Bio 101 Exam 3 Review
Correct answers are marked with *
Chapter 6 Enzymes
1. Which of the following statements is false?
A. Anabolism + catabolism = metabolism
B. ATP ADP + P + energy is a catabolic reaction
C. ADP + P + energy ATP is an anabolic reaction
D. 3 Fatty acids + 1 glycerol + ATP 1 Triglyceride + 3 H
2
O + ADP + P is an anabolic reaction
E. All are true*
3. Chemical reactions that break down complex molecules into simpler molecules and usually release energy are:
A. Dehydration reactions
B. Reduction reactions
C. Anabolic reactions
D. Metabolic reactions
E. Catabolic reactions*
5. All of the following will increase the rate of a chemical reaction except
A. an enzyme
B. decreasing temperature*
C. smaller size molecules
D. all increase the rate of a reaction
6. What is an enzyme?
A. A biological catalyst
B. The same thing as a substrate
C. An intermediate in a catabolic pathway
D. A molecule that speeds up chemical reactions
E. Both A and D are correct*
7. Enzymes are usually:
A. Proteins*
B. Lipids
C. Carbohydrates
D. Nucleic acids
E. Electrolytes

8. Which of the following statements regarding enzymes is false?
A. Enzymes are not used up in a chemical reaction
B. Enzymes decrease the activation energy required for a reaction
C. Enzymes increase the probability of a reaction
D. Enzymes function as electron acceptors in oxidation-reduction reactions*
E. All of the statements are true, none are false
9. An enzyme/substrate complex yields a product and
A. hydrogen
B. an unchanged enzyme*
C. a denatured enzyme
D. a substrate
10. A coenzyme is:
A. The second enzyme in a reaction that requires two enzymes
B. One of several enzymes in a multi-step metabolic pathway
C. The nonprotein part of a holoenzyme*
D. The same thing as an apoenzyme
11. The specificity of an enzyme is determined by:
A. The active site*
B. The coenzyme
C. The product
D. The allosteric site
E. The substrate
12. The allosteric site is where:
A. The substrate binds
B. The product is released
C. A competitive inhibitor binds
D. The coenzyme binds
E. A noncompetitive inhibitor binds*
13. Feedback inhibition occurs when:
A. The substrate blocks the active site
B. The feedback inhibitor binds to the active site
C. The product binds to the allosteric site*
D. The feedback inhibitor binds to the coenzyme
14. Which of the following is least likely to decrease enzyme activity?
A. Too much heat
B. Too much acid
C. Too much base
D. Too much salt
E. Too much substrate*

15. Look at the following diagram: If the arrows represent chemical reactions, the letters A-D represent substrates and products, and e1, e2, and e3 represent the enzymes that catalyze the chemical reactions, then which of the following statements is not supported by the information given?
A. The entire diagram represents a metabolic pathway
B. A is a substrate, B is a product
C. B is the substrate for the second chemical reaction
D. An organism that has this pathway present will have genes that code for enzymes to catalyze each step of the pathway
E. This is an anabolic pathway*
Chapter 7 Photosynthesis
1. The general equation sunlight + H
2
O + CO
2
O
2
+ sugar is the equation for:
A. Cellular respiration
B. Photophosphorylation
C. The Calvin-Benson cyclen
D. Photosynthesis*
2. Photosynthesis makes the energy from light available to organisms that eat photosynthetic organisms. What form is that energy in?
A. The carbon atoms of glucose
B. ATP
C. Chemical energy stored in the bonds that hold the carbon atoms of glucose together*
D. NADPH
3. The green pigments in plants are:
A. Thylakoids
B. Chlorophyll a and b*
C. Carotenoids
D. Stomata
4. The thylakoids contain:
A. Photosynthetic pigments
B. Electron transport chains
C. ATP synthase
D. Enzymes of the Calvin-Benson cycle
E. A and B
F. B and C
G. A, B, and C*

5. What does the Calvin-Benson cycle require?
A. ATP and NADPH
B. NADH and FADH
2
C. Sugar
D. Carbon dioxide and water
E. Energy, electrons, and carbon dioxide*
6. In cyclic electron flow where do the electrons come from?
A. NADPH
B. Sunlight
C. Chlorophyll*
D. NADH and FADH
2
E. Water
7. What is the final electron acceptor in cyclic electron flow?
A. NADPH
B. Sunlight
C. Chlorophyll*
D. NADH and FADH
2
E. Water
8. In noncyclic electron flow where do the electrons come from?
A. NADPH
B. Sunlight
C. Chlorophyll
D. NADH and FADH
2
E. Water*
9. What is the final electron acceptor in noncyclic electron flow?
A. NADP*
B. Sunlight
C. Chlorophyll
D. NAD and FAD
E. Water
10. What does noncyclic electron flow provide for the Calvin-Benson cycle?
A. ATP
B. NADPH
C. ATP and NADPH*
D. NADH and FADH
2
E. Oxygen
F. Water
11. What does cyclic electron flow provide for the Calvin-Benson cycle?
A. ATP*
B. NADPH

