questions stringlengths 37 1.22k | reasoning stringlengths 0 3.56k ⌀ | answers stringlengths 4 138 |
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Einstein developed a theory about how electromagnetic radiation can behave as both a wave and what else?
Here are the choices:
A. bacteria
B. energy
C. sound
D. particle | In 1905, the physicist Albert Einstein developed a new theory about electromagnetic radiation. The theory is often called the wave-particle theory . It explains how electromagnetic radiation can behave as both a wave and a particle. Einstein argued that when an electron returns to a lower energy level and gives off electromagnetic energy, the energy is released as a discrete “packet” of energy. We now call such a packet of energy a photon . According to Einstein, a photon resembles a particle but moves like a wave. You can see this in the Figure below . The theory posits that waves of photons traveling through space or matter make up electromagnetic radiation. | D: particle. |
What type of proteins are only temporarily associated with the membrane?
Here are the choices:
A. peripheral membrane proteins
B. sensitive rod proteins
C. visual membrane proteins
D. peripheral oxidation proteins | Peripheral membrane proteins are proteins that are only temporarily associated with the membrane. They can be easily removed, which allows them to be involved in cell signaling. Peripheral proteins can also be attached to integral membrane proteins, or they can stick into a small portion of the lipid bilayer by themselves. Peripheral membrane proteins are often associated with ion channels and transmembrane receptors. Most peripheral membrane proteins are hydrophilic. | A: peripheral membrane proteins. |
Which organisms break down either organic or inorganic molecules to supply energy for the cell?
Here are the choices:
A. asexual organisms
B. chemotrophic organisms
C. photoreactive organisms
D. spicule organisms | Chemotrophic organisms break down either organic or inorganic molecules to supply energy for the cell. Some chemotrophic organisms can also use their organic energy-supplying molecules as a carbon supply, which would make them chemoheterotrophs. | B: chemotrophic organisms. |
What are the things moving under the earth's mantle that move the crust?
Here are the choices:
A. crystals
B. plates
C. lava channels
D. ridges | What portion of Earth makes up the “plates” in plate tectonics? Again, the answer came about in part due to war. In this case, the Cold War. The scientists set up seismometer networks during the 1950s and early 1960s. The purpose was to see if other nations were testing atomic bombs. Since seismometers measure ground shaking, they also recorded earthquakes. | B: plates. |
Although they look like big rocks, what structures that serve as habitats for many different types of ocean life are actually alive?
Here are the choices:
A. natural reefs
B. coral reefs
C. southern reefs
D. new forming reefs | Coral reefs ( Figure below ) look like big rocks, but they are actually alive. They are built from cnidarians called corals. The corals are sessile (non-moving) polyps that can use their tentacles to feed on ocean creatures that pass by. Their skeletons are made up of calcium carbonate, which is also known as limestone. Over long periods of time, their skeletons build on each other to produce large structures known as coral reefs. Coral reefs are important habitats for many different types of ocean life. | B: coral reefs. |
What type of reactions are chemical reactions that release energy?
Here are the choices:
A. sulfuric reactions
B. exothermic reactions
C. ozonic reactions
D. biochemical reactions | Chemical reactions that release energy are called exothermic reactions . An example is the combustion of methane described at the beginning of this lesson. In organisms, exothermic reactions are called catabolic reactions . Catabolic reactions break down molecules into smaller units. An example is a decomposition reaction, such as the breakdown of glucose molecules for energy. Exothermic reactions can be represented by the general chemical equation:. | B: exothermic reactions. |
Fossil fuels and coal are examples of what kind of resources?
Here are the choices:
A. reusable
B. renewable
C. valuable
D. nonrenewable | Nonrenewable resources exist in fixed amounts. They can be used up. Examples include fossil fuels such as coal. | D: nonrenewable. |
What type of compound contains atoms of two or more different elements in its ring structure?
Here are the choices:
A. heterocyclic
B. aldehyde
C. hydrocarbon
D. polymer | In some amines, the nitrogen atom replaces a carbon atom in an aromatic hydrocarbon. Pyridine (Figure 20.17) is one such heterocyclic amine. A heterocyclic compound contains atoms of two or more different elements in its ring structure. | A: heterocyclic. |
What is formed when atoms of different elements combine in a chemical reaction?
Here are the choices:
A. dust
B. toxins
C. crystals
D. compounds | For each of the following situations, tell whether the rate of the reaction would increase or decrease, and explain your answer in terms of collision theory. The concentration of a reactant is doubled. | D: compounds. |
What type of electricity is formed when a negative charge builds up and are transferred?
Here are the choices:
A. static electricity
B. alternating current
C. direct current
D. neutron energy | Static electricity is a buildup of electric charges on objects. Charges build up when negative electrons are transferred from one object to another. The object that gives up electrons becomes positively charged, and the object that accepts the electrons becomes negatively charged. This can happen in several ways. | A: static electricity. |
What important liquid is stored throughout the earth in the oceans, underground, and in ice?
Here are the choices:
A. air
B. water
C. oil
D. lava | Water cycling is extremely important to ecosystem dynamics. Water has a major influence on climate and, thus, on the environments of ecosystems, some located on distant parts of the Earth. Most of the water on Earth is stored for long periods in the oceans, underground, and as ice. Figure 46.13 illustrates the average time that an individual water molecule may spend in the Earth’s major water reservoirs. Residence time is a measure of the average time an individual water molecule stays in a particular reservoir. A large amount of the Earth’s water is locked in place in these reservoirs as ice, beneath the ground, and in the ocean, and, thus, is unavailable for short-term cycling (only surface water can evaporate). | B: water. |
What results when a warm air mass runs into a cold air mass?
Here are the choices:
A. warm front
B. rough front
C. dry front
D. cool front | When a warm air mass runs into a cold air mass, it creates a warm front ( Figure below ). The warm air mass is moving faster than the cold air mass. The warm air mass then flows up over the cold air mass. As the warm air rises, it cools. This brings about clouds and sometimes light precipitation. Warm fronts move slowly and cover a wide area. After a warm front passes, the warm air mass behind it brings warmer temperatures. The warm air is also likely to be more humid. | A: warm front. |
Which type of double bond has a sigma bond and a pi bond?
