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The major cause of outdoor air pollution is the burning of?
[ "trees", "trash", "fossil fuels", "charcoal briquettes" ]
C
The major cause of outdoor air pollution is the burning of fossil fuels.
train
sciq
null
What is the ideal mechanical advantage in the single fixed pulley?
[ "2", "zero", "4", "1" ]
D
In the single fixed pulley, only one rope segment pulls up on the load, so the ideal mechanical advantage is 1. In other words, this type of pulley doesn’t increase the force that is applied to it. However, it does change the direction of the force. This allows you to use your weight to pull on one end of the rope and ...
train
sciq
null
What science is the study of matter and the changes it undergoes?
[ "geology", "chemistry", "biology", "astronomy" ]
B
Chemistry is the study of matter and the changes it undergoes.
train
sciq
null
What is driven by the sun's energy and moves water over the surface of earth?
[ "weather cycle", "the water cycle", "tides", "sun cycle" ]
B
The Sun heats some areas more than others, which causes wind. The Sun's energy also drives the water cycle, which moves water over the surface of the Earth. Both wind and water power can be used as renewable resources.
train
sciq
null
What are materials that are poor thermal conductors called?
[ "thermal insulators", "warmth insulators", "pollution insulators", "sunlight insulators" ]
A
Particles of gases are farther apart and have fewer collisions, so they are not good at transferring thermal energy. Materials that are poor thermal conductors are called thermal insulators . Figure below shows several examples. Fluffy yellow insulation inside the roof of a home is full of air. The air prevents the tra...
train
sciq
null
Balanced chemical reactions are balanced in what?
[ "atoms", "molecular bonds", "terms of moles", "electrical charge" ]
C
Balanced chemical reactions are balanced in terms of moles.
train
sciq
null
The autonomic nervous system serves as the relay between what and the internal organs?
[ "peripheral nervous system", "somatic system", "hormones", "central nervous system" ]
D
The autonomic nervous system serves as the relay between the CNS and the internal organs. It controls the lungs, the heart, smooth muscle, and exocrine and endocrine glands. The autonomic nervous system controls these organs largely without conscious control; it can continuously monitor the conditions of these differen...
train
sciq
null
The role that a particular species plays in its ecosystem is also known as what?
[ "market", "type", "unique", "niche" ]
D
Niche is the role that a particular species plays in its ecosystem. This role includes all the ways that the species interacts with the biotic and abiotic factors in the ecosystem.
train
sciq
null
What element has the atomic number 16?
[ "sulfur", "oxygen", "neon", "helium" ]
A
train
sciq
null
Name the most famous satellite of the earth?
[ "the moon", "skylab", "demos", "sputnik" ]
A
train
sciq
null
What is the minimum number of loops a circuit can have?
[ "1", "3", ".1", "2" ]
A
An electric circuit consists of at least one closed loop through which electric current can flow. Every circuit has a voltage source such as a battery and a conductor such as metal wire. A circuit may have other parts as well, such as lights and switches. In addition, a circuit may consist of one loop or two loops.
train
sciq
null
What type of organism is algae?
[ "virus", "bacteria (cyanobacteria)", "amoeba", "yeast" ]
B
Describe why algae is a good source of biofuel.
train
sciq
null
When water slows down, it starts depositing sediment, starting with which particles first?
[ "finest", "lightest", "largest", "smallest" ]
C
How water transports particles depends on their size. When water slows down, it starts depositing sediment, starting with the largest particles first.
train
sciq
null
Because they control many cell activities - as well as being controlled by feedback mechanisms - what substances are very important for homeostasis?
[ "enzymes", "hormones", "acids", "proteins" ]
B
Hormones control many cell activities, so they are very important for homeostasis. But what controls the hormones themselves? Most hormones are regulated by feedback mechanisms. A feedback mechanism is a loop in which a product feeds back to control its own production. Most hormone feedback mechanisms involve negative ...
train
sciq
null
Contraction of what large, sheet-like muscle results in inhalation?
