Question 1

After several weeks of no rain during the summer, you observe that leaves of some plants are wilted. Which of the following would you expect to observe at the cellular level with respect to photosynthesis?

Accepted Answer

A)  More glucose is going to be produced to compensate for the absence of water.
B)  The rate of the oxidation and reduction of the thylakoid electron transport chain will be greater than normal.
C)  More CO2 will be incorporated into carbohydrate.
D)  More ATP is going to be synthesized by ATP synthase in the chloroplasts.
E)  The rate of the reduction of chlorophyll molecules will be decreased.F) None of the above
G) C) and E)

Question 2

Which of the following statements is TRUE regarding the Calvin cycle?

Accepted Answer

A)  The Calvin cycle is considered a "dark" reaction, because it is not directly related to photosynthesis.
B)  The Calvin cycle is a carefully regulated process because excess starch can be toxic to plant cells.
C)  The Calvin cycle uses a rare (and thus "rate-limiting") enzyme called rubisco.
D)  The action of rubisco is all that is necessary to produce high-energy triose phosphate from O2.
E)  None of the other answer options is correct.F) B) and C)
G) A) and C)

Question 3

Prokaryotes account for roughly half of terrestrial photosynthesis.

Accepted Answer

A) True 
 B)False

Question 4

Cyclic electron transport enhances ATP production because:

Accepted Answer

A)  ADP production increases.
B)  electrons are transferred from ferredoxin to plastoquinone.
C)  proton translocation decreases.
D)  photosystem I pumps more protons.
E)  cyclic electron transport is more energy efficient than linear electron transport.F) D) and E)
G) A) and C)

Question 5

Suppose you discovered a mutant strain of spinach in which the thylakoid membranes were slightly permeable to protons, thus allowing a slow leakage (remember that normal membranes are not permeable to protons at all) . What change in the reactions of photosynthesis might occur in compensation for this defect?

Accepted Answer

A)  Cyclic electron transport would increase.
B)  Noncyclic electron transport would increase.
C)  O2 production would decrease.
D)  Cyclic electron transport would decrease.
E)  Noncyclic electron transport would decrease.F) D) and E)
G) None of the above

Question 6

If plants are exposed to a toxin that makes the thylakoid membrane leaky to protons, predict the rate of ATP production by the plants.

Accepted Answer

A)  ATP production will increase.
B)  ATP production will decrease.
C)  ATP production does not change.D) A) and B)
E) None of the above

Question 7

The experiment in Fig. 8.3 demonstrates that the percentage of 18O2 increases when the:

18O2 increases when the:     A) water in the experiment contains 18O2. B) carbon dioxide in the experiment contains 18O2. C) water and carbon dioxide in the experiment both contain 18O2." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  water in the experiment contains 18O2.
B)  carbon dioxide in the experiment contains 18O2.
C)  water and carbon dioxide in the experiment both contain 18O2.D) A) and B)
E) All of the above

Question 8

What is the INITIAL carbon input in the Calvin cycle?

Accepted Answer

A)  C6H12O6
B)  triose phosphate
C)  CO2
D)  rubiscoE) All of the above
F) A) and D)

Question 9

Which of the following is part of the photosynthetic electron transport chain between photosystems I and II?

Accepted Answer

A)  plastocyanin
B)  plastoquinone
C)  cytochrome b6f complex
D)  All of these choices are correct.E) B) and D)
F) B) and C)

Question 10

How many molecules of NADPH are required for 12 molecules of RuBP to be carboxylated by rubisco?

Accepted Answer

A)  10
B)  12
C)  24
D)  36
E)  None of the other answer options is correct.F) A) and C)
G) A) and D)

Question 11

In plants and algae, which of the following is a by-product of photosynthesis?

Accepted Answer

A)  O2
B)  CO2
C)  carbohydrates
D)  C6H12O6
E)  H+F) A) and B)
G) A) and E)

Question 12

During photosynthesis in plants and algae, _____ is oxidized and _____ is reduced.

