DARK REACTIONS

What is the primary product of the Calvin cycle?

• a) Oxygen

• b) Water

• c) Glucose

• d) Carbon dioxide

• A

• B

• C

• D

Why is the Calvin cycle considered a light-independent reaction, even though it relies on light energy?

• a) It occurs in the dark.

• b) It doesn't directly use sunlight.

• c) It uses products generated by the light-dependent reactions.

• d) It can occur in the absence of chlorophyll.

• A

• B

• C

• D

What is the initial molecule that combines with CO₂ in the Calvin cycle?

• a) Glucose

• b) RuBP

• c) ATP

• d) NADPH

• A

• B

• C

• D

What enzyme catalyzes the first step of the Calvin cycle?

a) Rubisco

b) ATP synthase

c) NADP reductase

d) Photosystem I

• A

• B

• C

• D

How many molecules of CO₂ are needed to produce one molecule of glucose?

What is the role of ATP and NADPH in the Calvin cycle?

a) To provide energy and reducing power.

b) To capture sunlight energy.

c) To transport electrons.

d) To break down glucose.

• A

• B

• C

• D

What is the primary adaptation of CAM plants to minimize water loss?

a) Storing CO₂ in organic acids.

b) Opening stomata at night.

c) Separating CO₂ fixation and the Calvin cycle spatially.

d) Using a different enzyme for CO₂ fixation.

• A

• B

• C

• D

Why is the Calvin cycle also known as the reductive pentose phosphate cycle?

a) It involves the reduction of phosphate groups.

b) It involves the reduction of pentose sugars.

c) It involves the phosphorylation of pentose sugars.

d) It involves the oxidation of pentose sugars.

• A

• B

• C

• D

What is the primary adaptation of C4 plants to minimize photorespiration?

a) Storing CO₂ in organic acids.

b) Opening stomata at night.

c) Separating CO₂ fixation and the Calvin cycle spatially.

d) Using a different enzyme for CO₂ fixation.

• A

• B

• C

• D

What is the role of RuBP in the Calvin cycle?

a) To provide energy for the cycle.

b) To accept CO₂ and initiate the cycle.

c) To transport electrons.

d) To store glucose.

• A

• B

• C

• D