[ "uterus", "diaphragm", "deltoid", "pelvic floor" ]
B
Inhaling is an active movement that results from the contraction of a muscle called the diaphragm. The diaphragm is large, sheet-like muscle below the lungs (see Figure below ). When the diaphragm contracts, the ribcage expands and the contents of the abdomen move downward. This results in a larger chest volume, which ...
train
sciq
null
What type of ionic compound is formed from acid and bases reacting with each other?
[ "isolated", "common", "dry", "salt" ]
D
Acids have some properties in common. They turn litmus, a plant extract, red. They react with some metals to give off H2 gas. They react with carbonate and hydrogen carbonate salts to give off CO2 gas. Acids that are ingested typically have a sour, sharp taste. (The name acid comes from the Latin word acidus, meaning “...
train
sciq
null
The iron ion used to bind oxygen is on what type of "ring"?
[ "DNA ring", "reagent ring", "porphyrin ring", "petrarchan ring" ]
C
The yellow subunits are identical in structure, as are the gray subunits. A smaller organic structure called a porphyrin ring is attached to each protein subunit and contains the iron ion used to bind oxygen.
train
sciq
null
In police radar, a radar gun sends out short bursts of which waves?
[ "soundwaves", "photons", "microwaves", "electrodes" ]
C
Radar stands for ra dio d etection and r anging. In police radar, a radar gun sends out short bursts of microwaves. The microwaves reflect back from oncoming vehicles and are detected by a receiver in the radar gun. The frequency of the reflected waves is used to compute the speed of the vehicles. Radar is also used fo...
train
sciq
null
Oxides of small, highly charged ions of what type tend to be acidic?
[ "plastic", "steel", "liquid", "metal" ]
D
Summary The transition metals are characterized by partially filled d subshells in the free elements and cations. The ns and (n − 1)d subshells have similar energies, so small influences can produce electron configurations that do not conform to the general order in which the subshells are filled. In the secondand thir...
train
sciq
null
A lewis acid is a substance that accepts a pair of electrons to form what?
[ "covalent bond", "ambivalent bond", "accretion bond", "functionality bond" ]
A
Gilbert Lewis (1875-1946) proposed a third theory of acids and bases that is even more general than either the Arrhenius or Brønsted-Lowry theories. A Lewis acid is a substance that accepts a pair of electrons to form a covalent bond. A Lewis base is a substance that donates a pair of electrons to form a covalent bond....
train
sciq
null
What is the amount of force pushing against a given area?
[ "energy", "power", "pressure", "inertia" ]
C
Pressure is defined as the amount of force pushing against a given area. How much pressure a gas exerts depends on the amount of gas. The more gas particles there are, the greater the pressure.
train
sciq
null
What is another word for seed plants?
[ "gymnosperm", "phyla", "protosperm", "echinoderm" ]
A
The most basic division is between nonvascular plants and vascular plants . Vascular plants are further divided into those that reproduce without seeds and those that reproduce with seeds. Seed plants, in turn, are divided into those that produce seeds in cones and those that produce seeds in the ovaries of flowers. Se...
train
sciq
null
What process takes place when echinoderms release their gametes into the water?
[ "migration", "fertilization", "stimulation", "isolation" ]
B
The echinoderm nervous system has a nerve ring at the center and five radial nerves extending outward along the arms. There is no centralized nervous control. Echinoderms have separate sexes and release their gametes into the water where fertilization takes place. Echinoderms may also reproduce asexually through regene...
train
sciq
null
Salt hydrolysis is a reaction in which one of the ions from a salt reacts with what?
[ "fat", "proteins", "air", "water" ]
D
The fluoride ion is acting as a weak Brønsted-Lowry base. The hydroxide ion that is produced as a result of the above reaction makes the solution slightly basic. Salt hydrolysis is a reaction in which one of the ions from a salt reacts with water, forming either an acidic or basic solution.
train
sciq
null
Do motile cilia usually occur in small or large numbers on the cell surface?
