters are used on motor vehicles. They break down pollutants in exhaust to non-toxic compounds. For example, they change nitrogen oxides to harmless nitrogen and oxygen gasses.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If a substance does not release molecules into the air from its surface, it will not have what?","choices":["taste","smell","temperature","color"],"answer":"B","rationale":"Tastes and Odors Both taste and odor stimuli are molecules taken in from the environment. The primary tastes detected by humans are sweet, sour, bitter, salty and umami. The first four tastes need little explanation. The identification of umami as a fundamental taste occurred fairly recently\u2014it was identified in 1908 by Japanese scientist Kikunae Ikeda while he worked with seaweed broth, but it was not widely accepted as a taste that could be physiologically distinguished until many years later. The taste of umami, also known as savoriness, is attributable to the taste of the amino acid L-glutamate. In fact, monosodium glutamate, or MSG, is often used in cooking to enhance the savory taste of certain foods. What is the adaptive value of being able to distinguish umami? Savory substances tend to be high in protein. All odors that we perceive are molecules in the air we breathe. If a substance does not release molecules into the air from its surface, it has no smell. And if a human or other animal does not have a receptor that recognizes a specific molecule, then that molecule has no smell. Humans have about 350 olfactory receptor subtypes that work in various combinations to allow us to sense about 10,000 different odors. Compare that to mice, for example, which have about 1,300 olfactory receptor types, and therefore probably sense more odors. Both odors and tastes involve molecules that stimulate specific chemoreceptors. Although humans commonly distinguish taste as one sense and smell as another, they work together to create the perception of flavor. A person\u2019s perception of flavor is reduced if he or she has congested nasal passages.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for when deep ocean water rises to the surface?","choices":["upwelling","tsunami","tidal waves","percolating"],"answer":"A","rationale":"Upwelling occurs when deep ocean water rises to the surface. The water brings nutrients with it. These nutrients support many organisms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are collisions between gas particles and container walls called?","choices":["kinetic theory","elastic collisions","tubes collisions","utilize collisions"],"answer":"B","rationale":"Collisions between gas particles and between particles and the container walls are elastic collisions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to \u221221 \u00b0c produces what?","choices":["nitrate trioxide","dinitrogen trioxide","carbon trioxide","chloride trioxide"],"answer":"B","rationale":"Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to \u221221 \u00b0C produces dinitrogen trioxide, a blue liquid consisting of N2O3 molecules (shown in Figure 18.35). Dinitrogen trioxide exists only in the liquid and solid states. When heated, it reverts to a mixture of NO and NO2.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most important element to life?","choices":["nitrogen","carbon","hydrogen","calcium"],"answer":"B","rationale":"Carbon is the most important element to life. Without this element, life as we know it would not exist. As you will see, carbon is the central element in compounds necessary for life.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each female of a particular species can produce millions of these per year?","choices":["sperms","seeds","eggs","fetuses"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters where?","choices":["stomach","skin","respiratory","Head"],"answer":"A","rationale":"The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters the stomach. The smell, taste, sight, or thought of food triggers this phase. For example, when you bring a piece of sushi to your lips, impulses from receptors in your taste buds or the nose are relayed to your brain, which returns signals that increase gastric secretion to prepare your stomach for digestion. This enhanced secretion is a conditioned reflex, meaning it occurs only if you like or want a particular food. Depression and loss of appetite can suppress the cephalic reflex. The gastric phase of secretion lasts 3 to 4 hours, and is set in motion by local neural and hormonal mechanisms triggered by the entry of food into the stomach. For example, when your sushi reaches the stomach, it creates distention that activates the.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of the earth does a compass needle align with?","choices":["molecular field","magnetic field","gravitational field","geospatial field"],"answer":"B","rationale":"You can use Earth's magnetic field to tell you where you want to go. A compass needle aligns with Earth\u2019s magnetic field. People can navigate by finding magnetic north. If you know where north is, you can figure out how to get anywhere. A compass is great for finding your way when you're out in the field!.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Parasitic chelicerates like ticks and mites have evolved what?","choices":["licking apparatuses","tunicates apparatuses","bloodsucking apparatuses","aileron apparatuses"],"answer":"C","rationale":"Most chelicerates ingest food using a preoral cavity formed by the chelicerae and pedipalps. Some chelicerates may secrete digestive enzymes to pre-digest food before ingesting it. Parasitic chelicerates like ticks and mites have evolved bloodsucking apparatuses. The nervous system in chelicerates consists of a brain and two ventral nerve cords. These animals use external fertilization as well as internal fertilization strategies for reproduction, depending upon the species and its habitat. Parental care for the young ranges from absolutely none to relatively prolonged care.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where do two tributaries come together at?","choices":["confluence","axis","stream","snake"],"answer":"A","rationale":"A tributary begins at its headwaters on one side of a divide. Two tributaries come together at a confluence.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The force exerted by the atmosphere on the earth\u2019s surface can be measured with what instrument?","choices":["anemometer","Geiger counter","mass spectrometer","barometer"],"answer":"D","rationale":"We can measure atmospheric pressure, the force exerted by the atmosphere on the earth\u2019s surface, with a barometer (Figure 9.4). A barometer is a glass tube that is closed at one end, filled with a nonvolatile liquid such as mercury, and then inverted and immersed in a container of that liquid. The atmosphere exerts pressure on the liquid outside the tube, the column of liquid exerts pressure inside the tube, and the pressure at the liquid surface is the same inside and outside the tube. The height of the liquid in the tube is therefore proportional to the pressure exerted by the atmosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the substances that the body needs for energy, building materials, and control of body processes?","choices":["liquids","tissues","nutrients","gases"],"answer":"C","rationale":"Nutrients are substances that the body needs for energy, building materials, and control of body processes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term describes the energy required to increase the surface area of a liquid by a given amount?","choices":["surface tension","elastic collision","boiling point","viscosity"],"answer":"A","rationale":"Summary Surface tension is the energy required to increase the surface area of a liquid by a given amount. The stronger the intermolecular interactions, the greater the surface tension. Surfactants are molecules, such as soaps and detergents, that reduce the surface tension of polar liquids like water. Capillary action is the phenomenon in which liquids rise up into a narrow tube called a capillary. It results whencohesive forces, the intermolecular forces in the liquid, are weaker thanadhesive forces, the attraction between a liquid and the surface of the capillary. The shape of the meniscus, the upper surface of a liquid in a tube, also reflects the balance between adhesive and cohesive forces. The viscosity of a liquid is its resistance to flow. Liquids that have strong intermolecular forces tend to have high viscosities.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the process of turning sunlight's energy into food?","choices":["glycolysis","photosynthesis","light compression","atherosclerosis"],"answer":"B","rationale":"Photosynthesis , the process of turning the energy of sunlight into \u2018\u2018food,\u2019\u2019 is divided into two basic sets of reactions, known as the light reactions and the Calvin cycle, which uses carbon dioxide. As you study the details in other concepts, refer frequently to the chemical equation of photosynthesis: 6CO 2 + 6H 2 O + Light Energy \u2192 C 6 H 12 O 6 + 6O 2 . Photosynthesis occurs in the chloroplast, an organelle specific to plant cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Because water expands when it freezes, what property of water is lower when it is in a solid state than a liquid?","choices":["mass","salinity","density","volume"],"answer":"C","rationale":"The melting point of water is 0\u00b0C. Below this temperature, water is a solid (ice). Unlike most chemical substances, water in a solid state has a lower density than water in a liquid state. This is because water expands when it freezes. Again, hydrogen bonding is the reason. Hydrogen bonds cause water molecules to line up less efficiently in ice than in liquid water. As a result, water molecules are spaced farther apart in ice, giving ice a lower density than liquid water. A substance with lower density floats on a substance with higher density. This explains why ice floats on liquid water, whereas many other solids sink to the bottom of liquid water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is released during dehydration synthesis?","choices":["water","air","photons","helium"],"answer":"A","rationale":"Dehydration Synthesis Most macromolecules are made from single subunits, or building blocks, called monomers. The monomers combine with each other using covalent bonds to form larger molecules known as polymers. In doing so, monomers release water molecules as byproducts. This type of reaction is known as dehydration synthesis, which means \u201cto put together while losing water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do plant cells have in addition to a cell wall and a large central vacuole?","choices":["plastids","DNA","chromosomes","gastropods"],"answer":"A","rationale":"Plant cells have a cell wall, a large central vacuole, and plastids such as chloroplasts.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the only animal group that evolved to live on land and then back to live in the ocean?","choices":["reptiles","birds","amphibians","mammals"],"answer":"D","rationale":"Mammals are also the only animal group that evolved to live on land and then back to live in the ocean. Whales, dolphins, and porpoises have all adapted from land-dwelling creatures to a life of swimming and reproducing in the water ( Figure below ). Whales have evolved into the largest mammals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What has large crystals because the magma began to cool slowly, then erupted?","choices":["lava","chalky","porphyry","crystalline"],"answer":"C","rationale":"This sarcophagus is housed at the Vatican Museum. The rock is the igneous extrusive rock porphyry. Porphyry has large crystals because the magma began to cool slowly, then erupted.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What must be regulated in order to maintain carbon dioxide levels and proper blood ph?","choices":["breathing rate","oxygen rate","Heart rate","blood toxin levels"],"answer":"A","rationale":"Blood pH may become unbalanced if the rate of breathing is too fast or too slow. When breathing is too fast, blood contains too little carbon dioxide and becomes too basic. When breathing is too slow, blood contains too much carbon dioxide and becomes too acidic. Clearly, to maintain proper blood pH, the rate of breathing must be regulated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cells may enter a period of rest known as what?","choices":["interkinesis","respiration","anaphase","stationary phase"],"answer":"A","rationale":"During telophase I, the spindle fiber disassembles and the nucleus reforms. The genetic material briefly uncoils back into chromatin. This is quickly followed by cytokinesis. Cells may enter a period of rest known as interkinesis or interphase II, or immediately enter meiosis II. No DNA replication occurs between meiosis I and meiosis II.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Headaches are associated with which body system?","choices":["nervous system","respiratory system","cardiovascular system","circulatory system"],"answer":"A","rationale":"We all get headaches. Headaches are a relatively minor problem associated with the nervous system. But what about more serious issues of the nervous system? As you can probably imagine, these can be extremely serious.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of volcano has a very wide base and is named because it looks like something a warrior would use?","choices":["spear volcano","plate volcano","arrow volcano","shield volcano"],"answer":"D","rationale":"Shield volcanoes look like a huge ancient warrior\u2019s shield laid down. Pictured above is Mauna Kea Volcano ( Figure above ) taken from Mauna Loa Volcano. Both volcanoes are part of the Big Island of Hawaii. A shield volcano has a very wide base. It is much flatter on the top than a composite volcano. The lava that creates shield volcanoes is relatively thin. The thin lava spreads out. This builds a large, flat volcano, layer by layer. The composition of lava at shield volcanoes is mafic. Shield volcanoes are very large. For example, the Mauna Loa Volcano has a diameter of more than 112 kilometers (70 miles). The volcano forms a significant part of the island of Hawaii. The top of nearby Mauna Kea Volcano is more than ten kilometers (6 miles) from its base on the seafloor.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Earth\u2019s magnetic field is called the what?","choices":["thermosphere","stratosphere","ionosphere","magnetosphere"],"answer":"D","rationale":"Like all magnets, Earth has a magnetic field. Earth\u2019s magnetic field is called the magnetosphere . You can see a model of the magnetosphere in the Figure below . It is a huge region that extends outward from Earth in all directions. Earth exerts magnetic force over the entire field, but the force is strongest at the poles, where lines of force converge. For an animated model of the magnetosphere, watch this video: http:\/\/www. youtube. com\/watch?v=5SXgOWYyn84 .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Global sources of inexpensive fossil fuels, particularly oil, are rapidly being what?","choices":["weakened","polluted","replenished","depleted"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the volume of air inhaled and exhaled with each breath called?","choices":["respiration volume","tidal volume","aspiration volume","lung volume"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What encloses and defines the borders of cells?","choices":["plasma membranes","cells membranes","clear membranes","artificial membranes"],"answer":"A","rationale":"CHAPTER SUMMARY 5.1 Components and Structure The modern understanding of the plasma membrane is referred to as the fluid mosaic model. The plasma membrane is composed of a bilayer of phospholipids, with their hydrophobic, fatty acid tails in contact with each other. The landscape of the membrane is studded with proteins, some of which span the membrane. Some of these proteins serve to transport materials into or out of the cell. Carbohydrates are attached to some of the proteins and lipids on the outward-facing surface of the membrane, forming complexes that function to identify the cell to other cells. The fluid nature of the membrane is due to temperature, the configuration of the fatty acid tails (some kinked by double bonds), the presence of cholesterol embedded in the membrane, and the mosaic nature of the proteins and protein-carbohydrate combinations, which are not firmly fixed in place. Plasma membranes enclose and define the borders of cells, but rather than being a static bag, they are dynamic and constantly in flux.