Here are the choices:
A. carbon-oxygen bond
B. sodium - oxygen bond
C. Covalent Bonds
D. dioxide - oxygen bond | Has a double-bonded carbon-oxygen bond (one sigma bond and one pi bond). The carbon to which the oxygen is attached has one hydrogen atom connected to it. | A: carbon-oxygen bond. |
Has the average annual temperature on earth been rising or falling for the past 100 years?
Here are the choices:
A. rising
B. unchanged
C. fluctuating
D. falling | The average annual temperature on Earth has been rising for the past 100 years. | A: rising. |
The majoirty of modern gymnosperms belong to what group, which includes pine trees?
Here are the choices:
A. Pinophytes
B. clusters
C. stems
D. conifers | There are only about 1,000 living species of gymnosperms, whereas there are hundreds of thousands of living species of angiosperms. Living gymnosperms are typically classified in the divisions described in the Table below . Most modern gymnosperms are trees with woody trunks. The majority are conifers such as pine trees. | D: conifers. |
A circuit must be what in order for electric devices such as light bulbs to work?
Here are the choices:
A. cyclical
B. down
C. closed
D. open | A circuit must be closed for electric devices such as light bulbs to work. The arrows in the diagram show the direction in which electrons flow through the circuit. The current is considered to flow in the opposite direction. | C: closed. |
What type of radiation from the sun reaches earth across space striking everything on earth’s surface?
Here are the choices:
A. static
B. particle
C. electromagnetic
D. seismic | Electromagnetic radiation from the sun reaches Earth across space. It strikes everything on Earth’s surface, including these volleyball players. | C: electromagnetic. |
What happens if a catalyst runs out?
Here are the choices:
A. reaction slows
B. reaction increases
C. variety slows
D. variety increases | Chemistry in Everyday Life Transition Metal Catalysts One of the most important applications of transition metals is as industrial catalysts. As you recall from the chapter on kinetics, a catalyst increases the rate of reaction by lowering the activation energy and is regenerated in the catalytic cycle. Over 90% of all manufactured products are made with the aid of one or more catalysts. The ability to bind ligands and change oxidation states makes transition metal catalysts well suited for catalytic applications. Vanadium oxide is used to produce 230,000,000 tons of sulfuric acid worldwide each year, which in turn is used to make everything from fertilizers to cans for food. Plastics are made with the aid of transition metal catalysts, along with detergents, fertilizers, paints, and more (see Figure 19.26). Very complicated pharmaceuticals are manufactured with catalysts that are selective, reacting with one specific bond out of a large number of possibilities. Catalysts allow processes to be more economical and more environmentally friendly. Developing new catalysts and better understanding of existing systems are important areas of current research. | A: reaction slows. |
What type of mammals are humans?
Here are the choices:
A. marsupial mammals
B. respiratory mammals
C. placental mammals
D. somatic mammals | Human beings are mammals. Like other mammals, we have hair and mammary glands. The subclass in which the human species is classified is the placental mammals. | C: placental mammals. |
The shape of the path of an object undergoing projectile motion in two dimensions is a what?
Here are the choices:
A. radius
B. parabola
C. circle
D. orbit | The shape of the path of an object undergoing projectile motion in two dimensions is a parabola. | B: parabola. |
The earliest cells were called what?
Here are the choices:
A. prokaryotes
B. eukaryotes
C. carbohydrates
D. microcytes | The first organisms were made of only one cell ( Figure below ). The earliest cells were prokaryotes . Prokaryotic cells are surrounded by a cell membrane, but they do not have a nucleus. The cells got their nutrients directly from the water. The cells needed to use these nutrients to live and grow. | A: prokaryotes. |
Protists are the simplest of what?
Here are the choices:
A. fungi
B. prokaryotes
C. eukaryotes
D. plants | Protists are the simplest eukaryotes. They are easiest to define by what they are not. Protists are not animals, plants, or fungi. | C: eukaryotes. |
The measure of magnetic fields is named after a serbian physicist. what is his name?
Here are the choices:
A. Albert Einstein
B. nikola tesla
C. Niels Bohr
D. Carl Sagan | For static electric charges, the electromagnetic force is manifested by the Coulomb electric force alone. If charges are moving, an additional force emerges, called magnetism. The century realization that electricity and magnetism are dual aspects of the same force completely changed our understanding of the world we live in. Insights due to Ampere, Gauss, and Maxwell led to the understanding that moving charges – electric currents – create magnetic fields. Varying magnetic fields create electric fields. Thus a loop of wire in a changing magnetic field will have current induced in it. This is called electromagnetic induction. Magnetic fields are usually denoted by the letter and are measured in Teslas, in honor of the Serbian physicist Nikola Tesla. | B: nikola tesla. |
Radon (rn) is a radioactive gas formed by the decay of naturally occurring uranium in rocks such as granite. it tends to collect in the basements of houses and poses a significant health risk if present in indoor air. many states now require that houses be tested for radon before they are what?
Here are the choices:
A. sold
B. seen
C. built
D. modified | M = dRTP Exercise Radon (Rn) is a radioactive gas formed by the decay of naturally occurring uranium in rocks such as granite. It tends to collect in the basements of houses and poses a significant health risk if present in indoor air. Many states now require that houses be tested for radon before they are sold. Calculate the density of radon at 1.00 atm pressure and 20°C and compare it with the density of nitrogen gas, which constitutes 80% of the atmosphere, under the same conditions to see why radon is found in basements rather than in attics. Answer: radon, 9.23 g/L; N2, 1.17 g/L A common use of Equation 10.23 is to determine the molar mass of an unknown gas by measuring its density at a known temperature and pressure. This method is particularly useful in identifying a gas that has been produced in a reaction, and it is not difficult to carry out. A flask or glass bulb of known volume is carefully dried, evacuated, sealed, and weighed empty. It is then filled with a sample of a gas at a known temperature and pressure and reweighed. The difference in mass between the two readings is the mass of the gas. The volume of the flask is usually determined by weighing the flask when empty and when filled with a liquid of known density such as water. The use of density measurements to calculate molar masses is illustrated in Example 10. | A: sold. |
What state of matter takes neither the shape nor the volume of its container?