[ "large", "neither", "mixed", "small" ]
A
train
sciq
null
Potassium is a soft, silvery metal that ignites explosively in what?
[ "acid", "air", "cold", "water" ]
D
Potassium is a soft, silvery metal that ignites explosively in water. It easily loses its one valence electron to form positive potassium ions (K + ), which are needed by all living cells. Potassium is so important for plants that it is found in almost all fertilizers, like the one shown here. Potassium is abundant in ...
train
sciq
null
When a solid substance is involved in a chemical reaction, only the matter from which part of the solid is exposed to other reactants?
[ "the surface", "the base", "the top", "the interior" ]
A
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. For example, crushing a ...
train
sciq
null
Which word describes how an extracellular solution can change the volume of a cell by affecting osmosis?
[ "tonicity", "velocity", "instability", "trichina" ]
A
Tonicity Tonicity describes how an extracellular solution can change the volume of a cell by affecting osmosis. A solution's tonicity often directly correlates with the osmolarity of the solution. Osmolarity describes the total solute concentration of the solution. A solution with low osmolarity has a greater number of...
train
sciq
null
The process where eroded material is dropped somewhere is called?
[ "diffusion", "deposition", "maturation", "diffusion" ]
B
Erosion and deposition are responsible for many landforms. Erosion is the transport of sediments. Agents of erosion include flowing water, waves, wind, ice, or gravity. Eroded material is eventually dropped somewhere else. This is called deposition .
train
sciq
null
What was the first amino acid to be isolated?
[ "histamine", "glutathione", "asparagine", "histon" ]
C
The first amino acid to be isolated was asparagine in 1806. It was obtained from protein found in asparagus juice (hence the name). Glycine, the major amino acid found in gelatin, was named for its sweet taste (Greek glykys, meaning “sweet”). In some cases an amino acid found in a protein is actually a derivative of on...
train
sciq
null
Where is the food stored before being mixed with the chyme?
[ "hemispherical of the stomach", "top of the stomach", "fundus of the stomach", "histopathology of the stomach" ]
C
Chemical Digestion The fundus plays an important role, because it stores both undigested food and gases that are released during the process of chemical digestion. Food may sit in the fundus of the stomach for a while before being mixed with the chyme. While the food is in the fundus, the digestive activities of saliva...
train
sciq
null
What kind of biome or climate might you find very close to the earth's poles, as well as up on high mountains?
[ "taiga", "tropical", "tundra", "desert" ]
C
Tundra is found near the poles and up on high mountains.
train
sciq
null
What type of waves travel through the body of a planet?
[ "vacuum waves", "energy waves", "body waves", "gas waves" ]
C
Body waves travel through the body of a planet. Surface waves travel along the surface.
train
sciq
null
What type of energy occurs by splitting the nuclei of radioactive uranium?
[ "kinetic", "atomic", "nuclear", "microwave" ]
C
Nuclear energy is produced by splitting the nuclei of radioactive uranium. This doesn’t release air pollution or carbon dioxide, but it does produce dangerous radioactive wastes.
train
sciq
null
Like skeletal muscle, cardiac muscle is what?
[ "atrophied", "tissue", "cylindrical", "striated" ]
D
train
sciq
null
Rising and falling levels of what will result in progression of the ovarian and menstrual cycles?
[ "oxygen", "red blood cells", "blood pressure", "hormones" ]
D
Figure 43.17 Rising and falling hormone levels result in progression of the ovarian and menstrual cycles. (credit: modification of work by Mikael Häggström).
train
sciq
null
What is the term for how much matter is packed into a given space?
[ "mass", "density", "volume", "opacity" ]
B
Density is a quantity that expresses how much matter is packed into a given space. The amount of matter is its mass, and the space it takes up is its volume. To calculate the density of an object, then, you would use this formula:.
train
sciq
null
Phototrophic organisms capture light energy from the sun and convert it into what type of energy inside their cells?
