Question
Biology Question on Calvin cycle
How many molecules of ATP and NADPH are required for every molecule of CO2 fixed in the Calvin cycle?
A
2 molecules of ATP and 3 molecules of NADPH
B
2 molecules of ATP and 2 molecules of NADPH
C
3 molecules of ATP and 3 molecules of NADPH
D
3 molecules of ATP and 2 molecules of NADPH
Answer
3 molecules of ATP and 2 molecules of NADPH
Explanation
Solution
In the Calvin cycle, for every molecule of CO fixed, 3 molecules of ATP and 2 molecules of NADPH are required to convert 3-phosphoglycerate (3-PGA) into G3P (Glyceraldehyde-3-phosphate).
- ATP provides the energy necessary for the phosphorylation steps, while NADPH provides the reducing power for the reduction steps.