Here are the choices:
A. hot
B. liquid
C. gas
D. solid | All three containers contain a substance with the same mass, but the substances are in different states. In the left-hand container, the substance is a gas, which has spread to fill its container. It takes both the shape and volume of the container. In the middle container, the substance is a liquid, which has spread to take the shape of its container but not the volume. In the right-hand container, the substance is a solid, which takes neither the shape nor the volume of its container. | D: solid. |
Force times distance is the equation for what?
Here are the choices:
A. work
B. power
C. speed
D. gravity | Work is directly related to both the force applied to an object and the distance the object moves. It can be represented by the equation: Work = Force × Distance. | A: work. |
What is the name for a series of changes in the reproductive system of mature females that repeats every month on average?
Here are the choices:
A. periodic table
B. menstrual cycle
C. puberty
D. urinary cycle | Egg production in the ovary is part of the menstrual cycle. The menstrual cycle is a series of changes in the reproductive system of mature females that repeats every month on average. These changes include the development of an egg and follicle in the ovary. | B: menstrual cycle. |
What is the name of the iron-containing oxygen-transport protein in the red blood cells of all vertebrates?
Here are the choices:
A. ferric acid
B. plasma
C. platelet
D. hemoglobin | Hemoglobin is the iron-containing oxygen-transport protein in the red blood cells of all vertebrates. The hemoglobin molecule is an assembly of four globular protein subunits, each tightly associated with a non-protein heme group. The heme group binds to the iron ion. The most common hemoglobin is hemoglobin A, a tetramer consisting of two alpha and two beta subunits, denoted as α2β2. | D: hemoglobin. |
What is the active ingredient in household bleach?
Here are the choices:
A. chlorine
B. oxygen
C. iodine
D. magnesium | Chlorine is the active ingredient in household bleach. It removes stains from clothes. It can also be used to disinfect countertops and other surfaces. | A: chlorine. |
What are the membrane-bound organelles that are usually larger than vesicles and can have secretory, excretory, and storage functions?
Here are the choices:
A. nucleolus
B. vacuoles
C. tubules
D. ribosomes | Vacuoles are membrane-bound organelles that can have secretory, excretory, and storage functions. They are usually larger than vesicles. | B: vacuoles. |
What broad category of animals is primarily ectothermic and covered with scales that facilitate swimming?
Here are the choices:
A. fish
B. armadillo
C. deer
D. turtles | Fish show great diversity in body size. They range in length from about 8 millimeters (0.3 inches) to 16 meters (about 53 feet). Most are ectothermic and covered with scales. Scales protect fish from predators and parasites and reduce friction with the water. Multiple, overlapping scales provide a flexible covering that allows fish to move easily while swimming. | A: fish. |
What has two chains of nucleotides, one more than rna?
Here are the choices:
A. mna
B. dna
C. fna
D. gna | RNA consists of just one chain of nucleotides. DNA consists of two chains. Nitrogen bases on the two chains of DNA form hydrogen bonds with each other. Hydrogen bonds are relatively weak bonds that form between a positively charged hydrogen atom in one molecule and a negatively charged atom in another molecule. Hydrogen bonds form only between adenine and thymine, and between guanine and cytosine. These bonds hold the two chains together and give DNA is characteristic double helix, or spiral, shape. | B: dna. |
The axon terminates on muscle fibers at the neuromuscular junction. acetylcholine is released at this specialized synapse, which causes the muscle action potential to begin, following a large potential known as an end plate potential. when the lower motor neuron excites the muscle fiber, it contracts. all of this occurs in a fraction of a second, but this story is the basis of how this functions?
Here are the choices:
A. cardiovascular system
B. muscular system
C. nervous system
D. respiratory system | described in the chapter on muscle tissue, an action potential travels along the motor neuron axon into the periphery. The axon terminates on muscle fibers at the neuromuscular junction. Acetylcholine is released at this specialized synapse, which causes the muscle action potential to begin, following a large potential known as an end plate potential. When the lower motor neuron excites the muscle fiber, it contracts. All of this occurs in a fraction of a second, but this story is the basis of how the nervous system functions. | C: nervous system. |
Misconceptions about what theory contribute to the controversy that still surrounds this fundamental principle of biology?
Here are the choices:
A. darwin on evolution
B. brain of evolution
C. theory of evolution
D. cycle of evolution | Today, evolution is still questioned by some people. Often, people who disagree with the theory of evolution do not really understand it. For example, some people think that the theory of evolution explains how life on Earth first began. In fact, the theory explains only how life changed after it first appeared. Some people think the theory of evolution means that humans evolved from modern apes. In fact, the theory suggests humans and modern apes have a common ancestor that lived several million years ago. These and other misconceptions about evolution contribute to the controversy that still surrounds this fundamental principle of biology. | C: theory of evolution. |
What device is used to stop a current in a circuit?
Here are the choices:
A. a signal
B. a mirror
C. a switch
D. a valve | Understand current as it passes through a series circuit. | C: a switch. |
What oily substance prevents the hair and skin of living things from drying out?
Here are the choices:
A. sebum
B. pancreatic enzymes
C. pus
D. progesterone | Sebaceous glands are commonly called oil glands. They produce an oily substance called sebum. Sebum is secreted into hair follicles. Then it makes its way along the hair shaft to the surface of the skin. Sebum waterproofs the hair and skin and helps prevent them from drying out. | A: sebum. |
What two types of communication do both humans and birds use primarily?
Here are the choices:
A. visual and auditory
B. interaction and auditory
C. material and auditory
D. sensual and auditory | A: visual and auditory. | |
Eggs are produced in what organs and, upon fertilization, develop in what other organ?
Here are the choices:
A. ovaries, uterus
B. fallopian tubes, ovaries
C. cervix, ovaries
D. uterus, vagina | A: ovaries, uterus. | |
The first line of defense includes mechanical, chemical, and which other barrier?
Here are the choices:
A. physical
B. biological
C. surgical
D. independent | The first line of defense includes mechanical, chemical, and biological barriers. | B: biological. |
What is another term for nearsightedness?
Here are the choices:
A. anemia
B. hypoxia
C. astigmatism
D. myopia | Nearsightedness, or myopia, is the condition in which nearby objects are seen clearly, but distant objects appear blurry. The Figure below shows how it occurs. The eyeball is longer (from front to back) than normal. This causes images to be focused in front of the retina instead of on the retina. Myopia can be corrected with concave lenses. The lenses focus images farther back in the eye, so they fall on the retina instead of in front of it. | D: myopia. |
Because all animals require an external source of what, they are called heterotrophic?