[ "mechanical energy", "radiation energy", "chemical energy", "solar power" ]
C
Phototrophic organisms capture light energy from the sun and convert it into chemical energy inside their cells.
train
sciq
null
What is an animal that picks up pollen on its body and carries it to another flower called?
[ "fungi", "lizard", "pollinator", "rodent" ]
C
The showy petals of flowers evolved to help attract pollinators. Wind-blown pollen might land just anywhere and be wasted. A pollinator is an animal that picks up pollen on its body and carries it directly to another flower of the same species. This helps ensure that pollination occurs. Pollinators are usually small an...
train
sciq
null
How many bones make up an adult human skeleton?
[ "130", "206", "186", "244" ]
B
The adult human skeleton includes 206 bones and other tissues. It supports the body, protects internal organs, produces blood cells, and maintains mineral homeostasis.
train
sciq
null
The process in which a sperm unites with an egg is called?
[ "infection", "migration", "fertilization", "absorption" ]
C
This image depicts a true wonder of nature. This tiny human sperm is penetrating a much larger egg. These two cells will unite to become a brand new human being. The process in which they unite is called fertilization.
train
sciq
null
What is the term for the height of the wave?
[ "amplitude", "vibration", "magnitude", "frequency" ]
A
(A) A wave consists of alternation crests and troughs. The wavelength (λ) is defined as the distance between any two consecutive identical points on the waveform. The amplitude is the height of the wave. (B) A wave with a short wavelength (top) has a high frequency because more waves pass a given point in a certain amo...
train
sciq
null
When a plant has what deficiency, guard cells may lose turgor and close stomata?
[ "air", "light", "cold", "water" ]
D
train
sciq
null
What is a combination of two or more substances in any proportions called?
[ "structure", "mix", "mixture", "Combination" ]
C
A mixture is a combination of two or more substances in any proportions. The substances in a mixture do not combine chemically, so they retain their physical properties.
train
sciq
null
What does subduction of a plate lead to?
[ "pressure and volcanism", "swell and volcanism", "melting and volcanism", "bending and volcanism" ]
C
Subduction of a plate leads to melting and volcanism.
train
sciq
null
The mixture of gases that surrounds the planet and makes up the atmosphere is known as ________.
[ "energy", "air", "fuel", "vaccum" ]
B
The atmosphere is a mixture of gases that surrounds the planet. We also call it air. The gases in the atmosphere include nitrogen, oxygen, and carbon dioxide. Along with water vapor, the atmosphere allows life to survive. Without it, Earth would be a harsh, barren world.
train
sciq
null
What system protects the soft organs of the body?
[ "skeletal system", "nervous system", "digestive system", "Cardiovascular system" ]
A
The skeletal system protects the soft organs of the body. For example, the skull surrounds and protects the brain. The ribs protect the heart and lungs.
train
sciq
null
Before the atmosphere became oxygenated, the planet was subjected to what harmful energy source, meaning the first organisms would have flourished where they were more protected?
[ "radiation", "conduction", "convection", "evaporation" ]
A
Before the atmosphere became oxygenated, the planet was subjected to strong radiation; thus, the first organisms would have flourished where they were more protected, such as in ocean depths or beneath the surface of Earth. At this time, too, strong volcanic activity was common on Earth, so it is likely that these firs...
train
sciq
null
Turbulent sounds, at the onset of blood flow when the cuff pressure becomes sufficiently small are called?
[ "pinworm sounds", "choanocyte sounds", "korotkoff sounds", "whooping sounds" ]
C
12.5 The Onset of Turbulence Sometimes we can predict if flow will be laminar or turbulent. We know that flow in a very smooth tube or around a smooth, streamlined object will be laminar at low velocity. We also know that at high velocity, even flow in a smooth tube or around a smooth object will experience turbulence....
train
sciq
null
What is the simple sugar that living things us to store energy?