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for a homogeneous mixture of two or more substances?","choices":["element","solution","compound","saturation"],"answer":"B","rationale":"When rocks or other substances dissolve in water, they form a solution. A solution is a homogeneous mixture of two or more substances. The particles of a solution are mixed evenly throughout it. The particles are too small to be seen or to settle out. An example of a solution is salt water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the simplest life cycle?","choices":["glycolysis","eukaryot","meiosis","haploid"],"answer":"D","rationale":"The haploid life cycle is the simplest life cycle. Organisms with this life cycle, such as many protists and some fungi and algae, spend the majority of their life cycle as a haploid cell. In fact, the zygote is the only diploid cell. The zygote immediately undergoes meiosis, producing four haploid cells, which grow into haploid multicellular organisms. These organisms produce gametes by mitosis. The gametes fuse through a process called syngamy to produce diploid zygotes which undergo meiosis, continuing the life cycle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Like mammals, birds have kidneys with juxtamedullary nephrons that specialize in conserving what?","choices":["air","blood","food","water"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the range of all possible frequencies of radiation called?","choices":["electromagnetic spectrum","particles spectrum","vibrations spectrum","Difused Spectrum"],"answer":"A","rationale":"Visible light constitutes only one of many types of electromagnetic radiation emitted from the sun and other stars. Scientists differentiate the various types of radiant energy from the sun within the electromagnetic spectrum. The electromagnetic spectrum is the range of all possible frequencies of radiation (Figure 8.11). The difference between wavelengths relates to the amount of energy carried by them.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of growth generally occurs only when a population is living under ideal conditions, yet cannot continue for very long?","choices":["logarithmic growth","exponential growth","negative growth","analogous growth"],"answer":"B","rationale":"With exponential growth, the population starts out growing slowly. As population size increases, the growth rate also increases. The larger the population becomes, the more quickly it grows. This type of growth generally occurs only when a population is living under ideal conditions. However, it can\u2019t continue for very long.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is another term for flagella?","choices":["arthropods","pseudopods","dendrites","tendrils"],"answer":"B","rationale":"Why are algae considered plant-like? The main reason is that they contain chloroplasts and produce food through photosynthesis . However, they lack many other structures of true plants. For example, algae do not have roots, stems, or leaves. Some algae also differ from plants in being motile. They may move with pseudopods or flagella. Although not plants themselves, algae were probably the ancestors of plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Because arthropod appendages are jointed, they can do what?","choices":["rotate","fly","bend","eat"],"answer":"C","rationale":"Because arthropod appendages are jointed, they can bend. This makes them flexible. Jointed appendages on the body are usually used as legs for walking or jumping. Jointed appendages on the head may be modified for other purposes. Head appendages often include upper and lower jaws. Jaws are used for eating and may also be used for defense. Sensory organs such as eyes and antennae are also found on the head. You can see some of these head appendages on the bee in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the main way that wind causes erosion?","choices":["abrasion","filtration","absorption","decomposition"],"answer":"A","rationale":"Abrasion is the main way that wind causes erosion. The next lesson explains how glaciers cause erosion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each hydrogen atom follows the octet rule with how many pairs of electrons?","choices":["eight","six","four","one"],"answer":"D","rationale":"The oxygen atom follows the octet rule with two pairs of bonding electrons and two lone pairs. Each hydrogen atom follows the octet rule with one bonding pair of electrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of acid is an organic compound that is built of small units called nucleotides?","choices":["citric acid","nucleic acid","carbolic acid","boundary acid"],"answer":"B","rationale":"A nucleic acid is an organic compound, such as DNA or RNA, that is built of small units called nucleotides . Many nucleotides bind together to form a chain called a polynucleotide . The nucleic acid DNA (deoxyribonucleic acid) consists of two polynucleotide chains. The nucleic acid RNA (ribonucleic acid) consists of just one polynucleotide chain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"At what temperatures do crystals formed by covalent molecular solids melt at?","choices":["low","hot","scorching","high"],"answer":"A","rationale":"Physical Properties of Ionic and Covalent Compounds In general, ionic and covalent compounds have different physical properties. Ionic compounds usually form hard crystalline solids that melt at rather high temperatures and are very resistant to evaporation. These properties stem from the characteristic internal structure of an ionic solid, illustrated schematically in part (a) in Figure 2.8 \"Interactions in Ionic and Covalent Solids\", which shows the three-dimensional array of alternating positive and negative ions held together by strong electrostatic attractions. In contrast, as shown in part (b) in Figure 2.8 \"Interactions in Ionic and Covalent Solids\", most covalent compounds consist of discrete molecules held together by comparatively weak intermolecular forces (the forces between molecules), even though the atoms within each molecule are held together by strong intramolecularcovalent bonds (the forces within the molecule). Covalent substances can be gases, liquids, or solids at room temperature and pressure, depending on the strength of the intermolecular interactions. Covalent molecular solids tend to form soft crystals that melt at rather low temperatures and evaporate relatively easily.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the rigid layer that is found outside the cell membrane and surrounds the cell?","choices":["cell envelope","cellular shield","cell wall","epidermis"],"answer":"C","rationale":"A cell wall is a rigid layer that is found outside the cell membrane and surrounds the cell. The cell wall contains not only cellulose and protein, but other polysaccharides as well. The cell wall provides structural support and protection. Pores in the cell wall allow water and nutrients to move into and out of the cell. The cell wall also prevents the plant cell from bursting when water enters the cell.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Who is widely known as the father of genetics?","choices":["gregor mendel","walter gehring","francis crick","james watson"],"answer":"A","rationale":"The pea plant Pisum sativum has purple and white flowers. These flowered plants are not just pretty to look at. These plants led Gregor Mendel to unlock the secrets of heredity, beginning the field of genetics. For his efforts, Mendel is widely known as the Father of Genetics, even though he knew nothing of the genetic material, DNA. The laws he developed apply to all sexually reproducing life, and are the basis for beginning to understand many human diseases.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Protozoa that cause malaria are spread by a vector, entering the blood through the bite of what insect?","choices":["housefly","wasp","mosquito","fire ant"],"answer":"C","rationale":"Protozoa that cause malaria are spread by a vector. They enter the blood through the bite of an infected mosquito. They live inside red blood cells. They cause overall body pain, fever, and fatigue. Malaria kills several million people each year. Most of the deaths occur in children.","split":"validation","source_dataset":"sciq","subject":null},{"question":"One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and what?","choices":["friction","motion","velocity","speed"],"answer":"D","rationale":"Figure 6.2 One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and speed. The wave with the shortest wavelength has the highest frequency. Amplitude is one-half the height of the wave from peak to trough.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Animals use saturated fatty acids to store what?","choices":["water","hydrogen","blood","energy"],"answer":"D","rationale":"Animals use saturated fatty acids to store energy. Plants use unsaturated fatty acids to store energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The atmospheric concentration of carbon dioxide on earth has been regulated by the concentration of what form of life?","choices":["plant","fungus","seaweed","fruit"],"answer":"A","rationale":"Homeostasis is a term that is also used when talking about the environment. For example, the atmospheric concentration of carbon dioxide on Earth has been regulated by the concentration of plant life on Earth, because plants remove more carbon dioxide from the atmosphere during the daylight hours than they emit to the atmosphere at night.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What organisms have a life cycle that includes alternation of generations?","choices":["insects","animals","fungi","plants"],"answer":"D","rationale":"All plants have a characteristic life cycle that includes alternation of generations.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are nekton animals able to do in water?","choices":["breath","move on their own, swim","lay eggs","reproduce"],"answer":"B","rationale":"Nekton are aquatic animals that can move on their own by \u201cswimming\u201d through the water. They may live in the photic or aphotic zone. They feed on plankton or other nekton. Examples of nekton include fish and shrimp.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a property of a system whose magnitude depends on only the present state of the system, not its previous history?","choices":["intensive function","laplacian","state function","extensive function"],"answer":"C","rationale":"conserved. The state of a system is a complete description of a system at a given time, including its temperature and pressure, the amount of matter it contains, its chemical composition, and the physical state of the matter. A state function is a property of a system whose magnitude depends on only the present state of the system, not its previous history. Temperature, pressure, volume, and potential energy are all state functions. The temperature of an oven, for example, is independent of however many steps it may have taken for it to reach that temperature. Similarly, the pressure in a tire is independent of how often air is pumped into the tire for it to reach that pressure, as is the final volume of air in the tire. Heat and work, on the other hand, are not state functions because they are path dependent. For example, a car sitting on the top level of a parking garage has the same potential energy whether it was lifted by a crane, set there by a helicopter, driven up, or pushed up by a group of students (). The amount of work expended to get it there, however, can differ greatly depending on the path chosen. If the students decided to carry the car to the top of the ramp, they would perform a great deal more work than if they simply pushed the car up the ramp (unless, of course, they neglected to release the parking brake, in which case the work expended would increase substantially!). The potential energy of the car is the same, however, no matter which path they choose.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Prokaryotic cells lack what key structure and other membrane-bound organelles?","choices":["epidermis","nucleus","proton","cell wall"],"answer":"B","rationale":"Prokaryotic cells lack a nucleus and other membrane-bound organelles.","split":"validation","source_dataset":"sciq","subject":null},{"question":"All of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as what?","choices":["slowed metabolism","cell ' s metabolism","genetic metabolism","particles ' s metabolism"],"answer":"B","rationale":"4.1 | Energy and Metabolism By the end of this section, you will be able to: \u2022 Explain what metabolic pathways are \u2022 State the first and second laws of thermodynamics \u2022 Explain the difference between kinetic and potential energy \u2022 Describe endergonic and exergonic reactions \u2022 Discuss how enzymes function as molecular catalysts Scientists use the term bioenergetics to describe the concept of energy flow (Figure 4.2) through living systems, such as cells. Cellular processes such as the building and breaking down of complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are spontaneous and release energy, whereas others require energy to proceed. Just as living things must continually consume food to replenish their energy supplies, cells must continually produce more energy to replenish that used by the many energy-requiring chemical reactions that constantly take place. Together, all of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as the cell\u2019s metabolism.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In genetic drift, chance fluctuations in allele frequencies over generations tend to reduce what?","choices":["biochemical variation","genetic variation","responsible variation","genetic entanglement"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What gives the order of electron filling in an atom?","choices":["Bohr's law","periodic table","orbit order","aufbau principle"],"answer":"D","rationale":"The Aufbau principle gives the order of electron filling in an atom.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs whenever an unbalanced force acts on an object?","choices":["acceleration","inertia","compression","vibration"],"answer":"A","rationale":"Whenever an object speeds up, slows down, or changes direction, it accelerates. Acceleration occurs whenever an unbalanced force acts on an object. Two factors affect the acceleration of an object: the net force acting on the object and the object\u2019s mass. Newton\u2019s second law of motion describes how force and mass affect acceleration. The law states that the acceleration of an object equals the net force acting on the object divided by the object\u2019s mass. This can be represented by the equation:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are large collections of millions or billions of stars called?","choices":["orbits","galaxies","universe","fragments"],"answer":"B","rationale":"Galaxies are collections of millions to many billions of stars.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the developmental process of gastropods called?","choices":["occlusion","regeneration","torsion","modulation"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Name one unit used to measure pressure.","choices":["watt","decibel","torr","meter"],"answer":"C","rationale":"Pressures are given in a multitude of units. We've already discussed Pascals, and we know that another unit for pressure is the atmosphere (1 atm = 101.3 x 10 5 Pa). The third commonly used pressure unit is the torr (symbol: Torr). 760 torr is 1 atm, but 1 torr is also the increase in pressure necessary to cause liquid mercury to rise by 1 mm. For that reason, torr is also commonly referred to as \"millimeters mercury. \" Another pressure unit commonly used in our everyday world is psi, or pounds per square inch, though neither psi nor torr are SI units.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Eggs and sperm are not somatic cells but instead what kind of cells?","choices":["Sickness","pollen","germ","toxins"],"answer":"C","rationale":"So far in this chapter, you have read numerous times of the importance and prevalence of cell division. While there are a few cells in the body that do not undergo cell division (such as gametes, red blood cells, most neurons, and some muscle cells), most somatic cells divide regularly. A somatic cell is a general term for a body cell, and all human cells, except for the cells that produce eggs and sperm (which are referred to as germ cells), are somatic cells. Somatic cells contain two copies of each of their chromosomes (one copy received from each parent). A homologous pair of chromosomes is the two copies of a single chromosome found in each somatic cell. The human is a diploid organism, having 23 homologous pairs of chromosomes in each of the somatic cells. The condition of having pairs of chromosomes is known as diploidy. Cells in the body replace themselves over the lifetime of a person. For example, the cells lining the gastrointestinal tract must be frequently replaced when constantly \u201cworn off\u201d by the movement of food through the gut. But what triggers a cell to divide, and how does it prepare for and complete cell division? The cell cycle is the sequence of events in the life of the cell from the moment it is created at the end of a previous cycle of cell division until it then divides itself, generating two new cells.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Regular checkups with what type of specialist can detect skin cancers early?","choices":["internist","nephrologist","endocrinologist","dermatologist"],"answer":"D","rationale":"Regular checkups with a dermatologist can detect skin cancers early. Why is early detection important?