Accepted Answer

A)  O2; CO2
B)  CO2; H2O
C)  H2O; O2
D)  H2O; CO2
E)  NADPH; ATPF) C) and D)
G) A) and B)

Question 13

Which of the following is the primary advantage to eukaryotic photosynthetic organisms of having two photosystems?

Accepted Answer

A)  Twice as much ATP can be made compared to cells with a single photosystem.
B)  Twice as much NADPH can be made compared to cells with a single photosystem.
C)  Twice as much oxygen can be made compared to cells with a single photosystem.
D)  Water can be used as source of electrons.
E)  ATP can be synthesized by ATP synthase.F) A) and B)
G) A) and C)

Question 14

The reactions of the Calvin cycle used to be referred to as the "dark reactions" of photosynthesis, implying that light was not required for this pathway to incorporate CO2 into carbohydrate. However, in the absence of light the Calvin cycle shuts down. Which of the following parts of the Calvin cycle would be impacted FIRST by the absence of light energy?

Accepted Answer

A)  the reduction of 3-phosphoglycerate and the regeneration of RuBP
B)  the carboxylation of RuBP and the reduction of 3-phosphoglycerate
C)  the carboxylation of RuBP and the regeneration of RuBP
D)  the carboxylation of RuBP and the synthesis of hexose sugarsE) B) and C)
F) A) and D)

Question 15

ATP production in photosynthesis requires:

Accepted Answer

A)  light.
B)  electrons.
C)  protons.
D)  light and protons.
E)  light, electrons, and protons.F) B) and C)
G) D) and E)

Question 16

Which of the following could be TRUE if a plant cell is exposed to a toxin that makes the thylakoid membrane freely permeable to protons?

Accepted Answer

A)  There would be no ATP available to drive carbohydrate synthesis in the Calvin cycle.
B)  There would be no ATP needed to split water molecules early in the light-dependent pathway.
C)  There would be no ATP produced in the chloroplasts to power photosynthesis in the absence of light energy.
D)  ATP generated by the mitochondria would be used to power photosynthesis, so plant cells would not have enough ATP left to supply the many other processes that require it.
E)  The amount of NADPH in the chloroplast would increase.F) A) and E)
G) B) and E)

Question 17

During photosynthesis, _____ is reduced to _____.

Accepted Answer

A)  water; carbon dioxide
B)  carbon dioxide; triose phosphate
C)  oxygen; water
D)  triose phosphate; oxygen
E)  carbon dioxide; oxygenF) B) and E)
G) A) and B)

Question 18

The products of the Calvin cycle are 3-carbon sugars.

Accepted Answer

A) True 
 B)False

Question 19

How much of the sun's usable energy is captured by the photosynthetic electron transport chain?

Accepted Answer

A)  close to 100%
B)  about 60%
C)  between 20% and 25%
D)  between 5% and 10%E) None of the above
F) A) and B)

Question 20

Chemicals called uncouplers can make membranes permeable to small molecules and ions. What effect might uncouplers have on photosynthesis?

Accepted Answer

A)  increased ATP production because cyclic electron transport would increase
B)  decreased ATP production because the proton gradient would increase
C)  decreased ATP production because the proton gradient would decrease
D)  decreased NADPH production because the proton gradient would increase
E)  decreased NADPH production because the proton gradient would decreaseF) C) and D)
G) A) and C)

Exam 8: Photosynthesis: Using Sunlight to Build Carbohydrates

In plants and algae, which of the following is a by-product of photosynthesis?

Correct Answer
verified

The experiment in Fig. 8.3 demonstrates that the percentage of ¹⁸O₂ increases when the:

Correct Answer
verified

During photosynthesis, _ is reduced to _.

Correct Answer
verified

ATP production in photosynthesis requires:

Correct Answer
verified

Correct Answer
verified

If plants are exposed to a toxin that makes the thylakoid membrane leaky to protons, predict the rate of ATP production by the plants.

