Deck 33: A Range of Biology

Question 1

Why is the phospholipid bilayer important to cell survival? Select the TWO answers that are correct.

A) It acts as a barrier for some,but not all,molecules on either side of it.
B) It maintains homeostasis by forming an insulating layer around the cell.
C) It anchors nucleotides together as they form molecules of DNA.
D) It blocks small,nonpolar molecules from entering the cell and harming it.
E) It separates the cellular environment from the external environment.

Answer 1

A,E

Question 2

Which statement describes a hydrogen bond between two water molecules?

A) a weak bond in which the oxygen atom of one molecule takes an electron away from the hydrogen atom of another water molecule
B) a weak bond between the slightly negative oxygen atom of one water molecule and the slightly positive hydrogen atoms of another water molecule
C) a weak bond between the slightly positive oxygen atom of one water molecule and the slightly negative hydrogen atoms of another water molecule
D) a weak bond in which the oxygen atom of one molecule stably shares electrons with the hydrogen atom of another water molecule
E) a weak bond in which the oxygen atom of one molecule donates an electron to the hydrogen atom of another water molecule

Answer 2

B

Question 3

Polar bears rely on Arctic ice sheets and icebergs on the surface of water as a part of their habitat.How would the habitat of polar bears be affected if solid water was more dense than liquid water?

A) Ice would sink rather than float,so there would be no ice sheets or ice bergs.
B) Water would be unable to freeze at all,causing the total loss of polar bear habitat.
C) Permanent ice would form on the surface,creating more habitat for polar bears.
D) Water would stay liquid over a wider temperature range,limiting ice formation.
E) Water would become polar,causing it to freeze more solidly and melt less easily.

Answer 3

A

Question 4

One argument explaining why viruses are not living is that viruses depend on the cells of other living creatures in order to multiply.Which characteristics of life does this argument use? Select the TWO answers that are correct.

A) growth
B) homeostasis
C) respond to stimuli
D) reproduction
E) use energy

Question 5

Where are the protons,neutrons,and electrons located in an atom?

A) Protons and neutrons are located in the nucleus,and electrons are located in orbitals.
B) Protons,electrons,and neutrons are located in the nucleus,and energy is located in orbitals.
C) Electrons and neutrons are located in the nucleus,and protons are located in orbitals.
D) Protons and electrons are located in the nucleus,and neutrons are located in orbitals.
E) Electrons and neutrons are located in orbitals,and protons are located in the nucleus.

Question 6

Anna is majoring in public health.She is designing an epidemiological study to examine the relationship between alcohol consumption and academic performance at her university.In addition to ensuring that she has a large enough sample size,what strategy should she take to make sure her conclusions are accurate?

A) give the survey to the students that are most likely to respond because they carry a smaller course load
B) target the surveys to the students that are involved in the designated driver campaign on campus
C) randomly survey a group of participants that are representative of the general student body
D) give the surveys out to members of the student groups known for throwing the wildest parties on campus
E) hand out the survey only to friends and to fellow students enrolled in public health classes

Question 7

What characteristics does a scientific hypothesis have? Select the TWO answers that are correct.

A) The hypothesis is something that can be tested.
B) The hypothesis contains a supernatural element.
C) The hypothesis could be proven false.
D) The hypothesis is based on an opinion.
E) The hypothesis has already been proven correct.

Question 8

Which trait is NOT a functional characteristic of all living things?

A) sense and respond to stimuli
B) protect self from predators
C) grow and reproduce
D) maintain homeostasis
E) acquire and consume energy

Question 9

What determines the identity of a particular atom? Select the TWO answers that are correct.

A) total number of neutrons in orbitals
B) total number of electrons in orbitals
C) number of protons and number of neutrons in the nucleus
D) number of protons in the outermost energy shell
E) number of electrons in the inner most energy shell

Question 10

Which example describes the set-up of a controlled experiment?

A) Ten subjects receive a new drug and another ten subjects receive a sugar pill.
B) Twenty subjects with knee pain receive the same treatment to relieve joint pain.
C) A doctor treats one subject for a disease and observes how quickly the patient recovers.
D) Researchers collect lifestyle data from fifty questionnaires submitted by subjects with the same disease.
E) Fifteen subjects with the common cold take a cold medicine and answer questions about its effects.