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Receptors for what sense are located within sensory hairs on the feet of insects, as well as in mouthparts?","choices":["touch","smell","sight","taste"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Where does the stored energy in fossil fuels originally come from, before it changed forms several times?","choices":["the Moon","Earth's core","decomposers","the sun"],"answer":"D","rationale":"Fossil fuels contain stored chemical energy that came originally from the sun. Ancient plants changed energy in sunlight to stored chemical energy in food, which was eaten by other organisms. After the plants and other organisms died, their remains gradually changed to fossil fuels as they were pressed beneath layers of sediments. Petroleum and natural gas formed from marine organisms and are often found together. Coal formed from giant tree ferns and other swamp plants.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A prokaryote is a simple, mostly single-celled organism that lacks what key organelle?","choices":["golgi apparatus","nucleus","chloroplast","ribosome"],"answer":"B","rationale":"are found; 3) DNA, the genetic material of the cell; and 4) ribosomes, which synthesize proteins. However, prokaryotes differ from eukaryotic cells in several ways. A prokaryote is a simple, mostly single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle. We will shortly come to see that this is significantly different in eukaryotes. Prokaryotic DNA is found in a central part of the cell: the nucleoid (Figure 4.5).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Increasing the surface area of solid reactants increases what rate?","choices":["metabolism","breathing","fusion","reaction"],"answer":"D","rationale":"When a solid substance is involved in a chemical reaction, only the matter at the surface of the solid is exposed to other reactants. If a solid has more surface area, more of it is exposed and able to react. Therefore, increasing the surface area of solid reactants increases the reaction rate. Look at the hammer and nails pictured in the Figure below . Both are made of iron and will rust when the iron combines with oxygen in the air. However, the nails have a greater surface area, so they will rust faster.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Epithelial cells are found in what body organ?","choices":["lungs","liver","brain","skin"],"answer":"D","rationale":"DNA Replication In order for an organism to grow, develop, and maintain its health, cells must reproduce themselves by dividing to produce two new daughter cells, each with the full complement of DNA as found in the original cell. Billions of new cells are produced in an adult human every day. Only very few cell types in the body do not divide, including nerve cells, skeletal muscle fibers, and cardiac muscle cells. The division time of different cell types varies. Epithelial cells of the skin and gastrointestinal lining, for instance, divide very frequently to replace those that are constantly being rubbed off of the surface by friction. A DNA molecule is made of two strands that \u201ccomplement\u201d each other in the sense that the molecules that compose the strands fit together and bind to each other, creating a double-stranded molecule that looks much like a long, twisted ladder. Each side rail of the DNA ladder is composed of alternating sugar and phosphate groups (Figure 3.23). The two sides of the.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What's the name for an organic compound in which halogen atoms are substituted for hydrogen in a hydrocarbon?","choices":["glucose","alkyl halide","alcohol","sodium halide"],"answer":"B","rationale":"An alkyl halide is an organic compound in which one or more halogen atoms are substituted for one or more hydrogen atoms in a hydrocarbon. The general formulas for organic molecules with functional groups use the letter R to stand for the rest of the molecule outside of the functional group. Because there are four possible halogen atoms (fluorine, chlorine, bromine, or iodine) that can act as the functional group, we use the general formula R\u2212X to represent an alkyl halide. The rules for naming simple alkyl halides are listed below.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The trachea and bronchi are made of incomplete rings of this?","choices":["membrane","collagen","ligaments","cartilage"],"answer":"D","rationale":"Figure 39.8 The trachea and bronchi are made of incomplete rings of cartilage. (credit: modification of work by Gray's Anatomy).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we call cyclones that form in tropical latitudes?","choices":["twister","eruptions","disturbances","hurricanes"],"answer":"D","rationale":"Hurricanes are cyclones that form in tropical latitudes. They are called tropical cyclones.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which amino acid do organisms incorporate into their proteins?","choices":["histone","peptide","arginine","glutamate"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms?","choices":["sediment","coal","fossil","trilobites"],"answer":"C","rationale":"Oil, or petroleum, is one of several fossil fuels . Fossil fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms. In addition to oil, they include coal and natural gas. Fossil fuels provide most of the energy used in the world today. They are burned in power plants to produce electrical energy, and they also fuel cars, heat homes, and supply energy for many other purposes. You can see some ways they are used in the Figure below . For a more detailed introduction to fossil fuels, go to this URL: http:\/\/www. ecokids. ca\/pub\/eco_info\/topics\/energy\/ecostats\/index. cfm.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the cartilaginous structure that extends from the pharynx to the primary bronchi?","choices":["cricoid","larynx","trachea","sternohyoid"],"answer":"C","rationale":"Chapter 39 1 Figure 39.7 B 3 Figure 39.20 The blood pH will drop and hemoglobin affinity for oxygen will decrease. 4 A 6 B 8 D 10 B 12 D 14 C 16 The main bronchus is the conduit in the lung that funnels air to the airways where gas exchange occurs. The main bronchus attaches the lungs to the very end of the trachea where it bifurcates. The trachea is the cartilaginous structure that extends from the pharynx to the primary bronchi. It serves to funnel air to the lungs. The alveoli are the sites of gas exchange; they are located at the terminal regions of the lung and are attached to the respiratory bronchioles. The acinus is the structure in the lung where gas exchange occurs. 18 FEV1\/FVC measures the forced expiratory volume in one second in relation to the total forced vital capacity (the total amount of air that is exhaled from the lung from a maximal inhalation). This ratio changes with alterations in lung function that arise from diseases such as fibrosis, asthma, and COPD. 20 Oxygen moves from the lung to the bloodstream to the tissues according to the pressure gradient. This is measured as the partial pressure of oxygen. If the amount of oxygen drops in the inspired air, there would be reduced partial pressure. This would decrease the driving force that moves the oxygen into the blood and into the tissues. P O is also reduced at high elevations: P O at high elevations is lower than 2.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Excess dietary fat is stored as triglycerides in the body. what type of tissue is used to store the triglycerides?","choices":["adipose","metabolic","muscle","connective"],"answer":"A","rationale":"inside these cells, glucose is immediately converted into glucose-6-phosphate. By doing this, a concentration gradient is established where glucose levels are higher in the blood than in the cells. This allows for glucose to continue moving from the blood to the cells where it is needed. Insulin also stimulates the storage of glucose as glycogen in the liver and muscle cells where it can be used for later energy needs of the body. Insulin also promotes the synthesis of protein in muscle. As you will see, muscle protein can be catabolized and used as fuel in times of starvation. If energy is exerted shortly after eating, the dietary fats and sugars that were just ingested will be processed and used immediately for energy. If not, the excess glucose is stored as glycogen in the liver and muscle cells, or as fat in adipose tissue; excess dietary fat is also stored as triglycerides in adipose tissues. Figure 24.21 summarizes the metabolic processes occurring in the body during the absorptive state.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call winds that occur in belts that go all around the planet?","choices":["rotational winds","solar winds","global winds","gravitational winds"],"answer":"C","rationale":"Global winds are winds that occur in belts that go all around the planet. You can see them in Figure below . Like local winds, global winds are caused by unequal heating of the atmosphere.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What property is a property that depends on the amount of matter in a sample?","choices":["non-exact","relative","provided","extensive"],"answer":"D","rationale":"Some properties of matter depend on the size of the sample, while some do not. An extensive property is a property that depends on the amount of matter in a sample. The mass of an object is a measure of the amount of matter that an object contains. A small sample of a certain type of matter will have a small mass, while a larger sample will have a greater mass. Another extensive property is volume . The volume of an object is a measure of the space that is occupied by that object.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The legend explains features and symbols on?","choices":["compass","map","earth","telescopes"],"answer":"B","rationale":"Look for the legend on the top left side of the map. The legend explains other features and symbols on the map.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Organic acids such as acetic acid all contain a functional group called what?","choices":["protein","ester group","carboxyl group","glycoprotein group"],"answer":"C","rationale":"Organic acids such as acetic acid all contain a functional group called a carboxyl group .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which is the only organ system in humans that differs greatly between males and females?","choices":["digestive system","immune system","neural system","reproductive system"],"answer":"D","rationale":"Dogs have puppies. Cats have kittens. All organisms reproduce, obviously including humans. Like other mammals, humans have a body system that controls reproduction. It is called the reproductive system . It is the only human body system that is very different in males and females. The male and female reproductive systems have different organs and different functions.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the what membrane?","choices":["cutaneous","tympanic","serous","mucous"],"answer":"B","rationale":"Figure 36.13 Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the tympanic membrane. The middle ear contains three bones called ossicles that transfer the sound wave to the oval window, the exterior boundary of the inner ear. The organ of Corti, which is the organ of sound transduction, lies inside the cochlea. (credit: modification of work by Lars Chittka, Axel Brockmann).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the most common cause of hearing loss?","choices":["infection","loud sounds","quiet sounds","birth defect"],"answer":"B","rationale":"Many activities expose people to dangerously loud sounds that can cause hearing loss.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some products contain iron filings that will react with air to release what type of energy?","choices":["thermal","mechanical","spectral","physical"],"answer":"A","rationale":"Hikers, campers, and other outdoor folks take advantage of chemical reactions to keep their hands warm. Small containers of chemicals can undergo reaction to generate heat that can be used to avoid frostbite. Some products contain iron filings that will react with air to release thermal energy. These types of warmer cannot be reused. Other systems rely on heat being released when certain chemicals crystallize. If the warmer is placed in very hot water after use, the system can be regenerated.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Mutations in what type of regulatory gene can cause misplacement of structures in an animal?","choices":["homeotic","diploid","dichotic","myogenic"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"By what processes do rivers create floodplains?","choices":["deposition and sedimentation","erosion and deposition","depletion and erosion","thrust and deposition"],"answer":"B","rationale":"Erosion and deposition by slow-flowing rivers creates broad floodplains and meanders.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What biological agents that infect living hosts contain dna, yet lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes?","choices":["viruses","bacteria","worms","parasites"],"answer":"A","rationale":"Viruses contain DNA but not much else. They lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes. Therefore, viruses are not cells, but are they alive? All living things not only have cells; they are also capable of reproduction. Viruses cannot reproduce by themselves. Instead, they infect living hosts, and use the hosts\u2019 cells to make copies of their own DNA. Viruses also do not have their own metabolism or maintain homeostasis. For these reasons, most scientists do not consider viruses to be living things.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An extensive property is a property that depends on the amount of what in a sample?","choices":["water","plasma","matter","space"],"answer":"C","rationale":"An extensive property is a property that depends on the amount of matter in a sample.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A wheel with a rope wrapped around it, hanging over a building, is an example of what type of machine?","choices":["pedal","propeller","pulley","simple machine"],"answer":"C","rationale":"This rusty iron wheel has a rope wrapped around it. The wheel and rope hang over a building. Together they make up a type of machine called a pulley.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Early types of what animals were the first vertebrates that moved onto land and have true lungs, although they had to return to the water to reproduce?","choices":["birds","mammals","amphibians","reptiles"],"answer":"C","rationale":"The first vertebrates moved onto land about 365 million years ago. They were early amphibians. They were the first animals to have true lungs and limbs for life on land. However, they still had to return to the water to reproduce. That\u2019s because their eggs lacked a waterproof covering and would dry out on land.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Many heterocyclic amines occur naturally in what?","choices":["gases","plants","animals","nuclei"],"answer":"B","rationale":"nucleic acids, which in turn compose the genetic material of cells and direct protein synthesis. (For more information about nucleic acids, see Chapter 19 \"Nucleic Acids\". ) Many heterocyclic amines occur naturally in plants. Like other amines, these compounds are basic. Such a compound is an alkaloid, a name that means \u201clike alkalis. \u201d Many alkaloids are physiologically active, including the familiar drugs caffeine, nicotine, and cocaine.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do wind turbines change the kinetic energy of the wind into?","choices":["available energy","electrical energy","transportable energy","potential energy"],"answer":"B","rationale":"Wind is moving air, so it has kinetic energy that can do work. Remember the wind turbines that opened this chapter? Wind turbines change the kinetic energy of the wind to electrical energy. Only certain areas of the world get enough steady wind to produce much electricity. Many people also think that wind turbines are noisy and unattractive in the landscape.