Here are the choices:
A. food
B. water
C. energy
D. fuel | 27.1 | Features of the Animal Kingdom By the end of this section, you will be able to: • List the features that distinguish the kingdom Animalia from other kingdoms • Explain the processes of animal reproduction and embryonic development • Describe the roles that Hox genes play in development Even though members of the animal kingdom are incredibly diverse, most animals share certain features that distinguish them from organisms in other kingdoms. All animals are eukaryotic, multicellular organisms, and almost all animals have a complex tissue structure with differentiated and specialized tissues. Most animals are motile, at least during certain life stages. All animals require a source of food and are therefore heterotrophic, ingesting other living or dead organisms; this feature distinguishes them from autotrophic organisms, such as most plants, which synthesize their own nutrients through photosynthesis. As heterotrophs, animals may be carnivores, herbivores, omnivores, or parasites (Figure 27.2ab). Most animals reproduce sexually, and the offspring pass through a series of developmental stages that establish a determined and fixed body plan. The body plan refers to the morphology of an animal, determined by developmental cues. | A: food. |
What causes blue litmus to turn red?
Here are the choices:
A. acid
B. oxygen
C. carbon
D. base | Acids change the color of certain acid-base indicators. Two common indicators are litmus and phenolphthalein. Blue litmus turns red in the presence of an acid, while phenolphthalein turns colorless. | A: acid. |
When fossil fuel is burned the chemical energy is converted into what?
Here are the choices:
A. atmospheric energy
B. thermal energy
C. kinetic energy
D. natural energy | Watching movies, eating hot popcorn, and many other activities depend on electrical energy. Most electrical energy comes from the burning of fossil fuels, which contain stored chemical energy. When fossil fuels are burned, the chemical energy changes to thermal energy and the thermal energy is then used to generate electrical energy. These are all examples of energy conversion. Energy conversion is the process in which one kind of energy changes into another kind. When energy changes in this way, the energy isn’t used up or lost. The same amount of energy exists after the conversion as before. Energy conversion obeys the law of conservation of energy, which states that energy cannot be created or destroyed. | B: thermal energy. |
What two activities are especially important when a number of local populations are linked, forming a metapopulation?
Here are the choices:
A. family reunions and emigration
B. immigration and emigration
C. immigration and family reunions
D. flow and emigration | B: immigration and emigration. | |
What is the physical environment in which a species lives and to which it has adapted?
Here are the choices:
A. land mass
B. ecosystem
C. habitat
D. farmland | Another important aspect of a species’ niche is its habitat. Habitat is the physical environment in which a species lives and to which it has adapted. Features of a habitat depend mainly on abiotic factors, such as temperature and rainfall. These factors influence the traits of the organisms that live there. | C: habitat. |
What kind of tests may detect substances associated with particular disorders?
Here are the choices:
A. hormonal
B. genetic
C. biochemical
D. electrical | C: biochemical. | |
Scientists think the solar system formed from a big cloud of gas and dust called what?
Here are the choices:
A. supernova
B. nebula
C. Oort cloud
D. comet | Scientists think the solar system formed from a big cloud of gas and dust, called a nebula . This is the solar nebula hypothesis. The nebula was made mostly of hydrogen and helium. There were heavier elements too. Gravity caused the nebula to contract ( Figure below ). | B: nebula. |
What are the largest phylum of the animal kingdom?
Here are the choices:
A. arthropods
B. Crustacea
C. Pycnogonida
D. Chelicerata | Two chemical species combine to produce a new compound. The general expression for this reaction is A + B → C. | A: arthropods. |
What is the name for a material that prevents the transfer of heat energy?
Here are the choices:
A. thermal condenser
B. physical insulator
C. thermal insulator
D. structure insulator | Another example of a thermal insulator is pictured in the Figure below . The picture shows fluffy pink insulation inside the attic of a home. Like the down filling in a snowsuit, the insulation traps a lot of air. The insulation helps to prevent the transfer of thermal energy into the house on hot days and out of the house on cold days. Other materials that are thermal insulators include plastic and wood. That’s why pot handles and cooking utensils are often made of these materials. Notice that the outside of the toaster pictured in the opening image is made of plastic. The plastic casing helps prevent the transfer of thermal energy from the heating element inside to the outer surface of the toaster where it could cause burns. You can learn more about thermal insulators at this URL: http://www. school-for-champions. com/science/thermal_insulation. htm . | C: thermal insulator. |
What is a rock exposed to if it's undergoing metamorphism?
Here are the choices:
A. gravity and precipitation
B. heat and pressure
C. time and energy
D. humidity and pressure | Metamorphism. This long word means “to change form. “ A rock undergoes metamorphism if it is exposed to extreme heat and pressure within the crust. With metamorphism, the rock does not melt all the way. The rock changes due to heat and pressure. A metamorphic rock may have a new mineral composition and/or texture. | B: heat and pressure. |
Water infiltrates the ground because soil and rock may have air spaces between the grains. these pores, or tiny holes, result in the rock's what?
Here are the choices:
A. energy
B. porosity
C. shine
D. sheen | Identify features caused by groundwater erosion and deposition. | B: porosity. |
Work is done only if a force is exerted in the direction of what?
Here are the choices:
A. wind
B. motion
C. gravity
D. north | Work is done only if a force is exerted in the direction of motion. If the motion is perpendicular to the force, no work has been done. If the force is at an angle to the motion, then the component of the force in the direction of the motion is used to determine the work done. | B: motion. |
What is the smallest independently functioning unit of a living organism?
Here are the choices:
A. proteins
B. cell
C. molecule
D. atom | A cell is the smallest independently functioning unit of a living organism. Even bacteria, which are extremely small, independently-living organisms, have a cellular structure. Each bacterium is a single cell. All living structures of human anatomy contain cells, and almost all functions of human physiology are performed in cells or are initiated by cells. A human cell typically consists of flexible membranes that enclose cytoplasm, a water-based cellular fluid together with a variety of tiny functioning units called organelles. In humans, as in all organisms, cells perform all functions of life. A tissue is a group of many similar cells (though sometimes composed of a few related types) that work together to perform a specific function. An organ is an anatomically distinct structure of the body composed of two or more tissue types. Each organ performs one or more specific physiological functions. An organ system is a group of organs that work together to perform major functions or meet physiological needs of the body. This book covers eleven distinct organ systems in the human body (Figure 1.4 and Figure 1.5). Assigning organs to organ systems can be imprecise since organs that “belong” to one system can also have functions integral to another system. In fact, most organs contribute to more than one system. | B: cell. |
All animals have specialized types of what basic structures, which can then do different jobs?