[ "brown", "glucose", "chloride", "nicotine" ]
B
simple sugar that all living things use to store and transport energy.
train
sciq
null
Reversing the orientation of a chromosomal segment is called what?
[ "inversions", "occurrences", "spontaneous mutation", "volatiles" ]
A
Inversions are reversing the orientation of a chromosomal segment.
train
sciq
null
What does the clitellum secrete, while the sperm received are stored temporarily?
[ "pathogen of mucus", "discharge of mucus", "cocoon of mucus", "amoeba of mucus" ]
C
train
sciq
null
What forms when water vapor condenses around particles in the air?
[ "wind", "clouds", "storms", "humididty" ]
B
Clouds form when water vapor condenses around particles in the air. The particles are specks of matter, such as dust or smoke. Billions of these tiny water droplets come together to make up a cloud. If the air is very cold, ice crystals form instead of liquid water.
train
sciq
null
The cycle of copper reacting is a good example of what principle?
[ "conservation of momentum", "conservation of energy", "law of inertia", "conservation of mass" ]
D
A series of chemical reactions where an initial amount of copper reacts with nitric acid, goes into solution, and disappears. Then a series of reactions proceed, only to have the copper metal recovered. The copper cycle is a good illustration of how mass is conserved in a given chemical reaction.
train
sciq
null
A ramp is an example of what?
[ "level plane", "change plane", "move plane", "inclined plane" ]
D
A ramp like the one in the Figure below is another example of an inclined plane. Inclined planes make it easier to move objects to a higher elevation. The sloping surface of the inclined plane supports part of the weight of the object as it moves up the slope. As a result, it takes less force to move the object uphill....
train
sciq
null
What kind of muscle is responsible for hollow organs contracting?
[ "micro muscle", "rough muscle", "tough muscle", "smooth muscle" ]
D
Smooth muscles and cardiac muscles are not attached to bone. Recall that these types of muscles are under involuntary control. Smooth muscle is responsible for the contractility of hollow organs, such as blood vessels, the gastrointestinal tract, the bladder, or the uterus. Like skeletal muscles, smooth muscle fibers d...
train
sciq
null
In vascular plants, do primary roots grow downward or to the side?
[ "neither", "it depends", "to the side", "downward" ]
D
Roots are important organs in all vascular plants. Most vascular plants have two types of roots: primary roots that grow downward and secondary roots that branch out to the side. Together, all the roots of a plant make up a root system .
train
sciq
null
What type of light has shorter wavelengths than visible light and has enough energy to kill bacteria?
[ "ultraviolet", "luminescence", "infrared", "reflected light" ]
A
Mid-wavelength electromagnetic waves are called light. Light consists of visible, infrared, and ultraviolet light. Humans can see only visible light. Infrared light has longer wavelengths than visible light and is perceived as warmth. Ultraviolet light has shorter wavelengths than visible light and has enough energy to...
train
sciq
null
What characteristic of the endothelium structure minimizes resistance to the flow of blood?
[ "smooth surface", "transition surface", "uneven surface", "liquid surface" ]
A
train
sciq
null
What type of bonds contain atoms that possess either a partial positive or a partial negative charge?
[ "hot bonds", "polar bonds", "ionic bonds", "geologic bonds" ]
B
Polar bonds contain atoms that possess either a partial positive or a partial negative charge.
train
sciq
null
The body contains how many types of muscle tissue?
[ "two", "four", "seven", "three" ]
D
38.4 Muscle Contraction and Locomotion The body contains three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle. Skeleton muscle tissue is composed of sarcomeres, the functional units of muscle tissue. Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past ea...
train
sciq
null
The eyes of all vertebrates possess a single one of these structures?
[ "sty", "vessel", "lens", "stalk" ]
C
train
sciq
null
The final stage of labor is delivery of the what?
[ "placenta", "uterus", "umbilical cord", "embryo" ]
A
train
sciq
null
All proteins are made of monomers called what?