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Population growth depends on birth rates and death rates, as well as what?","choices":["industrialization","marriage","migration","communication"],"answer":"C","rationale":"Population growth rate depends on birth rates and death rates, as well as migration. First, we will consider the effects of birth and death rates. You can predict the growth rate by using this simple equation: growth rate = birth rate \u2013 death rate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The exchange of heat stops once what property of equilibrium between the pan and the water is achieved?","choices":["thermal","density","motion","viscosity"],"answer":"A","rationale":"of 150\u00baC . Assume that the pan is placed on an insulated pad and that a negligible amount of water boils off. What is the temperature when the water and pan reach thermal equilibrium a short time later? Strategy The pan is placed on an insulated pad so that little heat transfer occurs with the surroundings. Originally the pan and water are not in thermal equilibrium: the pan is at a higher temperature than the water. Heat transfer then restores thermal equilibrium once the water and pan are in contact. Because heat transfer between the pan and water takes place rapidly, the mass of evaporated water is negligible and the magnitude of the heat lost by the pan is equal to the heat gained by the water. The exchange of heat stops once a thermal equilibrium between the pan and the water is achieved. The heat exchange can be written as \u2223 Q hot \u2223 = Q cold .","split":"validation","source_dataset":"sciq","subject":null},{"question":"If the area to which a force is applied is smaller then the pressure will be?","choices":["lower","the same","greater","equal"],"answer":"C","rationale":"Pressure shows how concentrated the force is on a given area. The smaller the area to which force is applied, the greater the pressure is. Think about pressing a pushpin, like the one in the Figure below , into a bulletin board. You apply force with your thumb to the broad head of the pushpin. However, the force that the pushpin applies to the bulletin board acts only over the tiny point of the pin. This is a much smaller area, so the pressure the point applies to the bulletin board is much greater than the pressure you apply with your thumb. As a result, the pin penetrates the bulletin board with ease.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call the preserved remains or traces of organisms that lived in the past?","choices":["skulls","fossils","decomposition","corals"],"answer":"B","rationale":"Fossils are preserved remains or traces of organisms that lived in the past. Most preserved remains are hard parts, such as teeth, bones, or shells. Hard parts are less likely to be destroyed before they can become fossils. Even so, a very tiny percentage of living things become fossils. These types of fossils are called body fossils ( Figure below , Figure below , and Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What process do single cell organisms use to remove waste and get nutrients into their cell?","choices":["convection","diffusion","Measured","filtration"],"answer":"B","rationale":"over a specific distance and limits the size that an individual cell can attain. If a cell is a single-celled microorganism, such as an amoeba, it can satisfy all of its nutrient and waste needs through diffusion. If the cell is too large, then diffusion is ineffective and the center of the cell does not receive adequate nutrients nor is it able to effectively dispel its waste. An important concept in understanding how efficient diffusion is as a means of transport is the surface to volume ratio. Recall that any three-dimensional object has a surface area and volume; the ratio of these two quantities is the surfaceto-volume ratio. Consider a cell shaped like a perfect sphere: it has a surface area of 4\u03c0r2, and a volume of (4\/3)\u03c0r3. The surface-to-volume ratio of a sphere is 3\/r; as the cell gets bigger, its surface to volume ratio decreases, making diffusion less efficient. The larger the size of the sphere, or animal, the less surface area for diffusion it possesses. The solution to producing larger organisms is for them to become multicellular. Specialization occurs in complex organisms, allowing cells to become more efficient at doing fewer tasks. For example, circulatory systems bring nutrients and remove waste, while respiratory systems provide oxygen for the cells and remove carbon dioxide from them. Other organ systems have developed further specialization of cells and tissues and efficiently control body functions. Moreover, surface-tovolume ratio applies to other areas of animal development, such as the relationship between muscle mass and cross-sectional surface area in supporting skeletons, and in the relationship between muscle mass and the generation of dissipation of heat.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Trees release what gas as a byproduct of photosynthesis, thereby facilitating human respiration?","choices":["methane","nitrogen","oxygen","carbon dioxide"],"answer":"C","rationale":"Recall that trees release oxygen as a byproduct of photosynthesis. And you need oxygen to breathe. Do you know why? So your cells can perform cellular respiration and make ATP.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of muscle cells have a single nucleus and are spindle-shaped?","choices":["skeletal muscle","cardiac muscle","liquid muscle","smooth muscle"],"answer":"D","rationale":"10.8 Smooth Muscle Smooth muscle is found throughout the body around various organs and tracts. Smooth muscle cells have a single nucleus, and are spindle-shaped. Smooth muscle cells can undergo hyperplasia, mitotically dividing to produce new cells. The smooth cells are nonstriated, but their sarcoplasm is filled with actin and myosin, along with dense bodies in the sarcolemma to anchor the thin filaments and a network of intermediate filaments involved in pulling the sarcolemma toward the fiber\u2019s middle, shortening it in the process. Ca++ ions trigger contraction when they are released from SR and enter through opened voltage-gated calcium channels. Smooth muscle contraction is initiated when the Ca++ binds to intracellular calmodulin, which then activates an enzyme called myosin kinase that phosphorylates myosin heads so they can form the cross-bridges with actin and then pull on the thin filaments. Smooth muscle can be stimulated by pacesetter cells, by the autonomic nervous system, by hormones, spontaneously, or by stretching. The fibers in some smooth muscle have latch-bridges, crossbridges that cycle slowly without the need for ATP; these muscles can maintain low-level contractions for long periods. Single-unit smooth muscle tissue contains gap junctions to synchronize membrane depolarization and contractions so that the muscle contracts as a single unit. Single-unit smooth muscle in the walls of the viscera, called visceral muscle, has a stress-relaxation response that permits muscle to stretch, contract, and relax as the organ expands. Multiunit smooth muscle cells do not possess gap junctions, and contraction does not spread from one cell to the next.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The cortical reaction has begun, initiating events that ensure that only one sperm nucleus enters where?","choices":["the sperm","the spore","the heart","the egg"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do the process of moving air into and out of the lungs better known as?","choices":["breathing","photosynthesis","consuming","bleeding"],"answer":"A","rationale":"Breathing is the process of moving air into and out of the lungs. The process depends on a muscle called the diaphragm. This is a large, sheet-like muscle below the lungs. You can see it in Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which kind of rocks contain felsic minerals, typically contain aluminum and sodium and are high in silica?","choices":["felsic igneous","sedimentary","igneous","metamorphic"],"answer":"A","rationale":"Felsic igneous rocks contain felsic minerals. They typically contain aluminum and sodium; they are high in silica. Quartz and potassium feldspar are felsic minerals. Minerals and rocks with a composition in between mafic and felsic are called intermediate.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are trees that lose their leaves during winter called?","choices":["coniferous","deciduous","fruits","fungus"],"answer":"B","rationale":"trees that lose their leaves once a year.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Other than gametes, normal human cells have a total of how many chromosomes per cell?","choices":["23","36","46","33"],"answer":"C","rationale":"Human Chromosomes. Human chromosomes are shown here arranged by size. Chromosome 1 is the largest, and chromosome 22 is the smallest. All normal human cells (except gametes) have two of each chromosome, for a total of 46 chromosomes per cell. Only one of each pair is shown here.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the simplest type of carbon-based compounds?","choices":["fossil fuels","inorganic compounds","hydrocarbons","organic compounds"],"answer":"C","rationale":"Hydrocarbons are compounds that contain only carbon and hydrogen. Hydrocarbons are the simplest type of carbon-based compounds, but they can vary greatly in size. The smallest hydrocarbons have just one or two carbon atoms. The largest hydrocarbons may have thousands of carbon atoms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Gametogenesis, the production of sperm and eggs, takes place through the process of this?","choices":["meiosis","gametes","mutations","osmosis"],"answer":"A","rationale":"Gametogenesis (Spermatogenesis and Oogenesis) Gametogenesis, the production of sperm and eggs, takes place through the process of meiosis. During meiosis, two cell divisions separate the paired chromosomes in the nucleus and then separate the chromatids that were made during an earlier stage of the cell\u2019s life cycle. Meiosis produces haploid cells with half of each pair of chromosomes normally found in diploid cells. The production of sperm is called spermatogenesis and the production of eggs is called oogenesis. Spermatogenesis.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the name of the roundworms digestive organ?","choices":["stomach","tube","gut","intestine"],"answer":"C","rationale":"A roundworm has a complete digestive system, which includes both a mouth and an anus. This is a significant difference from the incomplete digestive system of flatworms. The roundworm digestive system also include a large digestive organ known as the gut. Digestive enzymes that start to break down food are produced here. There is no stomach, but there is an intestine which produces enzymes that help absorb nutrients. The last portion of the intestine forms a rectum, which expels waste through the anus.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Oxides contain one or two metal elements combined with what?","choices":["nitrogen","ethanol","carbon","oxygen"],"answer":"D","rationale":"Earth\u2019s crust contains a lot of oxygen. The oxygen combines with many other elements to create oxide minerals. Oxides contain one or two metal elements combined with oxygen. Oxides are different from silicates because they do not contain silicon. Many important metals are found as oxides. For example, hematite and magnetite are both oxides that contain iron. Hematite (Fe 2 O 3 ) has a ratio of two iron atoms to three oxygen atoms. Magnetite (Fe 3 O 4 ) has a ratio of three iron atoms to four oxygen atoms. Notice that the word \u201cmagnetite\u201d contains the word \u201cmagnet\u201d. Magnetite is a magnetic mineral.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What combine the spinal sensory and motor components with a sensory input that directly generates a motor response?","choices":["tissues","senses","reflexes","shocks"],"answer":"C","rationale":"Reflexes Reflexes combine the spinal sensory and motor components with a sensory input that directly generates a motor response. The reflexes that are tested in the neurological exam are classified into two groups. A deep tendon reflex is commonly known as a stretch reflex, and is elicited by a strong tap to a tendon, such as in the knee-jerk reflex. A superficial reflex is elicited through gentle stimulation of the skin and causes contraction of the associated muscles. For the arm, the common reflexes to test are of the biceps, brachioradialis, triceps, and flexors for the digits. For the leg, the knee-jerk reflex of the quadriceps is common, as is the ankle reflex for the gastrocnemius and soleus. The tendon at the insertion for each of these muscles is struck with a rubber mallet. The muscle is quickly stretched, resulting in activation of the muscle spindle that sends a signal into the spinal cord through the dorsal root. The fiber synapses directly on the ventral horn motor neuron that activates the muscle, causing contraction. The reflexes are physiologically useful for stability. If a.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of evolution happens when two species evolve the same traits?","choices":["associated","convergent","multiplicative","divergent"],"answer":"B","rationale":"Sometimes two species evolve the same traits. It happens because they live in similar habitats. This is called convergent evolution . Caribbean Anoles demonstrate this as well.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which way does an electric charge always move from?","choices":["higher to lower","low to high","like to like","diagonally"],"answer":"A","rationale":"An electric charge flows when it has electric potential energy due to its position in an electric field. An electric charge always moves spontaneously from a position of higher to lower potential energy.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the principal blood vessel through which blood leaves the heart in order to circulate around the body?","choices":["the superior vena cava","the pulmonary vein","the pulmonary artery","aorta"],"answer":"D","rationale":"Example 12.3 Calculating Flow Speed and Vessel Diameter: Branching in the Cardiovascular System The aorta is the principal blood vessel through which blood leaves the heart in order to circulate around the body. (a) Calculate the average speed of the blood in the aorta if the flow rate is 5.0 L\/min. The aorta has a radius of 10 mm. (b) Blood also flows through smaller blood vessels known as capillaries. When the rate of blood flow in the aorta is 5.0 L\/min, the speed of blood in the capillaries is about 0.33 mm\/s. Given that the average diameter of a capillary is 8.0 \u00b5m , calculate the number of capillaries in the blood circulatory system. Strategy We can use.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What increases when a muscle like a biceps is extended?","choices":["momentum","speed","force","weight"],"answer":"C","rationale":"In the above example of the biceps muscle, the angle between the forearm and upper arm is 90\u00b0. If this angle changes, the force exerted by the biceps muscle also changes. In addition, the length of the biceps muscle changes. The force the biceps muscle can exert depends upon its length; it is smaller when it is shorter than when it is stretched. Very large forces are also created in the joints. In the previous example, the downward force.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Hot magma beneath the surface mixes with water and forms what?","choices":["lava","hydrocarbons","liquids","gas"],"answer":"D","rationale":"An explosive eruption produces huge clouds of volcanic ash. Chunks of the volcano fly high into the atmosphere. Explosive eruptions can be 10,000 times as powerful as an atomic bomb ( Figure below ). Hot magma beneath the surface mixes with water. This forms gases. The gas pressure grows until it must be released. The volcano erupts in an enormous explosion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The olfactory receptor neurons are located in a small region within what cavity?","choices":["exterior nasal","posterior nasal","inferior nasal","superior nasal"],"answer":"D","rationale":"Olfaction (Smell) Like taste, the sense of smell, or olfaction, is also responsive to chemical stimuli. The olfactory receptor neurons are located in a small region within the superior nasal cavity (Figure 14.4). This region is referred to as the olfactory epithelium and contains bipolar sensory neurons. Each olfactory sensory neuron has dendrites that extend from the apical surface of the epithelium into the mucus lining the cavity. As airborne molecules are inhaled through the nose, they pass over the olfactory epithelial region and dissolve into the mucus. These odorant molecules bind to proteins that keep them dissolved in the mucus and help transport them to the olfactory dendrites. The odorant\u2013protein complex binds to a receptor protein within the cell membrane of an olfactory dendrite. These receptors are G protein\u2013coupled, and will produce a graded membrane potential in the olfactory neurons. The axon of an olfactory neuron extends from the basal surface of the epithelium, through an olfactory foramen in the cribriform plate of the ethmoid bone, and into the brain. The group of axons called the olfactory tract connect to the olfactory bulb on the ventral surface of the frontal lobe. From there, the axons split to travel to several brain regions. Some.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Single bonds between atoms are always what?","choices":["analogue bonds","genetic bonds","rna bonds","sigma bonds"],"answer":"D","rationale":"In general, single bonds between atoms are always sigma bonds. Double bonds are comprised of one sigma and one pi bond. Triple bonds are comprised of one sigma bond and two pi bonds.