C. ATP and NADPH
D. NADH and FADH
2
E. Oxygen
F. Water
12. Why do you need both cyclic and noncyclic electron flow if one provides everything you need to run the Calvin-Benson cycle?
A. The Calvin-Benson cycle requires more NADPH than ATP
B. The Calvin-Benson cycle requires more ATP than NADPH*
C. To provide carbon dioxide
D. To provide oxygen
E. To use up excess water
13. A photosystem consists of:
A. ATP, NADPH, and carbon dioxide
B. A source of light, a source of carbon, and an electron carrier
C. Light absorbing pigments, a reaction center, and a primary electron acceptor*
14. The reaction center:
A. Transfers solar energy to a high energy electron
B. Takes a high energy electron and passes it down a membrane to NADP
C. Passes a high energy electron to the primary electron acceptor*
D. Splits water to provide electrons to the electron transport chain
15. The photosynthetic pigments:
A. Transfer solar energy to a high energy electron*
B. Take a high energy electron and pass it down a membrane to NADP
C. Pass a high energy electron to the primary electron acceptor
D. Split water to provide electrons to the electron transport chain
16. The primary electron acceptor:
A. Transfers solar energy to a high energy electron
B. Takes a high energy electron and passes it down a membrane to NADP*
C. Passes a high energy electron to the primary electron acceptor
D. Splits water to provide electrons to the electron transport chain
17. Where do the electrons to reduce carbon dioxide in the Calvin-Benson cycle come from?
A. NADPH*
B. NADH and FADH
2
C. ATP
D. Carbon dioxide isn’t reduced in the Calvin-Benson cycle, it is oxidized

18. What does reduction of carbon dioxide in the Calvin-Benson cycle provide?
A. Oxygen
B. Rubisco
C. Ribulose bisphosphate (RuBP)
D. Glyceraldehyde-3-phosphate (G3P) *
E. ATP
19. What does carbon dioxide combine with in the Calvin-Benson cycle?
A. Rubisco
B. Glyceraldehyde-3-phosphate (G3P)
C. Phosphoenol pyruvate (PEP)
D. Ribulose bisphosphate (RuBP) *
20. What is photorespiration?
A. When stomata close to prevent water loss and oxygen levels rise and carbon dioxide levels fall in mesophyll cells*
B. When the light reactions are used to produce ATP from NADPH
C. When the Calvin-Benson cycle is reversed to oxidize G3P and make ATP and
NADPH
D. There is no such thing
21. What is the problem with photorespiration?
A. Nothing, it’s great
B. NADPH can’t donate electrons to the electron transport chain
C. It turns the light reactions into a useless energy cycle
D. Oxygen binds to RuBP and only one 3PG molecule is produced by the Calvin-
Benson cycle*
22. How do C4 plants overcome photorespiration?
A. Fix CO
2
to PEP in mesophyll cells, release CO
2
into bundle sheath cells*
B.
They don’t use RuBP
C. Generate a four carbon molecule from the Calvin-Benson cycle
D. Don’t have chloroplasts
E. Fix CO
2
to PEP in mesophyll cells at night, release CO
2
during the day
23. How do CAM plants overcome photorespiration?
A. Fix CO
2
to PEP in mesophyll cells, release CO
2
into bundle sheath cells
B.
They don’t use RuBP
C. Generate a four carbon molecule from the Calvin-Benson cycle
D. Don’t have chloroplasts
E. Fix CO
2
to PEP in mesophyll cells at night, release CO
2
during the day*

Chapter 8 Cellular Respiration
1. In aerobic cellular respiration the final electron acceptor is:
A. H
2
O
B. ATP
C. C O
2
D. NAD
+
E. O
2
*
2. In anaerobic cellular respiration the final electron acceptor is:
A. C O
2
B. O
2
C. An organic molecule (pyruvate, typically)
D. An inorganic molecule other than O
2
*
3. In fermentation the final electron acceptor is:
A. CO₂
B. O₂
C. An organic molecule (pyruvate, typically)*
D. An inorganic molecule other than O
2
4. In cellular respiration chemiosmosis is powered by a proton gradient that is set up by:
A. Substrate level phosphorylation
B. Lactic acid synthesis
C. CO
2
fixation
D. Reduction of oxidized chlorophyll
E. High energy electrons obtained from the oxidation of organic molecules*
5. Substrate level phosphorylation is:
A. The indirect transfer of high energy phosphate molecules down a chain of carriers and eventually on to ADP
B. Direct transfer of phosphate from a substrate to ADP*
C. Direct transfer of phosphate from ATP to a substrate
D. The same as chemiosmosis
6. The process that involves transfer of electrons from organic compounds down an electron transport chain to a final electron acceptor and harnessing the energy released during electron transfer to make ATP by chemiosmosis is:
A. Substrate level phosphorylation
B. Photophosphorylation
C. Oxidative phosphorylation*