Question 11

What makes ice less dense than liquid water?

A) Covalent bonds within water molecules expand when solid.
B) Hydrogen donates electrons to oxygen as freezing occurs.
C) Nuclear forces form expansive crystals as freezing occurs.
D) Ionic bonds between water molecules expand when solid.
E) Hydrogen bonds between water molecules expand when solid.

Question 12

What characteristics make a particular molecule organic? Select the TWO answers that are correct.

A) a carbon-oxygen bond
B) presence of carbon
C) a carbon backbone
D) a carbon-nitrogen bond
E) a carbon-hydrogen bond

Question 13

Using the same independent and dependent variables as in the first experiment,researchers could extend the studies to test which of the following hypotheses? Select the TWO answers that are correct.

A) Caffeine improves memory function in elderly people when consumed at least two hours before testing.
B) Caffeine does not improve memory function in women aged 20 to 40.
C) The risk of developing cancer in advanced age increases with caffeine consumption.
D) Antioxidant-rich foods improve memory function in men and women over the age of 65.
E) Young adults between the ages of 18 and 25 are less likely to drink coffee than elderly adults.

Question 14

What did the researchers conclude about how caffeine consumption affects memory function from the experiment?

A) Caffeine improves memory function in elderly people.
B) Decaffeinated coffee worsens memory function in elderly people.
C) Caffeine has no effect on memory function in elderly people.
D) Elderly people should drink coffee in the afternoon to boost memory function.
E) Elderly people have poorer memory function in the afternoon as compared to young adults.

Question 15

Why is sample size important?

A) Statistical significance is best achieved with a small sample size.
B) Larger sample size increases the likelihood that the results of a study are not due to random chance.
C) Relationships between variables can be determined only using a large sample size.
D) Researchers will always draw the right conclusions about a set of data if the sample size is large enough.
E) Legitimate scientific studies can be performed using only a large sample size.

Question 16

Why is the phospholipid bilayer considered semipermeable?

A) Large molecules can only pass through the layer of hydrophilic phospholipids.
B) The bilayer is a barrier to some,but not all,substances on either side of it.
C) The hydrophobic tails act as a barrier to nonpolar molecules.
D) The bilayer is completely nonpolar,which prevents some molecules from passing.
E) Small,nonpolar molecules do not pass through the phospholipid bilayer.

Question 17

Which statements describe the relationship between correlation and causation? Select the TWO answers that are correct.

A) Correlation alone is not sufficient evidence to attribute causation.
B) Strong correlations among variables are evidence of causation by the independent variable.
C) Either variable might be the cause,or both variables might be influenced by a third unknown variable.
D) When two variables correlate,it strongly implies that a third unknown variable is the causal factor.
E) When a correlation has a high probability,it strongly implies causation.

Question 18

How does the molecular structure of a water molecule affect its polarity?

A) The oxygen has a partial positive charge and the hydrogens have a partial negative charge,yielding a weakly polar water molecule that can form hydrogen bonds.
B) The oxygen has a partial negative charge and the hydrogens have a partial positive charge,yielding a weakly polar water molecule that can form hydrogen bonds.
C) The oxygen and hydrogen rapidly exchange electrons in their outermost energy shells,producing structures that can form hydrogen bonds.
D) The oxygen takes an electron from each hydrogen,yielding a negatively charged oxygen and two positively charged hydrogens that can form hydrogen bonds.
E) The oxygen donates an electron to each hydrogen,yielding a positively charged oxygen and two negatively charged hydrogens that can form hydrogen bonds.

Question 19

Which part of an atom forms covalent bonds with other atoms?

A) protons in the outermost energy shell
B) electrons in the innermost energy shell
C) neutrons in the outermost energy shell
D) protons in the innermost energy shell
E) electrons in the outermost energy shell

Question 20

Which statement describes a correlation between two variables?

A) Correlated variables strongly imply their change is caused by a third,perhaps unknown,variable.
B) Correlated variables are dependent;how they change is predicted by change in a third unknown variable.
C) Correlated variables are interdependent;as one varies so does the other in a predictable fashion.
D) Correlated variables are independent;how one varies does not have an effect on how the other varies.
E) Correlated variables demonstrate causality;change in the independent variable directs change in the dependent variable.

