AP Biology Exam Review Practice Questions and
Answers
DNA/Biochemestry Test
--
1. The digestive enzyme pepsin works in the acidic environment of the stomach to hydrolyze peptide
bonds. On which macromolecules does pepsin act?
A. carbohydrate
B. protein
C. DNA
D. lipid
B. Protein
2. Egg whites consist primarily of water and the protein albumin. When you fry an egg, why does the
egg white turn from clear to white?
A. The protein becomes dissociated.
B. The protein acquires tertiary structure.
C. The protein becomes denatured.
D. The protein becomes dehydrated
C. The Protein becomes denatured
3. Margarine is made by hydrogenating vegetable oils so that they take on the consistency of butter.
Which of the following is the chemical basis for this change from a liquid to a solid?
A. Fats are changed from unsaturated to saturated, allowing them to solidify.
B. Fats are changed from saturated to unsaturated, allowing them to solidify.
C. Trans-fatty acids are changed from unsaturated to saturated, allowing them to solidify.
D. Trans fatty acids are changed from saturated to unsaturated, allowing them to solidify.
A. Fats are changed from unsaturated to saturated, allowing them to solidify.
4. People who are lactose intolerant can often consume some products made from milk such as
cheese and yogurt. By comparison, people with a true milk allergy, which involves an immune
response to milk protein, cannot consume milk or products made from milk. Given this information,
which of the following statements is true?
A. The protein that causes a true milk allergy is lactose. B. All people who are lactose intolerant are
also allergic to milk.
C. Yogurt contains live and active cultures of Lactobacillus acidophilus bacteria and therefore prevents
an allergic response in people with a true milk allergy.
D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.
D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.
5. Shivering is the result of uncontrollable contractions of skeletal muscle tissue in an effort to
increase heat production and raise body temperature. How does this process relate to ATP
hydrolysis?
A. ATP is converted directly to heat.
B. Muscle contractions in the form of shivering produces heat and warms the body.
C. ATP hydrolysis causes muscle contraction.
D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted
into heat.
D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted
into heat.
,6. Hemoglobin is a protein composed of four subunits, each with a binding site for oxygen. When a
molecule of O2 binds to any one of the subunits, the affinity of the other three subunits for O2 is
increased. What role is oxygen playing in this process?
A. enzyme
B. allosteric activator
C. allosteric inhibitor
D. substrate
B. allosteric activator
7. While conducting an experiment, you realize that a competitive inhibitor was interfering with your
reaction. To overcome this problem, you
A. add a non-competitive inhibitor to the reaction.
B. decrease the concentration of the correct substrate in the reaction.
C. increase the concentration of the correct substrate in the reaction.
D. add an allosteric activator to the reaction.
C. increase the concentration of the correct substrate in the reaction.
8. After getting off the ski lift, you choose a trail that requires you to ski up a small incline before
beginning the downward section of the trail. In this scenario, the hill is analogous to
A. free energy.
B. potential energy.
C. kinetic energy.
D. activation energy.
D. activation energy.
9. A new antibiotic has been developed that will use noncompetitive inhibitor enzyme inhibition. This
means that the
A. antibiotic will bind to the enzyme and alter the shape of the enzyme.
B. antibiotic will bind to the substrate and alter the shape of the substrate.
C. antibiotic will bind to the enzyme-substrate complex and alter its shape.
D. antibiotic will bind to the product that is being produced and alter its shape.
E. antibiotic will bind to the receptor proteins embedded in the phospholipid bilayer, which will in
turn close the channels.
A. antibiotic will bind to the enzyme and alter the shape of the enzyme.
10. Nucleic acids are created with
A. phosphodiester bonds
B. peptide bonds
C. a phosphate and two fatty acids bonded to glycerol
D. sugar polymers
A. phosphodiester bonds
11. Which of the following best depicts a diagram of enzymes and substrates when they react?
Assume only forward reactions. Use the following to make your choice: E = enzyme, S = substrate, ES
= enzyme-substrate complex, P = products.
A. E + P -> ES
B. E + S -> ES + P
C. E + S -> ES -> E + P
D. E + ES -> P + E
E. E + P -> EP -> S + E
C. E + S -> ES -> E + P
,12. Which of the following is responsible for the cohesive property of water?