7. In oxidative phosphorylation high energy electrons are obtained by:
A. Oxidation of organic compounds*
B. Oxidation of chlorophyll
C. Excitement by light
D. Oxidation of ATP
E. Chemiosmosis
8. In photophosphorylation high energy electrons are obtained by:
A. Oxidation of organic compounds
B. Oxidation of chlorophyll
C. Excitement by light*
D. Oxidation of ATP
9. In fermentation high energy electrons are obtained by:
A. Oxidation of organic compounds*
B. Oxidation of chlorophyll
C. Excitement by light
D. Oxidation of ATP
10. In fermentation high energy electrons are used to make ATP.
A. True
B. False*
11. In fermentation, ATP is generated by:
A. Oxidative phosphorylation
B. Photophosphorylation
C. Substrate level phosphorylation*
D. Magic
E. Wishful thinking
12. Which of the following statements about the Krebs cycle is not correct?
A. The process occurs in the mitochondria
B. The major end product of the cycle is lactic acid*
C. At several steps, hydrogen and electrons are removed from substrate molecules
D. Acetyl-CoA enters the cycle
E. All are true
13. Which of the following best describes glycolysis?
A. Conversion of glucose into carbon dioxide and water
B. Conversion of glucose into two molecules of pyruvic acid*
C. Conversion of pyruvic acid into carbon dioxide and water
D. Formation of sugar

14. During aerobic cellular respiration, electrons are passed down the electron transport chain and is formed.
A. Oxygen
B. Water*
C. Glycogen
D. NADH
2
15. If oxygen is lacking, how many net ATP are produced by the oxidation of one
molecule of glucose?
A. 0
B. 2*
C. 8
D. 38
16. 2-c molecule enters
A. Glycolysis
B. Electron transport chain
C. Krebs cycle*
D. All of these
17. Glucose serves as the initial substrate
A. Glycolysis*
B. Electron transport chain
C. Krebs cycle
D. All of these
18. Involves the formation of a 6-carbon molecule and its successive degradation to a
4-carbon pickup molecule
A. Glycolysis
B. Electron transport chain
C. Krebs cycle*
D. All of these
19. Involves the removal and or transfer of hydrogen or electrons from another
molecule
A. Glycolysis
B. Electron transport chain
C. Krebs cycle
D. All of these*
20. Catabolizes fatty acid part of a triglyceride after the fatty acid chain has been broken down to 2-carbon subunits
A. Glycolysis
B. Electron transport chain
C. Krebs cycle*
D. All of these

21. Catabolizes the glycerol part of a triglyceride after the fatty acid chains have been removed
A. Glycolysis*
B. Electron transport chain
C. Krebs cycle
D. All of these
22. Results in the formation of pyruvic acid molecules
A. Glycolysis*
B. Electron transport chain
C. Krebs cycle
D. All of these
23. Occurs in the cytoplasm of the cell, but not in mitochondrion
A. Glycolysis*
B. Electron transport chain
C. Krebs cycle
D. All of these
24. Makes ATP
A. Glycolysis
B. Electron transport chain
C. Krebs cycle
D. All of these*
25. May occur under totally anaerobic conditions
A. Glycolysis*
B. Electron transport chain
C. Krebs cycle
D. All of these
26. Involves NAD
A. Glycolysis
B. Electron transport chain
C. Krebs cycle
D. All of these*
27. How many ATPs can be made from FADH
2
?
A. 38
B. 8
C. 3
D. 2*
E. 4

28. Fatty acids are broken down by the process
A. Glycolysis
B. Ketosis
C. Beta oxidation*
D. Gluconeogenesis
29. Glucose can be made from fat.
A. True
B. False*
30. The body will convert excess glucose into
A. Pyruvate
B. Lactate
C. Oxaloacetate
D. Protein
E. Fat*
31. Gluconeogenesis is
A. Formation of fats
B. Making glucose from other substances*
C. Breaking down glucose
D. Making proteins from glucose
E. Making fats from glucose
32. Citrate is an important intermediate in this pathway:
A. Glycolysis
B. Kreb's cycle*
C. Pentose phosphate
D. Electron transport chain