Question 21

Why are eukaryotic cells unaffected by streptomycin and similar antibiotics?

A) Eukaryotic cells are unaffected by these antibiotics because eukaryotic cells lack cell walls.
B) Eukaryotic cell walls are unaffected by these antibiotics because the cell walls do not contain peptidoglycan.
C) Eukaryotic DNA replication is not disrupted because these antibiotics do not disrupt the enzymes used to produce eukaryotic DNA.
D) Eukaryotic protein synthesis is not disrupted because these antibiotics do not disrupt eukaryotic ribosomal activity.
E) Eukaryotic cells have organelles called lysosomes that engulf and break down these types of antibiotics.

Question 22

How does water dissolve table salt?

A) Water is a polar molecule that disrupts hydrogen bonds between sodium and chloride.
B) Water is a nonpolar molecule that dissolves covalent bonds between sodium and chloride.
C) Water is a polar molecule that disrupts ionic bonds between sodium and chloride.
D) Water is a polar molecule that takes electrons from sodium chloride.
E) Water is a nonpolar molecule that breaks the ionic bonds between sodium and chloride.

Question 23

How do RNA and DNA molecules differ? Select the TWO answers that are correct.

A) RNA is single-stranded,whereas DNA is double-stranded.
B) Uracil is used in RNA,whereas thymine is used in DNA.
C) RNA has one fatty acid chain,whereas DNA has two of them.
D) Adenine is used in RNA,whereas cytosine is used in DNA.
E) RNA contains sugars in its backbone,whereas DNA does not.

Question 24

Which statements describe the structure of the cell membrane? Select the TWO answers that are correct.

A) The cell membrane is composed of a bilayer of phosphoproteins,each of which contains a hydrophilic head and a hydrophobic tail.
B) The hydrophilic head interacts with the external environment or the cytoplasm,and the hydrophobic tail interacts with other phospholipid tails within the cell membrane.
C) The hydrophilic head interacts with proteins embedded in the membrane,and the hydrophobic tail interacts with the external environment or the cytoplasm.
D) The cell membrane is composed of a single layer of phospholipids,each of which contains a hydrophilic head and a hydrophobic tail.
E) The cell membrane is composed of a bilayer of phospholipids,each of which contains a hydrophilic head and a hydrophobic tail.

Question 25

Which substances have an alkaline pH? Select the TWO answers that are correct.

A) coffee
B) battery acid
C) orange juice
D) drain cleaner
E) baking soda

Question 26

Which tasks do water vacuoles and cell walls both perform in plant cells? Select the TWO answers that are correct.

A) keep plant upright
B) maintain cell shape
C) protect from bacteria
D) magnify visible light
E) absorb UV light

Question 27

How do triglycerides and phospholipids differ? Select the TWO answers that are correct.

A) Phospholipids have two fatty acid tails,whereas triglycerides have three.
B) Phospholipids store energy,whereas triglycerides are cell membrane components.
C) Phospholipids are saturated with hydrogens,whereas triglycerides are unsaturated.
D) Phospholipids have a hydrophilic phosphate group in place of one fatty acid tail.
E) Phospholipids have ribose in place of the deoxyribose used in triglycerides.

Question 28

How does the cell wall protect prokaryotic cells in a hypotonic solution?

A) Because cells shrivel in a hypotonic environment,the bacterial cell wall counteracts the inward osmotic pressure and prevents the cell from being crushed.
B) Because cells swell in a hypotonic environment,the bacterial cell wall counteracts the inward osmotic pressure and prevents the cell from being crushed.
C) Because cells shrivel in a hypotonic environment,the bacterial cell wall counteracts the outward osmotic pressure and prevents the cell from bursting.
D) Because cells are osmotically balanced in a hypotonic environment,the cell wall allows water flow back and forth,continuing to maintain the osmotic balance.
E) Because cells swell in a hypotonic environment,the bacterial cell wall counteracts the outward osmotic pressure and prevents the cell from bursting.

Question 29

What functions do membrane proteins serve?