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of attraction does electrical force have?","choices":["similar","positive","neutral","negative"],"answer":"D","rationale":"The electrical force is a vector quantity that is positive in repulsion and negative in attraction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"At what temperatures do alkanes with more carbon atoms boil?","choices":["heavier temperatures","farther temperatures","lower temperatures","higher temperatures"],"answer":"D","rationale":"Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in \u2013 ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane with two carbon atoms. The chemical formulas and properties of methane, ethane, and other small alkanes are listed in the Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally boil and melt at higher temperatures.","split":"validation","source_dataset":"sciq","subject":null},{"question":"If the tunica externa did not hold a vessel in place, any movement would likely result in disruption of what?","choices":["heart beat","pulse","blood flow","respiration"],"answer":"C","rationale":"Tunica Externa The outer tunic, the tunica externa (also called the tunica adventitia), is a substantial sheath of connective tissue composed primarily of collagenous fibers. Some bands of elastic fibers are found here as well. The tunica externa in veins also contains groups of smooth muscle fibers. This is normally the thickest tunic in veins and may be thicker than the tunica media in some larger arteries. The outer layers of the tunica externa are not distinct but rather blend with the surrounding connective tissue outside the vessel, helping to hold the vessel in relative position. If you are able to palpate some of the superficial veins on your upper limbs and try to move them, you will find that the tunica externa prevents this. If the tunica externa did not hold the vessel in place, any movement would likely result in disruption of blood flow.","split":"validation","source_dataset":"sciq","subject":null},{"question":"One common way to remove phosphates from water is by the addition of what?","choices":["calcium hydroxide","nitrous oxide","acetic acid","isotopes"],"answer":"A","rationale":"One common way to remove phosphates from water is by the addition of calcium hydroxide, known as lime, Ca(OH)2. The lime is converted into calcium carbonate, a strong base, in the water. As the water is made more basic, the calcium ions react with phosphate ions to produce hydroxylapatite, Ca5(PO4)3(OH), which then precipitates out of the solution:.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Before going into hibernation bears eat constantly for what reason?","choices":["Decrease body fat","Decrease body protein","increase body fat","Increase body protein"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two elements make up about 99 percent of the air?","choices":["nitrogen and oxygen","helium and boron","phosphorus and oxygen","nitrogen and phosphorus"],"answer":"A","rationale":"Nitrogen and oxygen make up about 99 percent of the air. Argon and carbon dioxide make up much of the rest. The air also contains water vapor. The amount of water vapor varies from place to place.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The different types of nuclei are referred to as what?","choices":["rhizomes","atoms","nuclides","organelles"],"answer":"C","rationale":"Although the hydrogen nucleus consists of a single proton, the nuclei of all other elements contain both neutrons and protons. The different types of nuclei are referred to as nuclides . The number of protons in a nucleus is called the atomic number and is designated by the symbol . The total number of nucleons, neutrons and protons, is designated by the symbol and is called the mass number . A nuclide with 7 protons and 8 neutrons thus has and . The number of neutrons, , is . To specify a given nuclide, we need give only and . These can be shown in a complete nuclear symbol which takes the form.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What measure is the total mass of organisms at a trophic level?","choices":["detritus","phosphorus","biomass","atomic mass"],"answer":"C","rationale":"Biomass is the total mass of organisms at a trophic level. With less energy at higher trophic levels, there are usually fewer organisms as well. This is also represented in the pyramid in Figure above . Organisms tend to be larger in size at higher trophic levels. However, their smaller numbers result in less biomass.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What has the least amount of energy in an atom?","choices":["crystals","electrons","rings","protons"],"answer":"B","rationale":"The model in the Figure below shows the first four energy levels of an atom. Electrons in energy level I (also called energy level K) have the least amount of energy. As you go farther from the nucleus, electrons at higher levels have more energy, and their energy increases by a fixed, discrete amount. Electrons can jump from a lower to the next higher energy level if they absorb this amount of energy. Conversely, if electrons jump from a higher to a lower energy level, they give off energy, often in the form of light. This explains the fireworks pictured above. When the fireworks explode, electrons gain energy and jump to higher energy levels. When they jump back to their original energy levels, they release the energy as light. Different atoms have different arrangements of electrons, so they give off light of different colors. You can see an animation of electrons jumping from one energy level to another at this URL: http:\/\/cas. sdss. org\/dr6\/en\/proj\/advanced\/spectraltypes\/energylevels. asp .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the visible surface of the sun called?","choices":["stratosphere","photosphere","ionosphere","chronosphere"],"answer":"B","rationale":"The photosphere is the visible surface of the Sun ( Figure below ). It's the part that we see shining. Surprisingly, the photosphere is also one of the coolest layers of the Sun. It is only about 6,000\u00b0C.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call organisms that store chemical energy in carbohydrate food molecules they produce themselves?","choices":["heterotrophs","autotrophs","omnivores","plants"],"answer":"B","rationale":"Autotrophs, shown in the Figure below , store chemical energy in carbohydrate food molecules they produce themselves. Food is chemical energy stored in organic molecules. Food provides both the energy to do work and the carbon to build the organic structures from cells to organisms. Because most autotrophs transform sunlight to make or synthesize food, we call the process they use photosynthesis . The food produced via this process is glucose. Only three groups of organisms - plants, algae, and some bacteria - are capable of this life-giving energy transformation. Autotrophs make food for their own use, but they make enough to support other life as well. Almost all other organisms depend absolutely on these three groups for the food they produce. The producers , as autotrophs are also known, begin food chains which feed all life. Food chains will be discussed in the Ecology concepts.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which condition is the only autosomal trisomy where an affected individual may survive to adulthood?","choices":["dwarfism","progeria","down syndrome","type 1 diabetes"],"answer":"C","rationale":"One of the most common chromosome abnormalities is Down syndrome , due to nondisjunction of chromosome 21 resulting in an extra complete chromosome 21, or part of chromosome 21 ( Figure below ). Down syndrome is the only autosomal trisomy where an affected individual may survive to adulthood. Individuals with Down syndrome often have some degree of mental retardation, some impairment of physical growth, and a specific facial appearance. With proper assistance, individuals with Down syndrome can become successful, contributing members of society. The incidence of Down syndrome increases with maternal age. The risk of having a child with Down syndrome is significantly higher among women age 35 and older.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when a population reaches the carrying capacity?","choices":["impact stops","growth stops","core stops","growth increases"],"answer":"B","rationale":"A population can\u2019t keep growing bigger and bigger forever. Sooner or later, it will run out of things it needs. For a given species, there is a maximum population that can be supported by the environment. This maximum is called the carrying capacity . When a population gets close to the carrying capacity, it usually grows more slowly. You can see this in Figure below . When the population reaches the carrying capacity, it stops growing.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the form of logical thinking that uses related observations to arrive at a general conclusion called?","choices":["inductive reasoning","theory reasoning","hypthetical thinking","deductive logic"],"answer":"A","rationale":"There is no complete agreement when it comes to defining what the natural sciences include. For some experts, the natural sciences are astronomy, biology, chemistry, earth science, and physics. Other scholars choose to divide natural sciences into life sciences, which study living things and include biology, and physical sciences, which study nonliving matter and include astronomy, physics, and chemistry. Some disciplines such as biophysics and biochemistry build on two sciences and are interdisciplinary. Scientific Inquiry One thing is common to all forms of science: an ultimate goal \u201cto know. \u201d Curiosity and inquiry are the driving forces for the development of science. Scientists seek to understand the world and the way it operates. Two methods of logical thinking are used: inductive reasoning and deductive reasoning. Inductive reasoning is a form of logical thinking that uses related observations to arrive at a general conclusion. This type of reasoning is common in descriptive science. A life scientist such as a biologist makes observations and records them.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Carbon can form single, double, or triple what with other carbon atoms","choices":["phenotype bonds","covalent bonds","ionic bonds","electron bonds"],"answer":"B","rationale":"Carbon can form single, double, or triple covalent bonds with other carbon atoms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Wind or water that travels toward the poles from the equator curves in which direction?","choices":["upward","east","west","downward"],"answer":"B","rationale":"As wind or an ocean current moves, the Earth spins underneath it. Wind or water that travels toward the poles from the Equator curves to the east. Wind or water that travels toward the Equator from the poles curves to the west. The Coriolis effect bends the direction of surface currents to the right in the Northern Hemisphere. The currents curve left in the Southern Hemisphere ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is defined as the ability to cause changes in matter?","choices":["transcription","pressure","fuel","energy"],"answer":"D","rationale":"The human ear is pictured below ( Figure below ). As you read about it, trace the path of sound waves through the ear. Assume a car horn blows in the distance. Sound waves spread through the air from the horn. Some of the sound waves reach your ear. The steps below show what happens next. They explain how your ears sense the sound.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Some spindle microtubules attach to the kinetochores of chromosomes and move the chromosomes to what plate?","choices":["interstitium plate","metaphase plate","boundary plate","prophase plate"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do plants use to make food for themselves and most other organisms?","choices":["electricity","gravity","heat","light"],"answer":"D","rationale":"Visible light includes all the wavelengths of light that the human eye can detect. Humans and virtually all other organisms depend on visible light to survive. Humans and many other animals use it to see. Plants use it to make food for themselves and most other organisms.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Chlorophylls and carotenoids are the two major classes of pigments associated with what process and found in plants and algae?","choices":["photosynthesis","mitosis","glycolysis","osmosis"],"answer":"A","rationale":"Understanding Pigments Different kinds of pigments exist, and each has evolved to absorb only certain wavelengths (colors) of visible light. Pigments reflect or transmit the wavelengths they cannot absorb, making them appear in the corresponding color. Chlorophylls and carotenoids are the two major classes of photosynthetic pigments found in plants and algae; each class has multiple types of pigment molecules. There are five major chlorophylls: a, b, c and d and a related molecule found in prokaryotes called bacteriochlorophyll. Chlorophyll a and chlorophyll b are found in higher plant chloroplasts and will be the focus of the following discussion. With dozens of different forms, carotenoids are a much larger group of pigments. The carotenoids found in fruit\u2014such as the red of tomato (lycopene), the yellow of corn seeds (zeaxanthin), or the orange of an orange peel (\u03b2-carotene)\u2014are used as advertisements to attract seed dispersers. In photosynthesis, carotenoids function as photosynthetic pigments that are very efficient molecules for the disposal of excess energy. When a leaf is exposed to full sun, the light-dependent reactions are required to process an enormous amount of energy; if that energy is not handled properly, it can do significant damage. Therefore, many carotenoids reside in the thylakoid membrane, absorb excess energy, and safely dissipate that energy as heat. Each type of pigment can be identified by the specific pattern of wavelengths it absorbs from visible light, which is the absorption spectrum. The graph in Figure 8.13 shows the absorption spectra for chlorophyll a, chlorophyll b, and a type of carotenoid pigment called \u03b2-carotene (which absorbs blue and green light). Notice how each pigment has a distinct set of peaks and troughs, revealing a highly specific pattern of absorption. Chlorophyll a absorbs wavelengths from either end of the visible spectrum (blue and red), but not green. Because green is reflected or transmitted, chlorophyll appears green. Carotenoids absorb in the short-wavelength blue region, and reflect the longer yellow, red, and orange wavelengths.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is created when you combine simple machines?","choices":["factories","compound machines","motors","digital devices"],"answer":"B","rationale":"Compound machines such as a wheelbarrow or corkscrew consist of just two simple machines. Big compound machines such as cars consist of hundreds or thousands of simple machines.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the general term for a parasite that causes disease ?","choices":["noxious parasite","predator parasite","pathogenic parasite","avian parasite"],"answer":"C","rationale":"Bacteria: Friend or Foe? at http:\/\/biology. about. com\/cs\/bacteriology\/a\/aa032504a. htm .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What device measures atmospheric pressure and can be used as an altimeter?","choices":["barometer","thermometer","indicator","speedometer"],"answer":"A","rationale":"A barometer is a device that measures atmospheric pressure. A mercury barometer is shown in Figure 11.18. This device measures atmospheric pressure, rather than gauge pressure, because there is a nearly pure vacuum above the mercury in the tube. The height of the mercury is such that h\u03c1g = P atm . When atmospheric pressure varies, the mercury rises or falls, giving important clues to weather forecasters. The barometer can also be used as an altimeter, since average atmospheric pressure varies with altitude. Mercury barometers and manometers are so common that units of mm Hg are often quoted for atmospheric pressure and blood pressures. Table 11.2 gives conversion factors for some of the more commonly used units of pressure.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are solid-solid solutions like brass and bronze called?","choices":["mixtures","alloys","amalgams","oxides"],"answer":"B","rationale":"Solid-solid solutions such as brass, bronze, and sterling silver are called alloys. Bronze (composed mainly of copper with added tin) was widely used in making weapons in times past dating back to at least 2400 B. C. This metal alloy was hard and tough, but was eventually replaced by iron.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the main element in organic compounds?","choices":["hydrogen","helium","carbon","oxygen"],"answer":"C","rationale":"A compound found mainly in living things is known as an organic compound . Organic compounds make up the cells and other structures of organisms and carry out life processes. Carbon is the main element in organic compounds, so carbon is essential to life on Earth. Without carbon, life as we know it could not exist.