[ "aminotides", "peptides", "monotides", "amino acids" ]
D
Proteins are molecules that have many different functions in living things. All proteins are made of monomers called amino acids ( Figure below ) that connect together like beads on a necklace ( Figure below ). There are only 20 common amino acids needed to build proteins. These amino acids form in thousands of differe...
train
sciq
null
What system consists of all the muscles of the body?
[ "vascular", "endocrine", "digestive", "muscular" ]
D
The muscular system consists of all the muscles of the body. Does the word muscle make you think of the bulging biceps of a weightlifter, like the man in Figure below ? Muscles such as biceps that move the body are easy to feel and see, but they aren’t the only muscles in the human body. Many muscles are deep within th...
train
sciq
null
Photoautotrophs and chemoautotrophs are two basic types of what?
[ "plants", "consumers", "decomposers", "autotrophs" ]
D
Producers are organisms that produce food for themselves and other organisms. They use energy and simple inorganic molecules to make organic compounds. The stability of producers is vital to ecosystems because all organisms need organic molecules. Producers are also called autotrophs . There are two basic types of auto...
train
sciq
null
Many genetic disorders are caused by mutations in one or a few of?
[ "blood cells", "genes", "lesions", "organs" ]
B
Many genetic disorders are caused by mutations in one or a few genes.
train
sciq
null
In some cases, the nervous system directly stimulates endocrine glands to release hormones, which is referred to as what?
[ "neural stimuli", "brain stimuli", "functional stimuli", "active stimuli" ]
A
Neural Stimuli In some cases, the nervous system directly stimulates endocrine glands to release hormones, which is referred to as neural stimuli. Recall that in a short-term stress response, the hormones epinephrine and norepinephrine are important for.
train
sciq
null
What kind of reproduction results in offspring that are generally all genetically different?
[ "perceptual", "asexual", "individual", "sexual" ]
D
Sexual reproduction is typically slower. However, it also has an advantage. Sexual reproduction results in offspring that are all genetically different. This can be a big plus for a species. The variation may help it adapt to changes in the environment.
train
sciq
null
When traveling through space what do mechanical waves lose?
[ "Speed", "Force", "Mass", "energy" ]
D
An electromagnetic wave is a transverse wave that can travel across space as well as through matter. When it travels through space, it doesn’t lose energy to a medium as a mechanical wave does.
train
sciq
null
How many types of major tissues do modern plants have?
[ "four", "three", "two", "seven" ]
B
A tissue is a group of specialized cells of the same kind that perform the same function. Modern plants have three major types of tissues. They're called dermal, ground, and vascular tissues.
train
sciq
null
How does a reduced sweating ability affect elderly people?
[ "less energy", "extreme heat intolerance", "loss of mental ability", "extreme tiredness" ]
B
The accessory structures also have lowered activity, generating thinner hair and nails, and reduced amounts of sebum and sweat. A reduced sweating ability can cause some elderly to be intolerant to extreme heat. Other cells in the skin, such as melanocytes and dendritic cells, also become less active, leading to a pale...
train
sciq
null
What substance do developing seeds produce which promotes fruit growth?
[ "auxin", "pepsin", "interferon", "xenon" ]
A
train
sciq
null
Different clouds are associated with different types of what?
[ "magnetic fields", "weather conditions", "zodiac signs", "biomes" ]
B
train
sciq
null
The testes produce sperm and secrete what?
[ "testosterone", "melanin", "thyroxine", "estrogen" ]
A
The testes produce sperm and secrete testosterone.
train
sciq
null
Friction does negative work and removes some of the energy the person expends and converts it to which kind of energy?
[ "evaporation", "thermal", "erosion", "hydro" ]
B
Discussion for (a) This value is the net work done on the package. The person actually does more work than this, because friction opposes the motion. Friction does negative work and removes some of the energy the person expends and converts it to thermal energy. The net work equals the sum of the work done by each indi...
train
sciq
null
What happens when forces of evolution work over a long period of time?