A) synthesize phospholipids for the maintenance and growth of the cell membrane
B) transport nutrients into the cell that cannot otherwise cross the phospholipid bilayer
C) transport wastes out of the cell that cannot otherwise cross the cell membrane
D) prevent small,uncharged substances from crossing the phospholipid bilayer
E) synthesize DNA within the cell using raw materials found outside the cell

Question 30

How are eukaryotic cells different from prokaryotic cells? Select the TWO answers that are correct.

A) Eukaryotic cells have organelles,whereas prokaryotic cells do not.
B) Prokaryotic cells are generally smaller than eukaryotic cells.
C) Prokaryotic cells have a nucleus,whereas eukaryotic cells do not.
D) Eukaryotic cells have ribosomes,whereas prokaryotic cells do not.
E) Prokaryotic cells use RNA,whereas eukaryotic cells use DNA.

Question 31

Why are nucleic acids considered macromolecules but not macronutrients?

A) They can be assembled into large molecules,but organisms need only small quantities of them in the diet.
B) They can be assembled into DNA or RNA,but organisms cannot break them down into their constituent parts.
C) They can be assembled into large molecules,but they do not serve as an energy source.
D) They can be assembled into large proteins,but organisms require only small amounts of them in the diet.
E) They can be assembled into DNA or RNA,but they are smaller than amino acids,carbohydrates,or lipids.

Question 32

How do streptomycin and similar antibiotics affect prokaryotic cells?

A) These antibiotics interfere with cell wall formation.
B) These antibiotics interfere with protein synthesis.
C) These antibiotics interfere with peptidoglycan formation.
D) These antibiotics interfere with cell membrane integrity.
E) These antibiotics interfere with DNA replication.

Question 33

How do penicillin and similar antibiotics affect prokaryotic cells?

A) These antibiotics interfere with the action of prokaryotic ribosomes which disrupts proper cell membrane formation,resulting in cell death.
B) These antibiotics disrupt the formation of the cell wall so it cannot counteract osmotic pressure in a hypotonic environment,resulting in cell lysis.
C) These antibiotics disrupt the formation of the cell wall so it cannot counteract osmotic pressure in a hypertonic environment,resulting in cell lysis.
D) These antibiotics disrupt the formation of the cell membrane so it cannot counteract osmotic pressure in a hypotonic environment,resulting in cell lysis.
E) These antibiotics interfere with the action of prokaryotic ribosomes so normal protein synthesis cannot occur,resulting in cell death.

Question 34

Why are chloroplasts essential to the survival of many animals as well as plants?

A) Photosynthesis generates protein building blocks essential to animal functioning that cannot be acquired by animals in any other way.
B) Animals do not have chloroplasts and must depend on organisms that can photosynthesize the energy they need.
C) Chloroplasts allow both animals and plants to break down organic molecules and use the energy stored in the molecules.
D) Many animals can only produce their own energy after they have consumed sufficient photosynthetic chloroplasts.
E) Chloroplasts are rich in fats and lipids that are generated by photosynthesis satisfying the energy requirements of many animals.

Question 35

Why do salt crystals form in a pan of seawater from which the water has been evaporated?

A) In the absence of water,sodium and chloride form ionic bonds and aggregate into crystals.
B) In the absence of water,chloride donates electrons to sodium and the compounds aggregate into crystals.
C) In the absence of water,sodium and chloride share electrons in a stable bond that permits crystal formation.
D) In the absence of water,sodium and chloride form hydrogen bonds and aggregate into crystals.
E) In the absence of water,sodium and chloride form covalent bonds and aggregate into crystals.

Question 36

What is the relationship between acids,bases,and hydroxide ions?

A) Acids contain excess hydroxide ions,whereas bases contain relatively few hydroxide ions.
B) Acids strengthen and bases weaken as hydroxide concentration increases.
C) Acids contain only hydroxide ions,whereas bases contain no hydroxide ions.
D) Acids contain relatively few hydroxide ions,whereas bases contain excess hydroxide ions.
E) Acids contain no hydroxide ions,whereas bases contain only hydroxide ions.

Question 37

What must happen to macromolecules before they can be absorbed by the body?