A. Hydrogen bonds between the oxygen atoms of two adjacent water molecules.
B. Covalent bonds between the hydrogen atoms of two adjacent water molecules.
C. Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
D. Covalent bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
E. Hydrogen bonds between water molecules and other types of molecules.
C. Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
13. Which of the following best describes the reaction shown below?
AB -> A + B + energy
A. Hydrolysis
B. An exergonic reaction
C. catabolism
D. An endergonic reaction
E. a, b, and c only
E. a, b, and c only
14. The 20 different amino acids found in polypeptides exhibit different chemical and physical
properties because of different:
A. side chains (R groups).
B. amino groups.
C. tertiary structure.
D. carboxyl groups.
E. Both A and B are correct.
A. side chains (R groups).
15. Lipids are the only class of macromolecules that contain
A. amino acids.
B. nucleic acids.
C. fatty acids.
D. phosphate groups.
E. sugars.
C. fatty acids.
16. At the conclusion of an enzyme catalyzed reaction, the enzyme
A. must be resynthesized from its amino acids.
B. frees itself from the product and is ready to be reused.
, C. must be transported from outside of the cell.
D. changes into an active form.
E. closes up its active site and cannot bind to more substrate.
B. frees itself from the product and is ready to be reused.
17. You arrive late to a biological seminar. However, just as you enter the room, you hear the speaker
referring to the "amino end" and the "carboxyl end" of a macromolecule. Immediately, you know that
they are talking about a
A. carbohydrate.
B. protein.
C. DNA.
D. lipid
B. protein.
18. The inorganic non-protein components that participate in enzyme catalysis are known as
A. coenzymes.
B. cofactors.
C. end-products.
D. substrates.
E. reactants.
B. Cofactors
19. When the substrate is bound to the enzyme, the shape of the enzyme may change slightly, leading
to
A. a better induced fit.
B. a great range of possible catalytic activities.
C. a greater supply of activation energy.
D. more permanent binding through intimate total contact.
E. more possible products of the reaction.
A. a better induced fit.
20. The ability of an enzyme to catalyze a reaction is not affected by
A. temperature.
B. pH.
C. salt concentration.
D. binding of specific regulatory molecules.
E. excess cofactor.
E. excess cofactor.
21. Macromolecules are disassembled in ____________ reactions.
A. anabolic
B. hydrolysis
C. radioactive
D. denaturation
E. dehydration
B. hydrolysis
22. DNA, RNA, and ATP contain monomers known as
A. peptides.
B. enzymes.
C. amino acids.
Answers
DNA/Biochemestry Test
--
1. The digestive enzyme pepsin works in the acidic environment of the stomach to hydrolyze peptide
bonds. On which macromolecules does pepsin act?
A. carbohydrate
B. protein
C. DNA
D. lipid
B. Protein
2. Egg whites consist primarily of water and the protein albumin. When you fry an egg, why does the
egg white turn from clear to white?
A. The protein becomes dissociated.
B. The protein acquires tertiary structure.
C. The protein becomes denatured.
D. The protein becomes dehydrated
C. The Protein becomes denatured
3. Margarine is made by hydrogenating vegetable oils so that they take on the consistency of butter.
Which of the following is the chemical basis for this change from a liquid to a solid?
A. Fats are changed from unsaturated to saturated, allowing them to solidify.
B. Fats are changed from saturated to unsaturated, allowing them to solidify.
C. Trans-fatty acids are changed from unsaturated to saturated, allowing them to solidify.
D. Trans fatty acids are changed from saturated to unsaturated, allowing them to solidify.
A. Fats are changed from unsaturated to saturated, allowing them to solidify.
4. People who are lactose intolerant can often consume some products made from milk such as
cheese and yogurt. By comparison, people with a true milk allergy, which involves an immune
response to milk protein, cannot consume milk or products made from milk. Given this information,
which of the following statements is true?
A. The protein that causes a true milk allergy is lactose. B. All people who are lactose intolerant are
also allergic to milk.
C. Yogurt contains live and active cultures of Lactobacillus acidophilus bacteria and therefore prevents
an allergic response in people with a true milk allergy.
D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.
D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.
5. Shivering is the result of uncontrollable contractions of skeletal muscle tissue in an effort to
increase heat production and raise body temperature. How does this process relate to ATP
hydrolysis?
A. ATP is converted directly to heat.
B. Muscle contractions in the form of shivering produces heat and warms the body.
C. ATP hydrolysis causes muscle contraction.
D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted
into heat.
D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted
into heat.
,6. Hemoglobin is a protein composed of four subunits, each with a binding site for oxygen. When a
molecule of O2 binds to any one of the subunits, the affinity of the other three subunits for O2 is
increased. What role is oxygen playing in this process?
