Question 1

The third stage of the three-stage Calvin cycle

Accepted Answer

A)  uses ATP and NADPH from the light reactions. 
B)  generates a glucose molecule for the plant. 
C)  is similar to the reactions found in the glycolysis pathway. 
D)  regenerates a C5 sugar for the Calvin cycle to continue. 
A)  uses ATP and NADPH from the light reactions. 
B)  generates a glucose molecule for the plant. 
C)  is similar to the reactions found in the glycolysis pathway. 
D)  regenerates a C5 sugar for the Calvin cycle to continue.

Question 2

Name the two key enzymes involved in swapping carbons between sugars in the carbon shuffling reactions of stage 3 of the Calvin cycle, and describe the differences in their
reactions.

Accepted Answer

Transaldolase and transketolase. Transal

Question 3

Ribulose bisphosphate carboxylase (rubisco)

Accepted Answer

A)  is the most abundant enzyme in the biosphere, comprising as much as 50% of plant cell protein. 
B)  catalyzes the reaction of C5 molecule and CO2 with a C6 sugar product. 
C)  is located in the thylakoid lumen. 
D)  requires NADPH and ATP to fix CO2. 
A)  is the most abundant enzyme in the biosphere, comprising as much as 50% of plant cell protein. 
B)  catalyzes the reaction of C5 molecule and CO2 with a C6 sugar product. 
C)  is located in the thylakoid lumen. 
D)  requires NADPH and ATP to fix CO2.

Question 4

C4 plants are thought to be more efficient than C3 plants because they

Accepted Answer

A)  make larger sugar molecules from CO2. 
B)  can concentrate the CO2 in chloroplasts and therefore minimize side reactions with O2. 
C)  can produce sugar molecules at night in addition to during the day. 
D)  can live in dry climates. 
A)  make larger sugar molecules from CO2. 
B)  can concentrate the CO2 in chloroplasts and therefore minimize side reactions with O2. 
C)  can produce sugar molecules at night in addition to during the day. 
D)  can live in dry climates.

Question 5

What is the overall reaction for the Calvin cycle, or dark reactions?

Accepted Answer

A)  2 H2O + 2 NADP+ + 3 ADP + 3 Pi $\rightarrow$O2 + 2 NADPH + 3 ATP 
B)  3 CO2 + 6 NADPH + 9 ATP + 6 H2O $\rightarrow$Glyceraldehyde-3-phosphate + 6 NADP+ + 9 ADP + 9 Pi 
C)  6 CO2 + 6 NADPH + 12 ATP $\rightarrow$ Glucose + NADP+ + ADP + Pi 
D)  Glucose $\rightarrow$ 9 ATP + 12 NADPH + 6 CO2 + 6 H2O 
A)  2 H2O + 2 NADP+ + 3 ADP + 3 Pi $\rightarrow$O2 + 2 NADPH + 3 ATP 
B)  3 CO2 + 6 NADPH + 9 ATP + 6 H2O $\rightarrow$Glyceraldehyde-3-phosphate + 6 NADP+ + 9 ADP + 9 Pi 
C)  6 CO2 + 6 NADPH + 12 ATP $\rightarrow$ Glucose + NADP+ + ADP + Pi 
D)  Glucose $\rightarrow$ 9 ATP + 12 NADPH + 6 CO2 + 6 H2O

Question 6

Briefly describe the three stages of the Calvin cycle.

Accepted Answer

(1) The enzyme rubisco catalyzes the fix

Question 7

The __________ is driven directly by photons from the sun in photosynthesis light reactions.

Accepted Answer

A)  pumping of protons 
B)  synthesis of ATP 
C)  transfer of electrons 
D)  synthesis of glucose 
A)  pumping of protons 
B)  synthesis of ATP 
C)  transfer of electrons 
D)  synthesis of glucose

Question 8

Explain how CAM plants cooperate to accomplish the delivery of CO2 to the Calvin cycle.

Accepted Answer

CO₂ is absorbed at night, when it is cool

Question 9

What is the main difference between C4 and CAM plants?

Accepted Answer

CAM plants open up their stomata at nigh

Question 10

List the three possible fates of an electron in an excited state chlorophyll molecule.

Accepted Answer

See Figure 12.9 below. (1) Electron tran

Question 11

Which is the orange pigment commonly found in plant's light harvesting complexes?

Accepted Answer

A)  "chlorophyll" 
B)  "phycocyanobilin" 
C)  "porphyrin" 
D)  "$\beta$-carotene" 
A)  "chlorophyll" 
B)  "phycocyanobilin" 
C)  "porphyrin" 
D)  "$\beta$-carotene"

Question 12

List the four proteins/enzymes and the one molecule involved in the electron transfers in the photosynthetic Z scheme, and show their positions in the "Z" shape.