Correct Answer
verified

Prokaryotes account for roughly half of terrestrial photosynthesis.

Correct Answer
verified

After several weeks of no rain during the summer, you observe that leaves of some plants are wilted. Which of the following would you expect to observe at the cellular level with respect to photosynthesis?

Correct Answer
verified

Which of the following is the primary advantage to eukaryotic photosynthetic organisms of having two photosystems?

Correct Answer
verified

Which of the following could be TRUE if a plant cell is exposed to a toxin that makes the thylakoid membrane freely permeable to protons?

Correct Answer
verified

Cyclic electron transport enhances ATP production because:

Correct Answer
verified

During photosynthesis in plants and algae, _ is oxidized and _ is reduced.

Correct Answer
verified

How many molecules of NADPH are required for 12 molecules of RuBP to be carboxylated by rubisco?

Correct Answer
verified

Chemicals called uncouplers can make membranes permeable to small molecules and ions. What effect might uncouplers have on photosynthesis?

Correct Answer
verified

Correct Answer
verified

The products of the Calvin cycle are 3-carbon sugars.

Correct Answer
verified

Which of the following statements is TRUE regarding the Calvin cycle?

Correct Answer
verified

How much of the sun's usable energy is captured by the photosynthetic electron transport chain?

Correct Answer
verified

Which of the following is part of the photosynthetic electron transport chain between photosystems I and II?

Correct Answer
verified

What is the INITIAL carbon input in the Calvin cycle?

Correct Answer
verified

Exam 8: Photosynthesis: Using Sunlight to Build Carbohydrates

In plants and algae, which of the following is a by-product of photosynthesis?

Correct AnswerverifiedShow Answer

The experiment in Fig. 8.3 demonstrates that the percentage of 18O2 increases when the:

Correct AnswerverifiedShow Answer

During photosynthesis, _____ is reduced to _____.

Correct AnswerverifiedShow Answer

ATP production in photosynthesis requires:

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

If plants are exposed to a toxin that makes the thylakoid membrane leaky to protons, predict the rate of ATP production by the plants.

Correct AnswerverifiedShow Answer

Prokaryotes account for roughly half of terrestrial photosynthesis.

Correct AnswerverifiedShow Answer

After several weeks of no rain during the summer, you observe that leaves of some plants are wilted. Which of the following would you expect to observe at the cellular level with respect to photosynthesis?

Correct AnswerverifiedShow Answer

Which of the following is the primary advantage to eukaryotic photosynthetic organisms of having two photosystems?

Correct AnswerverifiedShow Answer

Which of the following could be TRUE if a plant cell is exposed to a toxin that makes the thylakoid membrane freely permeable to protons?

Correct AnswerverifiedShow Answer

Cyclic electron transport enhances ATP production because:

Correct AnswerverifiedShow Answer

During photosynthesis in plants and algae, _____ is oxidized and _____ is reduced.

Correct AnswerverifiedShow Answer

How many molecules of NADPH are required for 12 molecules of RuBP to be carboxylated by rubisco?

Correct AnswerverifiedShow Answer

Chemicals called uncouplers can make membranes permeable to small molecules and ions. What effect might uncouplers have on photosynthesis?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The products of the Calvin cycle are 3-carbon sugars.

Correct AnswerverifiedShow Answer

Which of the following statements is TRUE regarding the Calvin cycle?

Correct AnswerverifiedShow Answer

How much of the sun's usable energy is captured by the photosynthetic electron transport chain?

Correct AnswerverifiedShow Answer

Which of the following is part of the photosynthetic electron transport chain between photosystems I and II?

Correct AnswerverifiedShow Answer

What is the INITIAL carbon input in the Calvin cycle?

Correct AnswerverifiedShow Answer

Correct Answer
verified

The experiment in Fig. 8.3 demonstrates that the percentage of ¹⁸O₂ increases when the:

Correct Answer
verified

During photosynthesis, _ is reduced to _.

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

During photosynthesis in plants and algae, _ is oxidized and _ is reduced.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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