A. enzyme
B. allosteric activator
C. allosteric inhibitor
D. substrate
B. allosteric activator
7. While conducting an experiment, you realize that a competitive inhibitor was interfering with your
reaction. To overcome this problem, you
A. add a non-competitive inhibitor to the reaction.
B. decrease the concentration of the correct substrate in the reaction.
C. increase the concentration of the correct substrate in the reaction.
D. add an allosteric activator to the reaction.
C. increase the concentration of the correct substrate in the reaction.
8. After getting off the ski lift, you choose a trail that requires you to ski up a small incline before
beginning the downward section of the trail. In this scenario, the hill is analogous to
A. free energy.
B. potential energy.
C. kinetic energy.
D. activation energy.
D. activation energy.
9. A new antibiotic has been developed that will use noncompetitive inhibitor enzyme inhibition. This
means that the
A. antibiotic will bind to the enzyme and alter the shape of the enzyme.
B. antibiotic will bind to the substrate and alter the shape of the substrate.
C. antibiotic will bind to the enzyme-substrate complex and alter its shape.
D. antibiotic will bind to the product that is being produced and alter its shape.
E. antibiotic will bind to the receptor proteins embedded in the phospholipid bilayer, which will in
turn close the channels.
A. antibiotic will bind to the enzyme and alter the shape of the enzyme.
10. Nucleic acids are created with
A. phosphodiester bonds
B. peptide bonds
C. a phosphate and two fatty acids bonded to glycerol
D. sugar polymers
A. phosphodiester bonds
11. Which of the following best depicts a diagram of enzymes and substrates when they react?
Assume only forward reactions. Use the following to make your choice: E = enzyme, S = substrate, ES
= enzyme-substrate complex, P = products.
A. E + P -> ES
B. E + S -> ES + P
C. E + S -> ES -> E + P
D. E + ES -> P + E
E. E + P -> EP -> S + E
C. E + S -> ES -> E + P
,12. Which of the following is responsible for the cohesive property of water?
A. Hydrogen bonds between the oxygen atoms of two adjacent water molecules.
B. Covalent bonds between the hydrogen atoms of two adjacent water molecules.
C. Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
D. Covalent bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
E. Hydrogen bonds between water molecules and other types of molecules.
C. Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another
water molecule.
13. Which of the following best describes the reaction shown below?
AB -> A + B + energy
A. Hydrolysis
B. An exergonic reaction
C. catabolism
D. An endergonic reaction
E. a, b, and c only
E. a, b, and c only
14. The 20 different amino acids found in polypeptides exhibit different chemical and physical
properties because of different:
A. side chains (R groups).
B. amino groups.
C. tertiary structure.
D. carboxyl groups.
E. Both A and B are correct.
A. side chains (R groups).
15. Lipids are the only class of macromolecules that contain
A. amino acids.
B. nucleic acids.
C. fatty acids.
D. phosphate groups.
E. sugars.
C. fatty acids.
16. At the conclusion of an enzyme catalyzed reaction, the enzyme
A. must be resynthesized from its amino acids.
B. frees itself from the product and is ready to be reused.
, C. must be transported from outside of the cell.
D. changes into an active form.
E. closes up its active site and cannot bind to more substrate.
B. frees itself from the product and is ready to be reused.
17. You arrive late to a biological seminar. However, just as you enter the room, you hear the speaker
referring to the "amino end" and the "carboxyl end" of a macromolecule. Immediately, you know that
they are talking about a
A. carbohydrate.
B. protein.
C. DNA.
D. lipid
B. protein.
18. The inorganic non-protein components that participate in enzyme catalysis are known as
A. coenzymes.
B. cofactors.
C. end-products.
D. substrates.
E. reactants.
B. Cofactors
19. When the substrate is bound to the enzyme, the shape of the enzyme may change slightly, leading
to
A. a better induced fit.
B. a great range of possible catalytic activities.
C. a greater supply of activation energy.
D. more permanent binding through intimate total contact.
E. more possible products of the reaction.
A. a better induced fit.
20. The ability of an enzyme to catalyze a reaction is not affected by
A. temperature.
B. pH.
C. salt concentration.
D. binding of specific regulatory molecules.
E. excess cofactor.
E. excess cofactor.
21. Macromolecules are disassembled in ____________ reactions.
A. anabolic
B. hydrolysis
C. radioactive
D. denaturation
E. dehydration
B. hydrolysis
22. DNA, RNA, and ATP contain monomers known as
A. peptides.
B. enzymes.
C. amino acids.