[ "developmental evolution", "macroevolution", "Microevolution", "substantial evolution" ]
B
What happens when forces of evolution work over a long period of time? The answer is macroevolution. An example is the evolution of a new species.
train
sciq
null
What measurement is used to describe the amount of water vapor in the air?
[ "precipitation", "heat", "barometric pressure", "humidity" ]
D
Humidity is the amount of water vapor in the air. Relative humidity is the percent of water vapor in the air relative to the total amount the air can hold. The total amount depends on temperature.
train
sciq
null
Sebaceous glands produce an oily substance called what?
[ "pus", "ear wax", "sebum", "synovial fluid" ]
C
Sebaceous glands produce an oily substance called sebum . Sebum is secreted into hair follicles and makes its way to the skin surface. It waterproofs the hair and skin and helps prevent them from drying out. Sebum also has antibacterial properties, so it inhibits the growth of microorganisms on the skin.
train
sciq
null
In what kind of a series does the genetic code work?
[ "three-letter codes", "nine letter-codes", "four-letter codes", "universal codes" ]
A
The genetic code works as a series of three-letter codes. Each sequence of three letters, called a triplet, corresponds to one of the twenty common amino acids. The triplets are read by the cell, one after the other, in the process of protein synthesis. The Table below shows all of the possible triplets and the amino a...
train
sciq
null
Free-flowing electrons enable what materials to conduct electricity and heat very well?
[ "acids", "noble gases", "alloys", "metals" ]
D
This model for metallic bonding explains some of the physical properties of metals. Metals conduct electricity and heat very well because of their free-flowing electrons. As electrons enter one end of a piece of metal, an equal number of electrons flow outward from the other end, allowing an electrical current to pass ...
train
sciq
null
What is the difference in voltage across a resistor or other electrical devices called?
[ "volt effect", "falling voltage", "power drop", "voltage drop" ]
D
The name electric current is the name given to the phenomenon that occurs when an electric field moves down a wire at close to the speed of light. Voltage is the electrical energy density that causes the electric current. Resistance is the amount a device in the wire resists the flow of current by converting electrical...
train
sciq
null
What is the science that describes the ancestral and descendant connections between organisms?
[ "phylogeny", "organic science", "polygamy", "experimentally" ]
A
Building Phylogenetic Trees with Analysis of DNA Sequence Alignments All living organisms display patterns of relationships derived from their evolutionary history. Phylogeny is the science that describes the relative connections between organisms, in terms of ancestral and descendant species. Phylogenetic trees, such ...
train
sciq
null
According to collision theory, particles that lack what kind of energy may collide, but the particles will simply bounce off one another unchanged?
[ "elastic energy", "kinetic energy", "viscosity energy", "residual energy" ]
B
The behavior of the atoms, molecules, or ions that comprise the reactants is responsible for the rates of a given chemical reaction. Collision theory is a set of principles that states that the reacting particles can form products when they collide with one another provided those collisions have enough kinetic energy a...
train
sciq
null
Muscles that move what long bone originate on the pelvic girdle?
[ "sacrum", "femur", "tibia", "patella" ]
B
Gluteal Region Muscles That Move the Femur Most muscles that insert on the femur (the thigh bone) and move it, originate on the pelvic girdle. The psoas major and iliacus make up the iliopsoas group. Some of the largest and most powerful muscles in the body are the gluteal muscles or gluteal group. The gluteus maximus ...
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In an atom, what is determined by electron distribution in shells?
[ "chemical behavior", "electromagnetism", "ionic bonds", "covalence" ]
A
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What term is defined as a way of writing very large or small numbers that uses exponents?
[ "quadratic notation", "exponential notation", "certain notation", "scientific notation" ]
D
Quantities in science may be very large or very small. This usually requires many zeroes to the left or right of the decimal point. Such numbers can be hard to read and write accurately. That’s where scientific notation comes in. Scientific notation is a way of writing very large or small numbers that uses exponents. N...