Here are the choices:
A. muscles
B. proteins
C. cells
D. atoms | Animals are multicellular eukaryotes in the Animal Kingdom. All animals are heterotrophs. They eat other living things because they can’t make their own food. All animals also have specialized cells that can do different jobs. Most animals have higher levels of organization as well. They may have specialized tissues, organs, and even organ systems. Having higher levels of organization allows animals to perform many complex functions. For a visual introduction to what makes a living thing an animal, watch this short video: https://www. youtube. com/watch?v=DXPhJUHooP8 . | C: cells. |
What term describes the number of items in a given area or volume?
Here are the choices:
A. fraction
B. alkalinity
C. density
D. concentration | In its most general form, concentration describes the number of items in a given area or volume. The units generally depend on the types of items being counted. For example, if we were to calculate the concentration of people that live in a city, we would divide the total number of people by the area. If we measured the area in square miles, the units of concentration for this measurement would be people per square mile. Or, we could determine the concentration of fish in a lake by dividing the total number of fish by the volume of the lake. If we measure the volume in cubic meters, the concentration would have units of fish per cubic meter. | D: concentration. |
Birds are known for flying south in the winter to avoid what?
Here are the choices:
A. solar radiation
B. rain
C. hurricanes
D. cold weather | D: cold weather. | |
The root system is usually anchored by one main root developed from what?
Here are the choices:
A. organisms radicle
B. sperm radicle
C. nuclei radicle
D. embryonic radicle | Eudicots Eudicots, or true dicots, are characterized by the presence of two cotyledons. Veins form a network in leaves. Flower parts come in four, five, or many whorls. Vascular tissue forms a ring in the stem. (In monocots, vascular tissue is scattered in the stem. ) Eudicots can be herbaceous (like dandelions or violets), or produce woody tissues. Most eudicots produce pollen that is trisulcate or triporate, with three furrows or pores. The root system is usually anchored by one main root developed from the embryonic radicle. Eudicots comprise two-thirds of all flowering plants. Many species seem to exhibit characteristics that belong to either group; therefore, the classification of a plant as a monocot or a eudicot is not always clearly evident (Table 14.1). | D: embryonic radicle. |
What type of learning is done from past experiences and reasoning?
Here are the choices:
A. rational learning
B. transformation learning
C. consequence learning
D. insight learning | Insight learning is learning from past experiences and reasoning. It usually involves coming up with new ways to solve problems. Insight learning generally happens quickly. An animal has a sudden flash of insight. Insight learning requires relatively great intelligence. Human beings use insight learning more than any other species. They have used their intelligence to solve problems ranging from inventing the wheel to flying rockets into space. | D: insight learning. |
Where is the pituitary gland?
Here are the choices:
A. lung
B. thyroid
C. heart
D. brain | The regulation of Leydig cell production of testosterone begins outside of the testes. The hypothalamus and the pituitary gland in the brain integrate external and internal signals to control testosterone synthesis and secretion. The regulation begins in the hypothalamus. Pulsatile release of a hormone called gonadotropin-releasing hormone (GnRH) from the hypothalamus stimulates the endocrine release of hormones from the pituitary gland. Binding of GnRH to its receptors on the anterior pituitary gland stimulates release of the two gonadotropins: luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These two hormones are critical for reproductive function in both men and women. In men, FSH binds predominantly to the Sertoli cells within the seminiferous tubules to promote spermatogenesis. FSH also stimulates the Sertoli cells to produce hormones called inhibins, which function to inhibit FSH release from the pituitary, thus reducing testosterone secretion. These polypeptide hormones correlate directly with Sertoli cell function and sperm number; inhibin B can be used as a marker of spermatogenic activity. In men, LH binds to receptors on Leydig cells in the testes and upregulates the production of testosterone. A negative feedback loop predominantly controls the synthesis and secretion of both FSH and LH. Low blood concentrations of testosterone stimulate the hypothalamic release of GnRH. GnRH then stimulates the anterior pituitary to secrete LH into the bloodstream. In the testis, LH binds to LH receptors on Leydig cells and stimulates the release of testosterone. When concentrations of testosterone in the blood reach a critical threshold, testosterone itself will bind to androgen receptors on both the hypothalamus and the anterior pituitary, inhibiting the synthesis and secretion of GnRH and LH, respectively. When the blood concentrations of testosterone once again decline, testosterone no longer interacts with the receptors to the same degree and GnRH and LH are once again secreted, stimulating more testosterone production. This same process occurs with FSH and inhibin to control spermatogenesis. | D: brain. |
Which fungi eaten by people all over the world?
Here are the choices:
A. algae
B. fruits
C. mushrooms
D. legumes | Mushrooms are fungi that are eaten by people all over the globe. | C: mushrooms. |
The outermost layer of the leaf is the epidermis; it is present on both sides of the leaf and is called the upper and lower epidermis, respectively. botanists call the upper side the adaxial surface (or adaxis) and the lower side this?
Here are the choices:
A. anterior surface
B. abaxial surface (or abaxis)
C. dorsal surface
D. posterior surface | Leaf Structure and Function The outermost layer of the leaf is the epidermis; it is present on both sides of the leaf and is called the upper and lower epidermis, respectively. Botanists call the upper side the adaxial surface (or adaxis) and the lower side the abaxial surface (or abaxis). The epidermis helps in the regulation of gas exchange. It contains stomata (Figure 30.24): openings through which the exchange of gases takes place. Two guard cells surround each stoma, regulating its opening and closing. | B: abaxial surface (or abaxis). |
A small quake preceding a large quake is called what?
Here are the choices:
A. foreshock
B. aftershock
C. warning shock
D. preshock | There are sometimes signs that a large earthquake is coming. There may be small quakes, called foreshocks . These can occur a few seconds to a few weeks before a major quake. Unfortunately, foreshocks are not very useful for predicting large earthquakes. Many quakes do not have foreshocks. Also, small earthquakes are not necessarily followed by a large earthquake. | A: foreshock. |
What do winter storms develop from at higher latitudes?