A) They must be assembled into chains with coenzymes.
B) They must be chemically modified with cofactors.
C) They must be digested into their constituent subunits.
D) They must be transformed into essential nutrients.
E) They must be free of all covalent chemical bonds.

Question 38

Which statements describe catabolic and anabolic reactions? Select the TWO answers that are correct.

A) Catabolic reactions remove chemical bonds and result in larger substances being broken down into smaller ones.
B) Catabolic reactions add chemical bonds and result in the formation of tissues and the enzymes used in digestion.
C) Catabolic reactions add chemical bonds and result in smaller molecules being built up into larger ones.
D) Anabolic reactions remove chemical bonds and result in larger substances being broken down into smaller ones.
E) Anabolic reactions add chemical bonds and result in smaller molecules being built up into larger ones.

Question 39

How does the shape of an enzyme affect its function? Select the TWO answers that are correct.

A) An enzyme must maintain a constantly rigid shape to properly function.
B) Enzyme shape determines what substrate the active site can bind.
C) When an enzyme binds a substrate,the enzyme's shape changes to facilitate a chemical reaction.
D) A misshapen enzyme typically improves the efficiency of a chemical reaction.
E) An enzyme that lacks a proper shape or conformation dissolves in the cytoplasm.

Question 40

How does the DNA of prokaryotic cells differ from the DNA of eukaryotic cells?

A) Prokaryotic DNA is composed of four nucleotides,whereas eukaryotic DNA is composed of five nucleotides.
B) Prokaryotic DNA is bound by an organelle,whereas eukaryotic DNA is free floating in the cytoplasm.
C) Prokaryotic DNA has a linear structure,whereas eukaryotic DNA has a circular,closed-loop structure.
D) Prokaryotic DNA is contained in the cytoplasm,whereas eukaryotic DNA is contained in the nucleus.
E) Prokaryotic DNA is protected by a cell membrane,whereas eukaryotic DNA is protected by a cell wall.

Question 41

How does an enzyme affect the activation energy of a reaction?

A) It raises the energy of activation,which makes the reaction it regulates less likely to occur and decreases the chemical product yield.
B) It lowers the energy of activation,which makes the reaction it catalyzes less likely to occur and slows down the production of the chemical product.
C) It decreases the energy of activation,which results in more energy being needed to initiate the reaction and increases the yield of the chemical product.
D) It increases the energy of activation,which decreases the likelihood of undesirable side reactions and increases the yield of desired products.
E) It reduces the energy of activation,which makes the reaction it facilitates more likely to occur and speeds up the production of the chemical product.

Question 42

What roles do atmospheric gases have in photosynthesis? Select the TWO answers that are correct.

A) Oxygen is produced from water during the light-gathering phase of photosynthesis.
B) Carbon dioxide is from glucose during the light-gathering phase of photosynthesis.
C) Nitrogen is a reactant in photosynthesis that generates chlorophyll molecules.
D) Nitrogen is produced during the synthesis phase of photosynthesis when chlorophyll reacts with water.
E) Carbon dioxide is a reactant for photosynthesis that provides the carbon in glucose.

Question 43

What happens to plants in the absence of light? Select the TWO answers that are correct.

A) Chemical energy is produced using only water and carbon dioxide.
B) Plants stop generating chemical energy from light.
C) Chloroplasts use the energy in glucose to photosynthesize.
D) The process of photosynthesis shuts down.
E) Plants begin converting sugars into fats and proteins.

Question 44

What is the role of pyruvate under anaerobic conditions? Select the TWO answers that are correct.

A) to produce ATP in the citric acid cycle
B) to generate ATP and lactic acid
C) to facilitate fermentation of NAD+
D) to move NADH through electron transport
E) to produce NAD+ from NADH

Question 45

What roles does the circulatory system play in aerobic cellular respiration? Select the TWO answers that are correct.

A) transport oxygen to body tissues and carbon dioxide to the lungs
B) transport glycogen from the liver to body tissues
C) transport glucose from the digestive system to body tissues
D) transport oxygen from the small intestine to the lungs
E) transport ATP from the digestive system to body tissues

Question 46

Why does anaerobic respiration yield less energy than aerobic respiration?