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Electrons are always added to which energy level first?
[ "the major", "the lowest", "the highest", "the second" ]
B
Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible, and then electrons are added to the next higher energy level until that level is full, and so on. The maximum number of electrons at a given energy level depends on its number of orbitals. There are at mos...
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What type of symmetry do echinoderms show?
[ "radial", "mirrored", "lateral", "parallel" ]
A
As mentioned earlier, echinoderms show radial symmetry. Other key echinoderm features include an internal skeleton and spines, as well as a few organs and organ systems. Although echinoderms look like they have a hard exterior, they do not have an external skeleton. Instead, a thin outer skin covers an internal skeleto...
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Nails cover the tips of what?
[ "lips and teeth", "fingers and lips", "fingers and toes", "ribs and nerves" ]
C
Nails are similar to claws in other animals. They cover the tips of fingers and toes. Fingernails and toenails both grow from nail beds. As the nail grows, more cells are added at the nail bed. Older cells get pushed away from the nail bed and the nail grows longer. There are no nerve endings in the nail. Otherwise cut...
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Which carrier molecule becomes less effective at binding oxygen as temperature increases?
[ "hydrogen", "helium", "water", "hemoglobin" ]
D
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What is found at the top of the stamen?
[ "pistil", "fungi", "petals", "pollen" ]
D
The next structure is the stamen , consisting of the stalk-like filament that holds up the anther , or pollen sac. The pollen, which is found at the top of the stamen, is the male gametophyte.
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What field of study is called the language of science?
[ "physics", "linguistics", "mathematics", "logic" ]
C
The field of science has gotten so big that it is common to separate it into more specific fields. First, there is mathematics, the language of science. All scientific fields use mathematics to express themselves—some more than others. Physics and astronomy are scientific fields concerned with the fundamental interacti...
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What is the term for tough, flexible connective tissue that contains the protein collagen?
[ "cartilage", "cuticle", "membrane", "muscle" ]
A
Cartilage is a tough, flexible connective tissue that contains the protein collagen. It covers the ends of bones where they meet. The gray tissue in Figure below is cartilage.
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Liquid water changing to water vapor is called?
[ "transpiration", "oxidation", "evaporation", "respiration" ]
C
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What is used to prevent some infectious diseases?
[ "vaccines", "pesticides", "pathogens", "radiation" ]
A
Vaccines are available for some infectious diseases. For example, there are vaccines to prevent measles, mumps, whooping cough, and chicken pox. These vaccines are recommended for infants and young children.
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The change in the characteristics of living things over time is known as _________
[ "spontaneous mutation", "evolution", "generation", "variation" ]
B
Evolution is a change in the characteristics of living things over time. Evolution occurs by a process called natural selection. In natural selection, some living things produce more offspring than others, so they pass more genes to the next generation than others do. Over many generations, this can lead to major chang...
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What provides building materials for the body?
[ "water", "food", "heat", "energy" ]
B
Food provides building materials for the body. The body needs building materials for growth and repair.
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What is the term for animals that eat producers to get energy?
[ "secondary consumers", "herbivores", "carnivores", "predators" ]
B
Herbivores are animals that eat producers to get energy. For example, rabbits and deer are herbivores that eat plants. The caterpillar pictured below ( Figure below ) is a herbivore. Animals that eat phytoplankton in aquatic environments are also herbivores.
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Farsightedness, or hyperopia, is the condition in which distant objects are seen clearly, but nearby objects are?
[ "darker", "inverted", "invisible", "blurry" ]
D
Farsightedness, or hyperopia, is the condition in which distant objects are seen clearly, but nearby objects are blurry. It occurs when the eyeball is shorter than normal. This causes images to be focused in back of the retina. Hyperopia can be corrected with convex lenses. The lenses focus images farther forward in th...
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