Here are the choices:
A. humidity
B. cyclones
C. clouds
D. temperatures | Winter storms develop from cyclones at higher latitudes. They include blizzards and lake-effect snow storms. | B: cyclones. |
What is the only substance on earth that is present in all three states of matter?
Here are the choices:
A. air
B. carbon
C. mercury
D. water | Water is the only substance on Earth that is present in all three states of matter. This means that water is present as a solid, liquid, and gas. Earth is the only planet where water is present in all three states. All three phases may be present in a single location or in a region. The three phases are solid (ice or snow), liquid (water), and gas ( water vapor ). See ice, water, and clouds pictured below ( Figure below ). | D: water. |
What is essential for forming new genes?
Here are the choices:
A. enough chromosomes
B. enough mutations
C. chromosome deversity
D. large mutations | It is believed that large mutations form new genes. Mutations that duplicate large sections of DNA are a major source of genetic material for new genes. It is thought that tens to hundreds of genes are duplicated in animal genomes every million years. Most genes belong to larger families of genes of shared ancestry. These gene families have domains within the protein with a particular and independent function. These domains have corresponding conserved regions within their genes. It is through duplication mutations that such gene families formed. Genetic recombination after duplication of different domains forms new combinations of domains with new functions. For example, the human eye uses four genes to make structures that sense light: three for color vision and one for night vision; all four arose from a single ancestral gene. | D: large mutations. |
What is fluid friction with air called?
Here are the choices:
A. gravity
B. air resistance
C. wind resistance
D. buoyancy | Types of friction include static friction, sliding friction, rolling friction, and fluid friction. Fluid friction with air is called air resistance. | B: air resistance. |
Plants produce their own sugars and other food molecules through what process?
Here are the choices:
A. spermatogenesis
B. glycolysis
C. photosynthesis
D. hydrogenesis | C: photosynthesis. | |
What do fission reactors use to slow down the neutrons?
Here are the choices:
A. inertia
B. brake
C. moderator
D. control | U-235 nuclei can capture neutrons and disintegrate more efficiently if the neutrons are moving slower than the speed at which they are released. Fission reactors use a moderator surrounding the fuel rods to slow down the neutrons. Water is not only a good coolant but also a good moderator, so a common type of fission reactor has the fuel core submerged in a huge pool of water. This type of reactor is called a light water reactor or LWR. All public electricity generating fission reactors in the United States are LWRs. | C: moderator. |
What term is used to describe an unusual sound coming from the heart that is caused by the turbulent flow of blood?
Here are the choices:
A. garble
B. whisper
C. music
D. murmur | The term murmur is used to describe an unusual sound coming from the heart that is caused by the turbulent flow of blood. Murmurs are graded on a scale of 1 to 6, with 1 being the most common, the most difficult sound to detect, and the least serious. The most severe is a 6. Phonocardiograms or auscultograms can be used to record both normal and abnormal sounds using specialized electronic stethoscopes. During auscultation, it is common practice for the clinician to ask the patient to breathe deeply. This procedure not only allows for listening to airflow, but it may also amplify heart murmurs. Inhalation increases blood flow into the right side of the heart and may increase the amplitude of right-sided heart murmurs. Expiration partially restricts blood flow into the left side of the heart and may amplify left-sided heart murmurs. Figure 19.30 indicates proper placement of the bell of the stethoscope to facilitate auscultation. | D: murmur. |
Carbon atoms are bonded to as many hydrogen atoms as possible in what type of fatty acids?
Here are the choices:
A. oily
B. super
C. unsaturated
D. saturated | Saturated fatty acids have only single bonds between carbon atoms. As a result, the carbon atoms are bonded to as many hydrogen atoms as possible. In other words, the carbon atoms are saturated with hydrogens. Saturated fatty acids are found in fats. | D: saturated. |
What kind of mouthparts do aphids have?
Here are the choices:
A. chewing mouthparts
B. siphoning mouthparts
C. sponging mouthparts
D. piercing-sucking mouthparts | Some insects, such as aphids, have piercing-sucking mouthparts. Other insects, like grasshoppers, have chewing mouthparts. | D: piercing-sucking mouthparts. |
Sounds, chemicals, and visual cues are examples of what between animals?
Here are the choices:
A. migration
B. procreation
C. circulation
D. communication | For individuals to cooperate, they need to communicate . Animals can communicate with sounds, chemicals, or visual cues. For example, to communicate with sounds, birds sing and frogs croak. Both may be communicating that they are good mates. Ants communicate with chemicals called pheromones . For example, they use the chemicals to mark trails to food sources so other ants can find them. Male dogs use pheromones in urine to mark their territory. They are “telling” other dogs to stay out of their yard. You can see several examples of visual communication in Figure below . | D: communication. |
What is pressure times area equal to?
Here are the choices:
A. density
B. mass
C. force
D. volume | There is a pressure difference when the channel narrows. This pressure difference results in a net force on the fluid: recall that pressure times area equals force. The net work done increases the fluid’s kinetic energy. As a result, the pressure will drop in a rapidly-moving fluid, whether or not the fluid is confined to a tube. There are a number of common examples of pressure dropping in rapidly-moving fluids. Shower curtains have a disagreeable habit of bulging into the shower stall when the shower is on. The high-velocity stream of water and air creates a region of lower pressure inside the shower, and standard atmospheric pressure on the other side. The pressure difference results in a net force inward pushing the curtain in. You may also have noticed that when passing a truck on the highway, your car tends to veer toward it. The reason is the same—the high velocity of the air between the car and the truck creates a region of lower pressure, and the vehicles are pushed together by greater pressure on the outside. (See Figure 12.4. ) This effect was observed as far back as the mid-1800s, when it was found that trains passing in opposite directions tipped precariously toward one another. | C: force. |
What part of the kangaroo helps it balance when it leaps as well as when it sits?
Here are the choices:
A. the spine
B. the tail
C. the pouch
D. large feet | B: the tail. | |
What is the evolutionary history of a group of related organisms called?
