Chapter 10.4

Question 1

What are the reactants of the Calvin cycle?

Answer 1

CO2, NADPH, ATP

Question 2

What are the products of the Calvin cycle?

Answer 2

Glucose, NADP+, ADP

Question 3

Why is the Calvin cycle similar to the Citric Acid cycle?

Answer 3

The starting material is regenerated after some molecules enter and exit the cycle.

Question 4

What does the Calvin cycle do?

Answer 4

It builds sugar from smaller molecules by using ATP and NADPH.

Question 5

Glyceraldehyde 3-Phosphate (G3P)

Answer 5

A three-carbon sugar that is produced directly from the Calvin cycle.

Question 6

How does one molecule of G3P get synthesized?

Answer 6

The Calvin cycle occurs three times, fixing three molecules of CO2 together.

Question 7

What are the three phases of the Calvin cycle?

Answer 7

1. Carbon Fixation
2. Reduction
3. Regeneration of the CO2 acceptor

Question 8

What happens during carbon fixation?

Answer 8

The enzyme, Rubisco, catalyzes the first step, “fixing” CO2 to Ruibulose Biphosphate (RuBP).

3RuBP + 3[CO2] -> 6[3-phosphoglycerate]

Question 9

Ruibulose Biphosphate (RuBP)

Answer 9

The acceptor molecule for CO2.

Question 10

Rubisco

Answer 10

The enzyme that catalyzes the first reaction in the Calvin cycle – The most abundant protein in the world.

Question 11

What happens during reduction?

Answer 11

Carbon dioxide is reduced by adding H(ydrogen).

6[3-phosphoglycerate] + 3[ATP] + 6[NADPH] -> 6[G3P]

Question 12

What happens during regneration of RuBP?

Answer 12

G3P molecules and ATP molecules are used to regenerate RuBP to continue the cycle.

5[G3P] + 3[ATP] -> 3[RuBP]