A) Electron transport generates much less ATP under anaerobic conditions.
B) Glycolysis generates only one pyruvate per glucose instead of two.
C) Oxygen cannot donate protons under anaerobic conditions.
D) The citric acid cycle and electron transport are not used in anaerobic respiration.
E) Fermentation uses oxygen less efficiently than electron transport.

Question 47

What bonds in an ATP molecule store the chemical energy used by cells?

A) the bonds between adenine and ribose
B) the bonds between ribose and phosphate
C) the bonds between phosphates
D) the bonds between adenines
E) the bonds between riboses

Question 48

What is activation energy?

A) the energy necessary to bind amino acids into a protein
B) the energy necessary to provide power to an enzyme
C) the energy necessary to turn a product into a reactant
D) the energy necessary to bind a substrate to an enzyme
E) the energy necessary to initiate a chemical reaction

Question 49

Why do leaves appear in shades of yellow,orange,and red in the fall?

A) Cooler fall temperatures change the shape of chlorophyll causing it to absorb different wavelengths of light.
B) The chlorophyll organelles that contain chloroplast pigments breakdown and the leaves reflect more wavelengths of light.
C) In the fall,chloroplasts begin producing enzymes instead of chlorophyll and these reflect different wavelengths of light.
D) Other leaf pigments that were masked by the chlorophyll become visible and reflect wavelengths of light other than green.
E) As the leaves lose chlorophyll,they absorb wavelengths of light that were previously reflected by the pigment.

Question 50

Why do some enzymes need a cofactor in order to function?

A) The presence of a cofactor increases the activation energy of some enzymes.
B) The presence of a cofactor allows some enzymes to bind to their substrates.
C) The presence of a cofactor facilitates the conversion of products into reactants.
D) The presence of a cofactor reduces the activation energy of some enzymes.
E) The presence of a cofactor allows some enzymes to enlarge their active sites.

Question 51

How would an anaerobic environment affect photosynthesis?

A) Photosynthesis would briefly continue using oxygen reserves in mitochondria before stopping.
B) Photosynthesis would continue,assuming there was also sufficient light,water,and carbon dioxide.
C) Photosynthesis would stop because oxygen is needed for carbon dioxide to react with glucose.
D) Photosynthesis would continue because oxygen and carbon dioxide are products and not reactants of photosynthesis.
E) Photosynthesis would stop because oxygen is the key reactant used to generate water from glucose.

Question 52

Under aerobic conditions,when is pyruvate produced and consumed?

A) It is produced in glycolysis and consumed in the citric acid cycle.
B) It is produced in the citric acid cycle and consumed in electron transport.
C) It is produced in electron transport and consumed in glycolysis.
D) It is produced in glycolysis and consumed in fermentation.
E) It is produced in the citric acid cycle and consumed in fermentation.

Question 53

Identify the true statements about wavelengths of light.Select the TWO answers that are correct.

A) Plants absorb wavelengths of light that our eyes perceive as green.
B) Green light has more energy than any other wavelength of visible light.
C) Red light has a longer wavelength and less energy than blue light.
D) Plants reflect wavelengths of light that our eyes cannot detect.
E) In the absence of visible light,photosynthesis proceeds with infrared wavelengths.

Question 54

Which statement best summarizes the law of conservation of energy?

A) Energy is lost when it changes from one form to another.
B) The total energy of a system is constantly decreasing.
C) Energy changes forms and is neither created nor destroyed.
D) Energy is created when it changes from one form to another.
E) Energy should be conserved since it is lost once destroyed.

Question 55

What role does carbon dioxide play in photosynthesis?

A) Carbon dioxide reacts with oxygen to form water and glucose.
B) The oxygen in carbon dioxide is combined with hydrogen to form water.
C) Carbon dioxide reacts with light to form oxygen and glucose.
D) Carbon dioxide is split into hydrogen and oxygen.
E) The carbon in carbon dioxide is incorporated into sugar molecules.

Question 56

Select examples of energy changing forms.Select the THREE answers that are correct.

A) From a high perch,a raptor dives toward its prey.
B) An animal has stores of lipids in its fatty tissues.
C) A green plant absorbs light to make sugar molecules.
D) A seed remains dormant for an extended period.
E) A human jogs down the street for exercise.