Here are the choices:
A. ancestry
B. superfamily
C. lineage
D. phylogeny | Linnaeus classified organisms based on obvious physical traits. Basically, organisms were grouped together if they looked alike. After Darwin published his theory of evolution in the 1800s, scientists looked for a way to classify organisms that showed phylogeny. Phylogeny is the evolutionary history of a group of related organisms. It is represented by a phylogenetic tree , like the one in Figure below . | D: phylogeny. |
What are specialized cells in the brain that monitor the concentration of solutes in the blood called?
Here are the choices:
A. ionconcentrate
B. sporozoans
C. staurikosaurus
D. osmoreceptors | Many marine invertebrates have internal salt levels matched to their environments, making them isotonic with the water in which they live. Fish, however, must spend approximately five percent of their metabolic energy maintaining osmotic homeostasis. Freshwater fish live in an environment that is hypotonic to their cells. These fish actively take in salt through their gills and excrete diluted urine to rid themselves of excess water. Saltwater fish live in the reverse environment, which is hypertonic to their cells, and they secrete salt through their gills and excrete highly concentrated urine. In vertebrates, the kidneys regulate the amount of water in the body. Osmoreceptors are specialized cells in the brain that monitor the concentration of solutes in the blood. If the levels of solutes increase beyond a certain range, a hormone is released that retards water loss through the kidney and dilutes the blood to safer levels. Animals also have high concentrations of albumin, which is produced by the liver, in their blood. This protein is too large to pass easily through plasma membranes and is a major factor in controlling the osmotic pressures applied to tissues. | D: osmoreceptors. |
Bones consist of four types of tissue, compact bone, spongy bone, bone marrow, and what?
Here are the choices:
A. collagen
B. epithelium
C. periosteum
D. plasma | Bones consist of four different types of tissue: periosteum, compact bone, spongy bone, and bone marrow. Ossification gradually changes the cartilage skeleton of the fetus to the bony skeleton of the adult. | C: periosteum. |
During adolescence, what causes most of the changes associated with puberty?
Here are the choices:
A. methane
B. testosterone
C. nicotine
D. estrogen | During adolescence, testosterone causes most of the changes associated with puberty. It causes the reproductive organs to mature. It also causes other adult male traits to develop. For example, it causes the voice to deepen and facial hair to start growing. | B: testosterone. |
What is essential for cellular respiration for all aerobic organisms?
Here are the choices:
A. nitrogen
B. oxygen
C. water
D. carbon | An online guide from the University of Illinois about air masses and fronts is found here: http://ww2010. atmos. uiuc. edu/%28Gh%29/guides/mtr/af/home. rxml . | B: oxygen. |
Breeding in birds occurs through an internal type of what process?
Here are the choices:
A. segmentation
B. stimulation
C. sedimentation
D. fertilization | Breeding in birds is through internal fertilization, where the egg is fertilized inside the female. | D: fertilization. |
In an endothermic reaction, what is absorbed by the reaction?
Here are the choices:
A. food
B. energy
C. fuel
D. atoms | Because energy is a product, energy is given off by the reaction. Therefore, this reaction is exothermic. Because energy is a reactant, energy is absorbed by the reaction. Therefore, this reaction is endothermic. | B: energy. |
What scientist and monk is best known for his experiments with pea plants?
Here are the choices:
A. gregor mendel
B. charles darwin
C. aristotle
D. steiner mendel | Gregor Mendel was born in 1822 and grew up on his parents’ farm in Austria. He did well in school and became a monk. He also went to the University of Vienna, where he studied science and math. His professors encouraged him to learn science through experimentation and to use math to make sense of his results. Mendel is best known for his experiments with the pea plant Pisum sativum (see Figure below ). You can watch a video about Mendel and his research at the following link: http://www. metacafe. com/watch/hl-19246625/milestones_in_science_engineering_gregor_mendel_and_classical_genetics/ . | A: gregor mendel. |
What are structures that protect the coast like barrier islands called?
Here are the choices:
A. fortresses
B. breakwaters
C. domes
D. dunes | Breakwaters are structures that protect the coast like barrier islands. Groins are structures that help prevent longshore drift from eroding a beach. | B: breakwaters. |
What leads to multiple copies of a chromosomal region?
Here are the choices:
A. gene modification
B. duplications (or amplifications )
C. minimilizations
D. subtractions | Duplications (or amplifications ) lead to multiple copies of a chromosomal region, increasing the number of the genes located within that region. Some genes may be duplicated in their entirety. | B: duplications (or amplifications ). |
The larger surface area of leaves allows them to capture more what?
Here are the choices:
A. sunlight
B. chlorophyll
C. pollen
D. molecules | Roots: Support for the Plant Roots are not well preserved in the fossil record; nevertheless, it seems that they did appear later in evolution than vascular tissue. The development of an extensive network of roots represented a significant new feature of vascular plants. Thin rhizoids attached the bryophytes to the substrate. Their rather flimsy filaments did not provide a strong anchor for the plant; neither did they absorb water and nutrients. In contrast, roots, with their prominent vascular tissue system, transfer water and minerals from the soil to the rest of the plant. The extensive network of roots that penetrates deep in the ground to reach sources of water also stabilizes trees by acting as ballast and an anchor. The majority of roots establish a symbiotic relationship with fungi, forming mycorrhizae. In the mycorrhizae, fungal hyphae grow around the root and within the root around the cells, and in some instances within the cells. This benefits the plant by greatly increasing the surface area for absorption. Leaves, Sporophylls, and Strobili A third adaptation marks seedless vascular plants. Accompanying the prominence of the sporophyte and the development of vascular tissue, the appearance of true leaves improved photosynthetic efficiency. Leaves capture more sunlight with their increased surface area. In addition to photosynthesis, leaves play another role in the life of the plants. Pinecones, mature fronds of ferns, and flowers are all sporophylls—leaves that were modified structurally to bear sporangia. Strobili are structures that contain the sporangia. They are prominent in conifers and are known commonly as cones: for example, the pine cones of pine trees. | A: sunlight. |
What is connected to, and dependent on, the gametophyte?
Here are the choices:
A. the chromosomes
B. the sperm
C. the zygote
D. the sporophyte | Following fertilization, the sporophyte forms. The sporophyte is connected to, and dependent on, the gametophyte. | D: the sporophyte. |
After passing through capillaries and being filtered, clean blood leaves what organ through a vein?