Accepted Answer

(1) Photosystem 1 (PSI), (2) photosystem

Question 13

The glyoxylate cycle reaction shown below is catalyzed by which enzyme class?

Accepted Answer

A)  lyase 
B)  hydrolase 
C)  transferase 
D)  oxidoreductase 
A)  lyase 
B)  hydrolase 
C)  transferase 
D)  oxidoreductase

Question 14

What is the cellular location of the plant glyoxylate cycle?

Accepted Answer

A)  chloroplast stroma 
B)  cytoplasm 
C)  mitochondria 
D)  glyoxysome 
A)  chloroplast stroma 
B)  cytoplasm 
C)  mitochondria 
D)  glyoxysome

Question 15

Draw the path of electrons in the cyclic photophosphorylation pathway showing the main enzymes and electron carriers involved and demonstrating its cyclic nature.

Accepted Answer

See Figure 12.38 below. photos

Question 16

What is the process depicted below, where plants react with O2?

Accepted Answer

A)  photorespiration 
B)  photosynthesis 
C)  photogeneration 
D)  photoglycolate pathway 
A)  photorespiration 
B)  photosynthesis 
C)  photogeneration 
D)  photoglycolate pathway

Question 17

Draw a picture of the chloroplast and show the location of and direction in which protons are pumped during photosynthetic light reactions.

Accepted Answer

See Figure 12.7 belo

Question 18

Approximately how many ATP are synthesized per O2 molecule generated in photosynthesis light reactions?

Accepted Answer

A)  3 
B)  4 
C)  8 
D)  12 
A)  3 
B)  4 
C)  8 
D)  12

Question 19

List the five steps of photosynthesis, whereby solar energy is converted into chemical energy.

Accepted Answer

(1) Photons oxidize chlorophyll, which i

Question 20

Under what condition(s) do the wasteful side reaction of O2 with rubisco become significant?

Accepted Answer

A)  higher levels of CO2 than O2 
B)  at night 
C)  increased temperature and intense light 
D)  increased rubisco concentrations 
A)  higher levels of CO2 than O2 
B)  at night 
C)  increased temperature and intense light 
D)  increased rubisco concentrations

Exam 12: Photosynthesis

The third stage of the three-stage Calvin cycle

Name the two key enzymes involved in swapping carbons between sugars in the carbon shuffling reactions of stage 3 of the Calvin cycle, and describe the differences in their reactions.

Ribulose bisphosphate carboxylase (rubisco)

C4 plants are thought to be more efficient than C3 plants because they

What is the overall reaction for the Calvin cycle, or dark reactions?

Briefly describe the three stages of the Calvin cycle.

The __________ is driven directly by photons from the sun in photosynthesis light reactions.

Explain how CAM plants cooperate to accomplish the delivery of CO2 to the Calvin cycle.

What is the main difference between C4 and CAM plants?

List the three possible fates of an electron in an excited state chlorophyll molecule.

Which is the orange pigment commonly found in plant's light harvesting complexes?

List the four proteins/enzymes and the one molecule involved in the electron transfers in the photosynthetic Z scheme, and show their positions in the "Z" shape.

The glyoxylate cycle reaction shown below is catalyzed by which enzyme class?

What is the cellular location of the plant glyoxylate cycle?

Draw the path of electrons in the cyclic photophosphorylation pathway showing the main enzymes and electron carriers involved and demonstrating its cyclic nature.

What is the process depicted below, where plants react with O2?

Draw a picture of the chloroplast and show the location of and direction in which protons are pumped during photosynthetic light reactions.

Approximately how many ATP are synthesized per O2 molecule generated in photosynthesis light reactions?

List the five steps of photosynthesis, whereby solar energy is converted into chemical energy.

Under what condition(s) do the wasteful side reaction of O2 with rubisco become significant?

Principles of Biochemistry

Physical Biochemistry: Energy Conversion, Water, and Membranes

Nucleic Acid Structure and Function

Protein Structure

Methods in Protein Biochemistry

Protein Function

Enzyme Mechanisms

Cell Signaling Systems

Glycolysis: a Paradigm of Metabolic Regulation

The Citrate Cycle

Oxidative Phosphorylation

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Metabolic Integration

DNA Replication, Repair, and Recombination

RNA Synthesis, Processing, and Gene Silencing

Protein Synthesis, Posttranslational Modification, and Transport

Gene Regulation

Filters

C₄ plants are thought to be more efficient than C₃ plants because they

Explain how CAM plants cooperate to accomplish the delivery of CO₂ to the Calvin cycle.

What is the main difference between C₄ and CAM plants?

What is the process depicted below, where plants react with O₂?

Approximately how many ATP are synthesized per O₂ molecule generated in photosynthesis light reactions?

Under what condition(s) do the wasteful side reaction of O₂ with rubisco become significant?