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In living systems, diffusion of substances into and out of cells is mediated by the what?","choices":["plasma membrane","Plant membrane","cells membrane","battery membrane"],"answer":"A","rationale":"3.5 Passive Transport The passive forms of transport, diffusion and osmosis, move material of small molecular weight. Substances diffuse from areas of high concentration to areas of low concentration, and this process continues until the substance is evenly distributed in a system. In solutions of more than one substance, each type of molecule diffuses according to its own concentration gradient. Many factors can affect the rate of diffusion, including concentration gradient, the sizes of the particles that are diffusing, and the temperature of the system. In living systems, diffusion of substances into and out of cells is mediated by the plasma membrane. Some materials diffuse readily through the membrane, but others are hindered, and their passage is only made possible by protein channels and carriers. The chemistry of living things occurs in aqueous solutions, and balancing the concentrations of those solutions is an ongoing problem. In living systems, diffusion of some substances would be slow or difficult without membrane proteins.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Desertification can result from slash-and-burn agriculture, which causes loss of what?","choices":["subsoil","sediment","topsoil","fertilizer"],"answer":"C","rationale":"Slash-and-burn agriculture can lead to desertification, meaning the fertile top soil is lost.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are certain numbers of nucleons, known as magic numbers stable against?","choices":["half-lifes","radiation","nuclear decay","water"],"answer":"C","rationale":"certain numbers of nucleons, known as magic numbers, are stable against nuclear decay. These numbers of protons or neutrons (2, 8, 20, 28, 50, 82, and 126) make complete shells in the nucleus. These are similar in concept to the stable electron shells observed for the noble gases. Nuclei that have magic numbers of both protons and neutrons, such as 42 He, 168 O, 40 and 208 are called \u201cdouble magic\u201d and are particularly stable. These trends in 20 Ca, 82 Pb, nuclear stability may be rationalized by considering a quantum mechanical model of nuclear energy states analogous to that used to describe electronic states earlier in this textbook. The details of this model are beyond the scope of this chapter. Stable Nuclear Isotopes Number of Stable Isotopes.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Electron capture occurs when an inner shell electron combines with a proton and is converted into what?","choices":["photon","nuclei","protein","neutron"],"answer":"D","rationale":"Figure 12.4 An overhead view of a car passing a truck on a highway. Air passing between the vehicles flows in a narrower channel and must increase its speed ( v 2 is greater than v 1 ), causing the pressure between them to drop ( P i is less than P o ). Greater pressure on the outside pushes the car and truck together.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What system consists of neurons that carry signals to skeletal muscles?","choices":["circulatory system","endocrine system","nervous system","motor system"],"answer":"D","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cross-pollination\u2014or out-crossing\u2014leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from what?","choices":["the same plant","the same species","dead plants","different plants"],"answer":"D","rationale":"Explore this interactive website (http:\/\/openstaxcollege. org\/l\/pollination) to review self-pollination and crosspollination. Living species are designed to ensure survival of their progeny; those that fail become extinct. Genetic diversity is therefore required so that in changing environmental or stress conditions, some of the progeny can survive. Self-pollination leads to the production of plants with less genetic diversity, since genetic material from the same plant is used to form gametes, and eventually, the zygote. In contrast, cross-pollination\u2014or out-crossing\u2014leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from different plants. Because cross-pollination allows for more genetic diversity, plants have developed many ways to avoid self-pollination. In some species, the pollen and the ovary mature at different times. These flowers make self-pollination nearly impossible. By the time pollen matures and has been shed, the stigma of this flower is mature and can only be pollinated by pollen from another flower. Some flowers have developed physical features that prevent self-pollination. The primrose is one such flower. Primroses have evolved two flower types with differences in anther and stigma length: the pin-eyed flower has anthers positioned at the pollen tube\u2019s halfway point, and the thrum-eyed flower\u2019s stigma is likewise located at the halfway point. Insects easily cross-pollinate while seeking the nectar at the bottom of the pollen tube. This phenomenon is also known as heterostyly. Many plants, such as cucumber, have male and female flowers located on different parts of the plant, thus making self-pollination difficult. In yet other species, the male and female flowers are borne on different plants (dioecious). All of these are barriers to self-pollination; therefore, the plants depend on pollinators to transfer pollen. The majority of pollinators are biotic agents such as insects (like bees, flies, and butterflies), bats, birds, and other animals. Other plant species are pollinated by abiotic agents, such as wind and water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cancers are caused by a series of what?","choices":["mutations","adaptations","parasites","microbes"],"answer":"A","rationale":"Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell. In this example, the first mutation inactivates a tumor suppressor gene, the second mutation inactivates a DNA repair gene, the third mutation creates an oncogene, and a fourth mutation inactivates several more tumor suppressor genes, resulting in cancer. It should be noted that it does not necessarily require four or more mutations to lead to cancer.","split":"validation","source_dataset":"sciq","subject":null},{"question":"In comparison to light, the speed of sound is faster or slower?","choices":["the same","slower","sound does does not travel","faster"],"answer":"B","rationale":"Figure 17.8 When a firework explodes, the light energy is perceived before the sound energy. Sound travels more slowly than light does. (credit: Dominic Alves, Flickr).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What type of fossils are of organisms that lived over a wide area for a fairly short period of time and are used to determine the age of the rock it is in?","choices":["rate fossils","index fossils","inventory fossils","reference fossils"],"answer":"B","rationale":"Fossils are used to determine the ages of rock layers. Index fossils are the most useful for this. Index fossils are of organisms that lived over a wide area. They lived for a fairly short period of time. An index fossil allows a scientist to determine the age of the rock it is in.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What term is defined as the preserved remains or traces of organisms that lived during earlier ages?","choices":["taxidermy","deposits","archaeology","fossils"],"answer":"D","rationale":"Fossils are the preserved remains or traces of organisms that lived during earlier ages. Remains that become fossils are generally the hard parts of organisms\u2014mainly bones, teeth, or shells. Traces include any evidence of life, such as footprints like the dinosaur footprint in Figure below . Fossils are like a window into the past. They provide direct evidence of what life was like long ago. A scientist who studies fossils to learn about the evolution of living things is called a paleontologist .","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which glands produce milk after the birth of offspring?","choices":["Pituitary gland","adrenal glands","mammary","Thyroid gland"],"answer":"C","rationale":"All female mammals have mammary glands. Mammary glands are glands that produce milk after the birth of offspring. Producing milk for offspring is called lactation. The colt in Figure below is getting milk from its mother.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Reduction often involves the gain of hydrogen, the loss of oxygen, or the gain of what?","choices":["protons","neutrons","mass","electrons"],"answer":"D","rationale":"Reduction often involves the gain of hydrogen, the loss of oxygen, or the gain of electrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is a short band of tough connective tissue that connects bones together to form a joint?","choices":["a tendon","muscle tissue","a ligament","cartilage"],"answer":"C","rationale":"Recall that a ligament is a short band of tough connective tissue that connects bones together to form a joint. Ligaments can get injured when a joint gets twisted or bends too far. The protein fibers that make up a ligament can get strained or torn, causing swelling and pain. Injuries to ligaments are called sprains . Ankle sprains are a common type of sprain.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When you burn wood into ash or burn a marshmallow to become brown and crispy, it is impossible to undo.  this change is known as what?","choices":["chemical change","carbon change","physical change","compounding change"],"answer":"A","rationale":"Yummy! S\u2019mores are on the way! Did you ever toast marshmallows over a campfire? The sweet treats singe on the outside and melt on the inside. Both the fire and the toasted marshmallows are evidence of chemical changes. In the process of burning, the wood changes to ashes and gases, and the outside of the marshmallow turns brown and crispy. Neither the wood nor the marshmallows can change back to their original form. That\u2019s because burning is a chemical change and chemical changes are often impossible to undo. In this unit, you\u2019ll learn about many types of chemical changes, including how they occur and why you can\u2019t live without them.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which biomes are determined mainly by sunlight and concentrations of dissolved oxygen and nutrients in the water?","choices":["aquatic","viral","symbiotic","bacterial"],"answer":"A","rationale":"Aquatic biomes are determined mainly by sunlight and concentrations of dissolved oxygen and nutrients in the water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the moon's shadow's inner part called?","choices":["penumbra","mullah","aurora","umbra"],"answer":"D","rationale":"The Moon\u2019s shadow has two distinct parts. The umbra is the inner, cone-shaped part of the shadow. It is the part in which all of the light has been blocked. The penumbra is the outer part of Moon\u2019s shadow. It is where the light is only partially blocked.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The earliest known mammal fossils are from which period?","choices":["Cretaceous Period","Mesosoic period","Tertiary","early jurassic"],"answer":"D","rationale":"A key characteristic of synapsids is endothermy, rather than the ectothermy seen in most other vertebrates. The increased metabolic rate required to internally modify body temperature went hand in hand with changes to certain skeletal structures. The later synapsids, which had more evolved characteristics unique to mammals, possess cheeks for holding food and heterodont teeth, which are specialized for chewing, mechanically breaking down food to speed digestion and releasing the energy needed to produce heat. Chewing also requires the ability to chew and breathe at the same time, which is facilitated by the presence of a secondary palate. A secondary palate separates the area of the mouth where chewing occurs from the area above where respiration occurs, allowing breathing to proceed uninterrupted during chewing. A secondary palate is not found in pelycosaurs but is present in cynodonts and mammals. The jawbone also shows changes from early synapsids to later ones. The zygomatic arch, or cheekbone, is present in mammals and advanced therapsids such as cynodonts, but is not present in pelycosaurs. The presence of the zygomatic arch suggests the presence of the masseter muscle, which closes the jaw and functions in chewing. In the appendicular skeleton, the shoulder girdle of therian mammals is modified from that of other vertebrates in that it does not possess a procoracoid bone or an interclavicle, and the scapula is the dominant bone. Mammals evolved from therapsids in the late Triassic period, as the earliest known mammal fossils are from the early Jurassic period, some 205 million years ago. Early mammals were small, about the size of a small rodent. Mammals first began to diversify in the Mesozoic Era, from the Jurassic to the Cretaceous periods, although most of these mammals were extinct by the end of the Mesozoic. During the Cretaceous period, another radiation of mammals began and continued through the Cenozoic Era, about 65 million years ago.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Each parapodium has numerous chaetae, bristles made of what?","choices":["casein","lectin","chitin","ricin"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What phylum includes sponges, which are aquatic invertebrates?","choices":["hymenoptera","chordata","mollusca","porifera"],"answer":"D","rationale":"Sponges are aquatic invertebrates in Phylum Porifera. Sponges have specialized cells and an endoskeleton, but they lack tissues and body symmetry. Many live on coral reefs and have symbiotic relationships with other reef species.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which are the three most important temperature scales?","choices":["Kelvin, celcius, richter","thermoelectric , celsius , kelvin","temperatures , celsius , kelvin","fahrenheit, celsius, kelvin"],"answer":"D","rationale":"Temperature Scales Thermometers are used to measure temperature according to well-defined scales of measurement, which use pre-defined reference points to help compare quantities. The three most common temperature scales are the Fahrenheit, Celsius, and Kelvin scales. A temperature scale can be created by identifying two easily reproducible temperatures. The freezing and boiling temperatures of water at standard atmospheric pressure are commonly used. The Celsius scale (which replaced the slightly different centigrade scale) has the freezing point of water at point at.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What part of the body does caffeine stimulate?","choices":["autonomic nervous system","large nervous system","central nervous system","sympathetic nervous system"],"answer":"C","rationale":"Some psychoactive drugs, such as caffeine, stimulate the central nervous system. They may make the user feel more alert. Some psychoactive drugs, such as alcohol, depress the central nervous system. They may make the user feel more relaxed. Still other psychoactive drugs, such as marijuana, are hallucinogenic drugs. They may make the user have altered sensations, perceptions, or thoughts.","split":"validation","source_dataset":"sciq","subject":null},{"question":"An alpha particle, which is emitted during alpha decay, consists of two protons and what else?","choices":["two nuclei","two electrons","two positrons","two neutrons"],"answer":"D","rationale":"A: Along with another electron, it can combine with an alpha particle to form a helium atom. An alpha particle, which is emitted during alpha decay, consists of two protons and two neutrons.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Melanin in skin is produced in response to exposure to what type of light?","choices":["x rays","infrared light","uv light","visible light"],"answer":"C","rationale":"Intermediate Pituitary: Melanocyte-Stimulating Hormone The cells in the zone between the pituitary lobes secrete a hormone known as melanocyte-stimulating hormone (MSH) that is formed by cleavage of the pro-opiomelanocortin (POMC) precursor protein. Local production of MSH in the skin is responsible for melanin production in response to UV light exposure. The role of MSH made by the pituitary is more complicated. For instance, people with lighter skin generally have the same amount of MSH as people with darker skin. Nevertheless, this hormone is capable of darkening of the skin by inducing melanin production in the skin\u2019s melanocytes. Women also show increased MSH production during pregnancy; in combination with estrogens, it can lead to darker skin pigmentation, especially the skin of the areolas and labia minora. Figure 17.11 is a summary of the pituitary hormones and their principal effects.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Protein molecules are made up of chains of small molecules made up of what kinds of acids?","choices":["hydrochloric acids","mutation acids","amino acids","rna acids"],"answer":"C","rationale":"Proteins are biochemical compounds that contain oxygen, nitrogen, and sulfur in addition to carbon and hydrogen. Protein molecules consist of one or more chains of small molecules called amino acids.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which element has the highest electronegativity value?","choices":["chlorine","Barium","fluorine","magnesium"],"answer":"C","rationale":"The highest electronegativity value is for fluorine.