Here are the choices:
A. liver
B. heart
C. kidney
D. pancreas | Blood with wastes enters each kidney through an artery, which branches into many capillaries. After passing through capillaries and being filtered, the clean blood leaves the kidney through a vein. | C: kidney. |
What kind of medical intervention seeks to eradicate diseases like polio and measles?
Here are the choices:
A. malnutrition
B. surgical intervention
C. nutrition
D. vaccination | D: vaccination. | |
The ostrich, kiwi, rhea, cassowary, and moa are examples of what kind of birds?
Here are the choices:
A. flightless
B. raptors
C. prehistoric
D. predators | Some birds have lost the ability to fly during the course of their evolution. Several flightless birds are shown in Figure below . They include the ostrich, kiwi, rhea, cassowary, and moa. All of these birds have long legs and are adapted for running. The penguins shown in the figure are also flightless birds, but they have a very different body shape. That’s because they are adapted for swimming rather than running. | A: flightless. |
What occurs when individuals of different species strive for a limited resource in the same area?
Here are the choices:
A. vegetal competition
B. interspecific competition
C. asexual competition
D. intraspecific competition | Interspecific competition happens when individuals of different species strive for a limited resource in the same area. Since any two species have different traits, one species will be able to out-compete the other. One species will be better adapted to its environment, and essentially "win" the competition. The other species will have lower reproductive success and lower population growth, resulting in a lower survival rate. For example, cheetahs and lions feed on similar prey. If prey is limited, then lions may catch more prey than cheetahs. This will force the cheetahs to either leave the area or suffer a decrease in population. | B: interspecific competition. |
Most fungi reproduce asexually by producing what?
Here are the choices:
A. ions
B. spores
C. toxins
D. seeds | Almost all fungi reproduce asexually by producing spores. A fungi spore is a haploid cell produced by mitosis from a haploid parent cell. It is genetically identical to the parent cell. Fungi spores can develop into new haploid individuals without being fertilized. | B: spores. |
Alchemists, as early as the eighth century, knew nitric acid as aqua fortis, which means?
Here are the choices:
A. strong water
B. clean water
C. isolated water
D. applied water | Nitrogen Oxyacids and Salts Nitrogen pentaoxide, N2O5, and NO2 react with water to form nitric acid, HNO3. Alchemists, as early as the eighth century, knew nitric acid (shown in Figure 18.50) as aqua fortis (meaning "strong water"). The acid was useful in the separation of gold from silver because it dissolves silver but not gold. Traces of nitric acid occur in the atmosphere after thunderstorms, and its salts are widely distributed in nature. There are tremendous deposits of Chile saltpeter,. | A: strong water. |
Particles of sand and what other substance are carried by longshore drift?
Here are the choices:
A. magma
B. soil
C. bone
D. rock | Longshore drift carries particles of sand and rock down a coastline. | D: rock. |
Most reptiles reproduce sexually and have what type of fertilization?
Here are the choices:
A. external
B. internal
C. mechanical
D. additional | Most reptiles reproduce sexually and have internal fertilization. | B: internal. |
What is type of substance is formed when water vapor condenses or when ice melts?
Here are the choices:
A. liquid water
B. toxic water
C. gaseous water
D. chemical water | Liquid water is formed when water vapor condenses (i. e. , H 2 O(g) → H 2 O(l) or when ice melts (i. e. , H 2 O(s) → H 2 O(l)). Because water is a molecular substance, it is a poor conductor of electricity in its pure form. However, as we will see later, its conductivity can be improved by the addition of certain substances. Water molecules are polar, and this overall polarity gives rise to many of the properties of water. For example, an interesting effect is seen when water is placed in a static electric field, as shown in the Figure below and the video below. This phenomenon can be explained in terms of the polarity of water molecules. | A: liquid water. |
What occur because solid lithosphere travels on a round planet?
Here are the choices:
A. intraplate earthquakes
B. ejecta earthquakes
C. aeration earthquakes
D. volcanos | Intraplate earthquakes occur because solid lithosphere travels on a round planet. | A: intraplate earthquakes. |
What is the unit of evolution?
Here are the choices:
A. species
B. community
C. biome
D. population | Remember that individuals do not evolve. Their genes do not change over time. The unit of evolution is the population. A population consists of organisms of the same species that live in the same area. In terms of evolution, the population is assumed to be a relatively closed group. This means that most mating takes place within the population. The science that focuses on evolution within populations is population genetics . It is a combination of evolutionary theory and Mendelian genetics. | D: population. |
The boiling points of liquid also correlate to the strength of which forces?
Here are the choices:
A. supramolecular
B. intermolecular
C. gravitational
D. centrifugal | The boiling points of liquid also correlate to the strength of the intermolecular forces. Recall that diethyl ether has weak dispersion forces, which meant that the liquid has a high vapor pressure. The weak forces also mean that it does not require a large an input of energy to make diethyl ether boil and so it has a relatively low normal boiling point of 34.6°C. Water, with its much stronger hydrogen bonding, has a low vapor pressure and a higher normal boiling point of 100°C. | B: intermolecular. |
Vitamin d is made in the skin when it is exposed to what?
Here are the choices:
A. sunlight
B. water
C. darkness
D. dirt | Vitamins are organic compounds that the body needs in small amounts to function properly. Humans need 16 different vitamins. Six of them are listed in Table below . Vitamin D is made in the skin when it is exposed to sunlight. Bacteria that normally live in the gut make vitamins B12 and K. All other vitamins must come from food. The table shows good food sources of the vitamins. | A: sunlight. |
Of the three basic types of radioactive emissions, what particle is the most penetrating?
Here are the choices:
A. gamma
B. neutron
C. beta
D. alpha | The various emissions will differ considerably in their ability to go through matter, known as their penetrating ability . The α-particle has the least penetrating power since it is the largest and slowest emission. It can be blocked by a sheet of paper or a human hand. Beta particles are more penetrating than alpha particles, but can be stopped by a thin sheet of aluminum. Of the three basic types of emissions, gamma particle are the most penetrating. A thick lead shield is required to stop gamma emissions. Positrons represent a special case in that they annihilate when they come in contact with electrons. The collision of a positron and an electron results in the formation of two gamma emissions that go 180 degrees away from each other. | A: gamma. |
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