Question 57

What stage of aerobic respiration produces the most ATP?

A) citric acid cycle
B) glycolysis
C) electron transport
D) fermentation
E) Krebs cycle

Question 58

Which statements describe cofactors and coenzymes? Select the TWO answers that are correct.

A) Cofactors are made of protein,whereas coenzymes are any other macromolecule.
B) Cofactors and coenzymes both facilitate the binding of enzymes to substrates.
C) Cofactors can be organic or inorganic molecules,whereas coenzymes are only organic.
D) Cofactors and coenzymes both facilitate binding of enzymes to active sites.
E) Cofactors must work with enzymes,whereas coenzymes can work independently.

Question 59

What role does water play in photosynthesis?

A) Water behaves as a pigment in chloroplasts to absorb light.
B) Water acts as an electron acceptor in the formation of glucose.
C) Water reacts with oxygen to convert light energy to chemical energy.
D) Water is a product formed from the reaction of carbon dioxide with glucose.
E) Water provides hydrogen and electrons used in producing glucose.

Question 60

What do plants obtain from soil? Select the TWO answers that are correct.

A) chlorophyll
B) water
C) glucose
D) carbon dioxide
E) nutrients

Question 61

Where is the information for building proteins encoded?

A) amino acids
B) sidechains
C) DNA
D) spidroins
E) beta sheets

Question 62

How do properties of amino acids affect the function of proteins?

A) Amino acids vary in their chemical side chains,and interactions among side chains affect the protein folding that determines protein shape and function.
B) Amino acid side chains link individual amino acids to form linear protein molecules,allowing amine and carboxyl groups to determine protein shape and function.
C) Amino acids vary in how much adenine,cytosine,thymine,and guanine are present,and these differences affect the protein folding that determines protein function.
D) Amino acid side chains have active and inactive forms,and the pattern of active and inactive side chains determines how the protein folds and functions.
E) Amino acids vary in the structure of their amine and carboxyl groups,and interactions among these functional groups affect protein folding and function.

Question 63

Why is DNA replication called "semiconservative"?

A) DNA is replicated,with one copy composed of the original molecule and one copy newly synthesized.
B) DNA is replicated,each copy having one strand of the original molecule and one newly synthesized strand.
C) DNA is replicated,each copy having one strand of DNA and one strand of RNA containing uracil.
D) DNA is replicated,the process following strict base-pairing rules where A pairs with T and C pairs with G.
E) DNA is replicated,the process always proceeding in a 5' to 3' direction and driven by polymerase molecules.

Question 64

What molecule provides long-term energy storage in the body?

A) glycerol
B) glycogen
C) fatty acid
D) phospholipid
E) triglyceride

Question 65

Select the statements that best describe how nucleotides pair with one another in a DNA molecule.Select the TWO answers that are correct.

A) Nucleotides pair with each other to form the backbone of a single DNA strand.
B) Adenine pairs with thymine,and guanine pairs with cytosine.
C) Adenine pairs with guanine,and thymine pairs with cytosine.
D) Nucleotides pair with each other,joining two strands of DNA by covalent bonding.
E) Nucleotides pair with each other,joining two strands of DNA by hydrogen bonding.

Question 66

Why is photosynthesis important to both plants and animals? Select the TWO answers that are correct.

A) It produces water.
B) It produces oxygen.
C) It produces lactate.
D) It produces glucose.
E) It produces pyruvate.

Question 67

What molecule provides short-term energy storage in the body?

A) glycine
B) glycerol
C) glucose
D) glucagon
E) glycogen

Question 68

Select the statement that best describes the function of heating and cooling in PCR.

A) Heating facilitates strand denaturation,and cooling facilitates primer attachment.
B) Heating facilitates primer attachment,and cooling facilitates strand elongation.
C) Heating facilitates strand elongation,and cooling facilitates strand denaturation.
D) Heating facilitates strand denaturation,and cooling facilitates strand elongation.
E) Heating facilitates strand elongation,and cooling facilitates primer attachment.

Question 69

What is the function of DNA?

A) transfers genetic information from the nucleus to the cytoplasm
B) lowers the activation energy of important chemical reactions
C) activates enzymes from inactive states under specific conditions
D) stores chemically coded,heritable information in an organism
E) serves as a barrier to the environment in the cell membrane

Question 70

What chemical interactions determine how a protein folds? Select the THREE answers that are correct.