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When small particles, such as clay and silt, are in mixed in water but do not disolve in the water, what state are they in?","choices":["mud","incomplete","sedimentation","suspension"],"answer":"D","rationale":"Small particles, such as clay and silt, are carried in suspension . They are mixed throughout the water. These particles are not dissolved in the water.","split":"validation","source_dataset":"sciq","subject":null},{"question":"When a person stands on the floor, his feet exert what on the surface?","choices":["pressure","power","acceleration","resistance"],"answer":"A","rationale":"When a person stands on the floor, his feet exert pressure on the surface. That pressure is related to both the mass of the person and the surface area of his feet. If the person were holding a heavy object, the pressure would increase because of a greater force. Alternatively, if the person stands on his toes, the pressure also increases because of a decrease in the surface area.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Molds that grow on bread are from what kingdom?","choices":["fungi","pollen","animal","yeast"],"answer":"A","rationale":"Do you see the organisms growing on the bread in Figure below ? They belong to the Kingdom Fungi. Molds growing on foods are some of the most common fungi in our everyday lives. These organisms may seem useless, gross, and costly. But fungi play very important roles in almost every terrestrial ecosystem on Earth.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is defined as the change in the size of the population over time?","choices":["population growth","population density","overpopulation","extinction"],"answer":"A","rationale":"Population growth is the change in the size of the population over time. An important factor in population growth is age-sex structure . This is the number of individuals of each sex and age in the population. The age-sex structure influences population growth. This is because younger people are more likely to reproduce, while older people have higher rates of dying.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The frequency of sound waves is measured in what, or the number of waves that pass a fixed point in a second?","choices":["Ohms","watts","avis","hertz"],"answer":"D","rationale":"The frequency of sound waves is measured in hertz (Hz), or the number of waves that pass a fixed point in a second. Human beings can normally hear sounds with a frequency between about 20 Hz and 20,000 Hz. Sounds with frequencies below 20 hertz are called infrasound . Sounds with frequencies above 20,000 hertz are called ultrasound . Some other animals can hear sounds in the ultrasound range. For example, dogs can hear sounds with frequencies as high as 50,000 Hz. You may have seen special whistles that dogs but not people can hear. The whistles produce a sound with a frequency too high for the human ear to detect. Other animals can hear even higher-frequency sounds. Bats, for example, can hear sounds with frequencies higher than 100,000 Hz.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are examples of parasitic athropods?","choices":["spiders and fleas","bees and wasps","ticks and many mites","crabs and clams"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"In a position-time graph, what does the slope of the line represent?","choices":["time","velocity","position","direction"],"answer":"B","rationale":"In a position-time graph, the velocity of the moving object is represented by the slope, or steepness, of the graph line. If the graph line is horizontal, like the line after time = 5 seconds in Graph 2 in the Figure below , then the slope is zero and so is the velocity. The position of the object is not changing. The steeper the line is, the greater the slope of the line is and the faster the object\u2019s motion is changing.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Salmon must do what when they migrate from freshwater to the ocean?","choices":["synthesize","acclimatize","regenerate","adapt"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What occurs when two free radicals come in contact with each other?","choices":["radiation","assimilation","termination","cancellation"],"answer":"C","rationale":"Termination occurs whenever two free radicals come in contact with one another (not shown). The two free electrons form a covalent bond and the free radical on each molecule no longer exists.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Despite the season, what aspect of constellations never change?","choices":["size","location","patterns","colors"],"answer":"C","rationale":"The constellations stay the same night after night. The patterns of the stars never change. However, each night the constellations move across the sky. They move because Earth is spinning on its axis. The constellations also move with the seasons. This is because Earth revolves around the Sun. The constellations in the winter are different from those in the summer. For example, Orion is high up in the winter sky. In the summer, it's only up in the early morning.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do you call electrons that form bonds with other elements in compounds and generally determine the properties of elements?","choices":["isotopes","valence electrons","shell electrons","ionic electrons"],"answer":"B","rationale":"Other properties of the transition metals are unique. They are the only elements that may use electrons in the next to highest\u2014as well as the highest\u2014energy level as valence electrons. Valence electrons are the electrons that form bonds with other elements in compounds and that generally determine the properties of elements. Transition metals are unusual in having very similar properties even with different numbers of valence electrons. The transition metals also include the only elements that produce a magnetic field. Three of them have this property: iron (Fe), cobalt (Co), and nickel (Ni).","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the members of the clade vertebrata known as?","choices":["vertebrates","grasses","lipids","invertebrates"],"answer":"A","rationale":"Vertebrates are members of the clade Vertebrata. Vertebrates display the four characteristic features of the chordates; however, members of this group also share derived characteristics that distinguish them from invertebrate chordates. Vertebrata is named for the vertebral column, composed of vertebrae, a series of separate bones joined together as a backbone (Figure 29.7). In adult vertebrates, the vertebral column replaces the notochord, which is only seen in the embryonic stage.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What two ways do fruits mainly disperse seeds?","choices":["roots and decay","animals and wind","birds and wind","bees and water"],"answer":"B","rationale":"Fruits are adapted to disperse seeds with the help of animals or the wind.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What helps maglev trains go very fast?","choices":["gravity","rollers","wheels","magnets"],"answer":"D","rationale":"The futuristic-looking train in Figure below is called a maglev train. The word \"maglev\" stands for \"magnetic levitation. \" Magnets push the train upward so it hovers, or levitates, above the track without actually touching it. This eliminates most of the friction acting against the train when it moves. Other magnets pull the train forward along the track. Because of these magnets, the train can go very fast. It can fly over the countryside at speeds up to 480 kilometers (300 miles) per hour! What are magnets and how do they exert such force? In this lesson, you\u2019ll find out.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the study of energy changes that occur during chemical reactions and during changes of state?","choices":["thermobiology","thermochemistry","nuclear chemistry","nuclear biology"],"answer":"B","rationale":"Thermochemistry is the study of energy changes that occur during chemical reactions and during changes of state. When chemical reactions occur, some chemical bonds are broken, while new chemical bonds form. As a result of the rearrangement of atoms, the total chemical potential energy of the system either increases or decreases.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Hormones that share what usually perform the same function?","choices":["glandular process","chemical class","temperature","radiation class"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"A glacier is an example of h20 in which state of matter?","choices":["solid","stable","gas","liquid"],"answer":"A","rationale":"The state of matter is a physical property of that matter. H 2 O can exist in three different states of matter. This glacier is obviously a solid state of H 2 O, floating in the liquid state. Why does the ice float on water? Which has a greater density, solid H 2 O or liquid H 2 O?.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Silver chloride can be used as an antidote for which kind of poisoning?","choices":["carbon monoxide","the bends","mercury","arsenic"],"answer":"C","rationale":"Silver chloride is an important compound that is commonly used in the production of photographic film. It also has many other uses, such as an antidote for mercury poisoning, a component of pottery glazes, and a reference standard for electrochemistry setups. It can be produced according to the reaction shown above. Now we will practice use of mole ratios and stoichiometry to determine the amounts of products and reactants necessary in our reaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What do we call the microflora that aid in the digestion process?","choices":["intestinal flora","tissue flora","stomach flora","digestive flora"],"answer":"A","rationale":"Elimination The final step in digestion is the elimination of undigested food content and waste products. The undigested food material enters the colon, where most of the water is reabsorbed. Recall that the colon is also home to the microflora called \u201cintestinal flora\u201d that aid in the digestion process. The semi-solid waste is moved through the colon by peristaltic movements of the muscle and is stored in the rectum. As the rectum expands in response to storage of fecal matter, it triggers the neural signals required to set up the urge to eliminate. The solid waste is eliminated through the anus using peristaltic movements of the rectum.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nitrogen also is released to the environment by decaying organisms or decaying wastes. these wastes release nitrogen in the form of what?","choices":["sulfide","ammonium","methane","hydroxide"],"answer":"B","rationale":"Nitrogen also is released to the environment by decaying organisms or decaying wastes. These wastes release nitrogen in the form of ammonium.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What requirement of the second circuit does the current that flows in the primary circuit depend on?","choices":["composition of current","velocity of current","amount of current","accumulation of current"],"answer":"C","rationale":"The current that flows in the primary depends on how much current is required by the secondary circuit.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Mammalian sex determination is determined genetically by the presence of chromosomes identified by what letters?","choices":["a and b","y and z","rna and dna","x and y"],"answer":"D","rationale":"Sex Determination Mammalian sex determination is determined genetically by the presence of X and Y chromosomes. Individuals homozygous for X (XX) are female and heterozygous individuals (XY) are male. The presence of a Y chromosome causes the development of male characteristics and its absence results in female characteristics. The XY system is also found in some insects and plants. Avian sex determination is dependent on the presence of Z and W chromosomes. Homozygous for Z (ZZ) results in a male and heterozygous (ZW) results in a female. The W appears to be essential in determining the sex of the individual, similar to the Y chromosome in mammals. Some fish, crustaceans, insects (such as butterflies and moths), and reptiles use this system. The sex of some species is not determined by genetics but by some aspect of the environment. Sex determination in some crocodiles and turtles, for example, is often dependent on the temperature during critical periods of egg development. This is referred to as environmental sex determination, or more specifically as temperature-dependent sex determination. In many turtles, cooler temperatures during egg incubation produce males and warm temperatures produce females. In some crocodiles, moderate temperatures produce males and both warm and cool temperatures produce females. In some species, sex is both genetic- and temperature-dependent. Individuals of some species change their sex during their lives, alternating between male and female. If the individual is female first, it is termed protogyny or \u201cfirst female,\u201d if it is male first, its termed protandry or \u201cfirst male. \u201d Oysters, for example, are born male, grow, and become female and lay eggs; some oyster species change sex multiple times.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What kind of symmetry do most adult echinoderms possess?","choices":["radial symmetry","spherical","bilateral","asymmetry"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What happens if cancer cells enter the blood stream?","choices":["they die","they mutate","they enter the brain","carried through body"],"answer":"D","rationale":"As a tumor increases in size, it may harm normal tissues around it. Sometimes cancer cells break away from a tumor. If they enter the bloodstream, they are carried throughout the body. Then the cells may start growing in other tissues. This is usually how cancer spreads from one part of the body to another. Once this happens, cancer is very hard to stop.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Fires, mainly caused by what, are a natural disturbance in temperate grasslands?","choices":["campfires","humans","cigarettes","lightning"],"answer":"D","rationale":"Fires, mainly caused by lightning, are a natural disturbance in temperate grasslands. When fire is suppressed in temperate grasslands, the vegetation eventually converts to scrub and dense forests. Often, the restoration or management of temperate grasslands requires the use of controlled burns to suppress the growth of trees and maintain the grasses.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the net force acting on an object when two equal forces are applied from opposite directions?","choices":["zero","homeostasis","negative","sum"],"answer":"A","rationale":"When two forces act on an object in opposite directions, like the book on the table, the net force is equal to the difference between the two forces. In other words, one force is subtracted from the other to calculate the net force. If the opposing forces are equal in strength, the net force is zero. That\u2019s what happens with the book on the table. The upward force minus the downward force equals zero (20 N up - 20 N down = 0 N). Because the forces on the book are balanced, the book remains on the table and doesn\u2019t move.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Insects use what structures, located on the head, to smell and taste chemicals, and in some cases to hear sounds?","choices":["caripace","antennae","appendages","legs"],"answer":"B","rationale":"The head has a pair of antennae. Insects use their antennae to smell and taste chemicals. Some insects can also use their antennae to hear sounds.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The carbon cycle includes photosynthesis, in which plants change what to organic compounds?","choices":["carbon monoxide","chemical dioxide","acid dioxide","carbon dioxide"],"answer":"D","rationale":"The carbon cycle includes photosynthesis, in which plants change carbon dioxide to organic compounds. It also includes cellular respiration, in which living things \u201cburn\u201d organic compounds and release carbon dioxide. Rocks, fossil fuels, and the ocean are also part of the carbon cycle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Nucleic acids are found in all living cells and also what?","choices":["parasites","bacteria","viruses","fungi"],"answer":"C","rationale":"Nucleic acids are organic compounds that contain carbon, hydrogen, oxygen, nitrogen, and phosphorus. They are made of smaller units called nucleotides . Nucleic acids are named for the nucleus of the cell, where some of them are found. Nucleic acids are found not only in all living cells but also in viruses. Types of nucleic acids include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) .","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the gelatinous layer that is sandwiched between the epidermis and gastrodermis?","choices":["myelin sheath","plasmid","the mesoglea","aqueous humor"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Mollusks can be divided into how many classes?","choices":["seven","three","four","nine"],"answer":"A","rationale":"stages: trochophore and veliger. Sexual dimorphism is the predominant sexual strategy in this phylum. Mollusks can be divided into seven classes, each with distinct morphological characteristics.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Stars are lit by what reaction?","choices":["Coriolis effect","ionization","nuclear fission","nuclear fusion"],"answer":"D","rationale":"The points of light in the night sky are stars that are balls of gas. They are lit by nuclear fusion.