A) interactions among side chains of nucleotides
B) interactions among core structures of amino acids
C) interactions between amino acids and nucleotides
D) interactions among side chains of amino acids
E) interactions between amino acid side chains and water

Question 71

Select the best description of a short tandem repeat.

A) a nucleotide sequence of at least two bases that is continuously repeated at least 30 times in a DNA strand
B) a nucleotide sequence of at least three bases that is continuously repeated in a DNA strand
C) a nucleotide sequence of at least two bases that is continuously repeated in a DNA strand
D) a nucleotide sequence of at least two bases that is discontinuously repeated in a DNA strand
E) a nucleotide sequence of at least three bases that is discontinuously repeated in a DNA strand

Question 72

What products of aerobic respiration are used in photosynthesis? Select the TWO answers that are correct.

A) NADH
B) lactic acid
C) oxygen
D) water
E) carbon dioxide

Question 73

What are the functions of the protein ends of spidroin? Select the THREE answers that are correct.

A) stability in water
B) confer flexibility
C) secretion from the cell
D) enhance protein strength
E) assembly into silk-fibers

Question 74

Why can the same short tandem repeat region vary in length between the two copies of a chromosome of an individual?

A) Each chromosome is inherited from a different parent.
B) Variation prevents the propagation of copy errors.
C) DNA replication is an imperfect process.
D) STR regions are modified during transcription.
E) Differences signal polymerase to bind to the correct strand.

Question 75

How is DNA stored in eukaryotic cells? Select the TWO answers that are correct.

A) DNA is sequestered in the nucleus apart from the metabolic activity of the cytoplasm.
B) DNA is stored as multiple double-stranded molecules formed into chromosomes.
C) DNA is stored as chromosomes consisting of a single DNA molecule and no protein molecules.
D) DNA is a linear molecule wrapped around proteins and condensed into chromosomes.
E) DNA is a circular molecule that is free-floating in the cytoplasm of the cell.

Question 76

Select the statements that correctly describe how a new DNA molecule reflects the original DNA molecule from which it was copied.Select the TWO answers that are correct.

A) DNA replication proceeds in a 5' to 3' direction in the new DNA molecule and in the opposite direction in the original.
B) The nitrogenous bases in the new DNA molecule are A,T,G,and C,but the original molecule contains A,U,G,and C.
C) Each new DNA molecule contains an original strand and a newly synthesized strand.
D) The two DNA molecules are exact opposites of each other according to base pairs.
E) Base pairing rules duplicate the base pairs of the original molecule in the new molecule.

Question 77

What factor does gel electrophoresis use to separate DNA molecules?

A) concentration of protein in the DNA molecules
B) concentration of G-C pairs in the DNA molecules
C) amount of positive charge on the DNA molecules
D) concentration of A-T pairs in the DNA molecules
E) length of individual DNA molecules

Question 78

Why does DNA travel toward the positive electrode during gel electrophoresis?

A) DNA is positively charged,and like charges attract.
B) DNA is neutral,but it associates with negatively charged RNA.
C) DNA is neutral,but it associates with negatively charged proteins.
D) DNA is negatively charged,and opposite charges attract.
E) DNA is neutral,but it associates with positively charged proteins.

Question 79

What is the polymerase chain reaction (PCR)?

A) PCR selects variations of genes within DNA,called alleles,to increase the fitness of organisms by artificial selection.
B) PCR produces many copies of a DNA sequence from a small sample using temperature cycling,primers,free nucleotides,and polymerase enzymes.
C) PCR modifies DNA within organisms,often species of agricultural importance,to increase the occurrence of desirable traits.
D) PCR determines the base pairs in a DNA sequence using temperature cycling,primers,fluorescent dye labels,and polymerase enzymes.
E) PCR amplifies DNA within an organism to increase the expression of that DNA for the purpose of studying its effects.

Question 80

Select the parts that make up the backbone of the DNA molecule.Select the TWO answers that are correct.

A) nucleoside
B) glycine
C) phosphate
D) sugar
E) nitrogenous base