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for a partial degradation of glucose without the use of oxygen?","choices":["fermentation","oxidation","segregation","condensation"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the term for the measurement of the amount of variation of species in a given area?","choices":["biodiversity","reproduction","ecosystem","divergence"],"answer":"A","rationale":"Biodiversity is a measurement of the amount of variation of the species in a given area.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The radioactive gas radon and uv radiation are culprits in different types of what disease?","choices":["metabolic disease","reproductive","diabetes","cancer"],"answer":"D","rationale":"UV radiation is the leading cause of skin cancer. The radioactive gas known as radon causes lung cancer.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is used to show energy flow through the trophic levels?","choices":["inverted food chain","biome graph","food pyramid","pyramid ecosystem"],"answer":"D","rationale":"Pyramid ecosystem modeling can also be used to show energy flow through the trophic levels. Notice that these numbers are the same as those used in the energy flow compartment diagram in Figure 46.8. Pyramids of energy are always upright, and an ecosystem without sufficient primary productivity cannot be supported. All types of ecological pyramids are useful for characterizing ecosystem structure. However, in the study of energy flow through the ecosystem, pyramids of energy are the most consistent and representative models of ecosystem structure (Figure 46.10).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Compared to a straight wire, a coiled wire has a stronger what?","choices":["proximate field","gravitational field","horizontal field","magnetic field"],"answer":"D","rationale":"Any wire with current flowing through it has a magnetic field. However, the magnetic field around a coiled wire is stronger than the magnetic field around a straight wire. That\u2019s because each turn of the wire in the coil has its own magnetic field. Adding more turns to the coil of wire increases the strength of the field. Increasing the amount of current flowing through the coil also increases the strength of the magnetic field.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The extrusive type of what rock cools rapidly from lava at the surface?","choices":["igneous","crystalline","erythematous","precipitous"],"answer":"A","rationale":"Extrusive igneous rocks cool from lava rapidly at the surface. They have small crystals.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The burning of fossil fuels releases three major things - thermal energy, water vapor, and what pollutant?","choices":["aluminum","hydrogen","carbon dioxide","carbon monoxide"],"answer":"C","rationale":"When fossil fuels burn, they release thermal energy, water vapor, and carbon dioxide. The thermal energy can be used to generate electricity or do other work. The carbon dioxide is released into the atmosphere and is a major cause of global climate change. The burning of fossil fuels also releases many pollutants into the air. Pollutants such as sulfur dioxide form acid rain, which kills living things and damages metals, stonework, and other materials. Pollutants such as nitrogen oxides cause smog, which is harmful to human health. Tiny particles, or particulates, released when fossil fuels burn also harm human health.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Ground collapse, associated with chambers of what substance, leads to formation of a caldera?","choices":["stone","magma","lava","molten"],"answer":"B","rationale":"The cause of supervolcano eruptions is being debated. Enormous magma chambers are filled with super hot magma. This enormous eruption leaves a huge hole. The ground collapses and creates a caldera.","split":"validation","source_dataset":"sciq","subject":null},{"question":"A habitat\u2019s features are determined mainly by abiotic factors such as?","choices":["temperature and rainfall","oxygen and rainfall","length","mixing and rainfall"],"answer":"A","rationale":"Another aspect of a species\u2019 niche is its habitat. The habitat is the physical environment in which a species lives and to which it is adapted. A habitat\u2019s features are determined mainly by abiotic factors such as temperature and rainfall. These factors also influence the traits of the organisms that live there.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Sulfuric acid conducts the charge in what kind of battery?","choices":["lead-acid cell","lithium ion","nickel cadmium","nickel-metal hydride"],"answer":"A","rationale":"Figure 21.10 Artist\u2019s conception of a lead-acid cell. Chemical reactions in a lead-acid cell separate charge, sending negative charge to the anode, which is connected to the lead plates. The lead oxide plates are connected to the positive or cathode terminal of the cell. Sulfuric acid conducts the charge as well as participating in the chemical reaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The pubis forms the anterior portion of what bone?","choices":["femur","clavicle","labia","hip bone"],"answer":"D","rationale":"Pubis The pubis forms the anterior portion of the hip bone (see Figure 8.13). The enlarged medial portion of the pubis is the pubic body. Located superiorly on the pubic body is a small bump called the pubic tubercle. The superior pubic ramus is the segment of bone that passes laterally from the pubic body to join the ilium. The narrow ridge running along the superior margin of the superior pubic ramus is the pectineal line of the pubis. The pubic body is joined to the pubic body of the opposite hip bone by the pubic symphysis. Extending downward and laterally from the body is the inferior pubic ramus. The pubic arch is the bony structure formed by the pubic symphysis, and the bodies and inferior pubic rami of the adjacent pubic bones. The inferior pubic ramus extends downward to join the ischial ramus. Together, these form the single ischiopubic ramus, which extends from the pubic body to the ischial tuberosity. The inverted V-shape formed as the ischiopubic rami from both sides come together at the pubic symphysis is called the subpubic angle.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the general term for water that falls from clouds to earth\u2019s surface, in forms that include snow and rain?","choices":["condensation","distillation","precipitation","groundwater"],"answer":"C","rationale":"Precipitation is water that falls from clouds to Earth\u2019s surface. Water droplets in clouds fall to Earth when they become too large to stay aloft. The water falls as rain if the air is warm. If the air is cold, the water may freeze and fall as snow, sleet, or hail. Most precipitation falls into the oceans. Some falls on land.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are an important predators of mosquitoes, that can be used to control this pest?","choices":["deers","primates","dogs","dragonflies"],"answer":"D","rationale":"Ladybugs also consume mites, scale insects and small caterpillars. The larvae of many hoverfly species also feed upon aphids, with one larva consuming up to fifty aphids a day, which is about 1,000 in its lifetime. They also eat fruit tree spider mites and small caterpillars. Dragonflies are important predators of mosquitoes, and can be used to control this pest. Parasitic insects include insects such as wasps and flies that lay their eggs on or in the body of an insect host, which is then used as a food for developing larvae. The host is ultimately killed. Caterpillars also tend to be one likely target of parasitic wasps.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Receptors for which hormones reside in the cytoplasm or nucleus?","choices":["cores - soluble hormones","lipid-soluble hormones","organism - soluble hormones","non lipid-soluble hormones"],"answer":"B","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Heterotrophs get food by eating what?","choices":["other organisms","plants","similar organisms","sand"],"answer":"A","rationale":"Protozoa are heterotrophs. Heterotrophs get food by eating other organisms. Some protozoa prey on bacteria. Some are parasites of animals. Others graze on algae. Still others are decomposers that break down dead organic matter.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process called when liquid changes to gas, even though it has not become hot enough to boil?","choices":["transpiration","expiration","oxidation","evaporation"],"answer":"D","rationale":"Evaporation explains why clothes dry on a clothesline. Evaporation is the process in which a liquid changes to a gas without becoming hot enough to boil. It occurs when individual liquid particles at the exposed surface of the liquid absorb just enough energy to overcome the force of attraction with other liquid particles. If the surface particles are moving in the right direction, they will pull away from the liquid and move into the air. This is illustrated in the Figure below .","split":"validation","source_dataset":"sciq","subject":null},{"question":"How often do partial lunar eclipses occur?","choices":["twice a year","2 times a year","once a year","6 times a year"],"answer":"A","rationale":"Partial lunar eclipses occur at least twice a year, but total lunar eclipses are less common. The Moon glows with a dull red coloring during a total lunar eclipse.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What are the trillions of bacteria living within the large intestine called?","choices":["bacteria flora","intastinal flora","microflora","probiotic"],"answer":"A","rationale":"Bacterial Flora Most bacteria that enter the alimentary canal are killed by lysozyme, defensins, HCl, or protein-digesting enzymes. However, trillions of bacteria live within the large intestine and are referred to as the bacterial flora. Most of the more than 700 species of these bacteria are nonpathogenic commensal organisms that cause no harm as long as they stay in the gut lumen. In fact, many facilitate chemical digestion and absorption, and some synthesize certain vitamins, mainly biotin, pantothenic acid, and vitamin K. Some are linked to increased immune response. A refined system prevents these bacteria from crossing the mucosal barrier. First, peptidoglycan, a component of bacterial cell walls, activates the release of chemicals by the mucosa\u2019s epithelial cells, which draft immune cells, especially dendritic cells, into the mucosa. Dendritic cells open the tight junctions between epithelial cells and extend probes into the lumen to evaluate the microbial antigens. The dendritic cells with antigens then travel to neighboring lymphoid follicles in the mucosa where T cells inspect for antigens. This process triggers an IgA-mediated response, if warranted, in the lumen that blocks the commensal organisms from infiltrating the mucosa and setting off a far greater, widespread systematic reaction.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the process by which rocks and other sediments are picked up by a glacier?","choices":["freezing","plucking","picking","pulling"],"answer":"B","rationale":"Plucking is the process by which rocks and other sediments are picked up by a glacier. They freeze to the bottom of the glacier and are carried away by the flowing ice.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Genetic variation produced in sexual life cycles contributes to what process?","choices":["deconstruction","maturity","generation","evolution"],"answer":"D","rationale":"13.4 Genetic variation produced in sexual life cycles contributes to evolution.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Animal claws, spines, and shells are examples of what strategy for survival?","choices":["spontaneous mutation","learned behavior","defense mechanism","display behavior"],"answer":"C","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"The jejunum is about 0.9 meters (3 feet) long (in life) and runs from the duodenum to the ileum. jejunum means \u201cempty\u201d in latin and supposedly was so named by the ancient greeks who noticed it was always what?","choices":["weeks at death","time.the at death","empty at death","black at death"],"answer":"C","rationale":"In relaxed muscle, the myosin-binding site on actin is blocked by ________. titin b. troponin c. myoglobin d. tropomyosin 17. The cell membrane of a muscle fiber is called a ________. myofibril b. sarcolemma c. sarcoplasm d. myofilament.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Cellular innate defenses in vertebrates also involve natural killer what?","choices":["cells","proteins","nerves","lipids"],"answer":"A","rationale":"","split":"validation","source_dataset":"sciq","subject":null},{"question":"Which construction material previously used in factories and in homes caused cancer?","choices":["Silica","Alkylphenols","asbestos","Paints contains lead"],"answer":"C","rationale":"The past use of asbestos in factories and in homes. Asbestos is a very dangerous material, and it was used in many buildings ( Figure below ). Asbestos can cause cancer and other lung diseases. The use of asbestos is not allowed today.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What is the number waves that pass a fixed point in a given amount of time called?","choices":["wave frequency","combination frequency","heating frequency","wave tendency"],"answer":"A","rationale":"Wave frequency is the number of waves that pass a fixed point in a given amount of time. Frequencies of electromagnetic waves range from thousands of waves per second to trillions of waves per second.","split":"validation","source_dataset":"sciq","subject":null},{"question":"The outer ear, or ear canal, carries sound to the recessed protected what?","choices":["ear lobe","eardrum","aorta","lungs"],"answer":"B","rationale":"The outer ear, or ear canal, carries sound to the recessed protected eardrum. The air column in the ear canal resonates and is partially responsible for the sensitivity of the ear to sounds in the 2000 to 5000 Hz range. The middle ear converts sound into mechanical vibrations and applies these vibrations to the cochlea. The lever system of the middle ear takes the force exerted on.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What sport involves people quickly finding destinations using polar coordinates?","choices":["orienteering","patterning","mapping","sticking"],"answer":"A","rationale":"Polar coordinates are used in a sport called orienteering. People who do orienteering use a compass and a map with polar coordinates. Participants find their way along a course across wilderness terrain ( Figure below ). They move to various checkpoints along the course. The winner is the person who completes the course in the fastest time.","split":"validation","source_dataset":"sciq","subject":null},{"question":"Almost all earthquakes occur at which place?","choices":["land boundaries","plate boundaries","continental shelf","mountains"],"answer":"B","rationale":"Almost all earthquakes occur at plate boundaries. All types of plate boundaries have earthquakes. Convection within the Earth causes the plates to move. As the plates move, stresses build. When the stresses build too much, the rocks break. The break releases the energy that was stored in the rocks. The sudden release of energy creates an earthquake. During an earthquake the rocks usually move several centimeters or rarely as much as a few meters. Elastic rebound theory describes how earthquakes occur ( Figure below ).","split":"validation","source_dataset":"sciq","subject":null},{"question":"Melting glaciers, rising temperatures and droughts are all impacts of what?","choices":["air pollution","nature's natural cycle","global warming","sudden warming"],"answer":"C","rationale":"Melting glaciers, rising temperatures and droughts are all impacts of global warming. But how does global warming actually affect the oceans? The sea, it turns out, absorbs carbon dioxide emissions. The ocean acts like a giant sponge, absorbing carbon dioxide emissions from the air. And as we add more and more carbon dioxide to air by burning fossil fuels, the ocean is absorbing it. On one level, it's done us a big favor. Scientists say that we would be experiencing much more extreme climate change were it not for the ocean's ability to remove the heat-trapping gas. However, these emissions are causing the oceans to become more acidic. Changing pH levels threaten entire marine food webs, from coral reefs to salmon. See http:\/\/www. kqed. org\/quest\/radio\/acidic-seas for additional information.","split":"validation","source_dataset":"sciq","subject":null},{"question":"What parts of a human possess the highest concentration of thermoreceptors?","choices":["face and hair","hands and feet","hand and ears","face and ears"],"answer":"D","rationale":"Thermoreceptors perceive sensations related to the temperature of objects. There are two basic categories of thermoreceptors: hot receptors and cold receptors. The highest concentration of thermoreceptors can be found in the face and ears.","split":"validation","source_dataset":"sciq","subject":null}]