Question

Which of the following processes in the Calvin cycle require the expenditure of ATP?

A: carbon fixation
B: sugar production
C: regeneration of RuBP
D: A and B
E: B and C
F: A, B, and C

Answer 1

All processes A, B, and C in the Calvin cycle require the expenditure of ATP. These include carbon fixation, sugar production from G3P, and the regeneration of RuBP.

Step-by-step explanation:

The question is asking which processes in the Calvin cycle require the use of ATP. The correct answer is F: A, B, and C, which means that ATP is expended in carbon fixation, sugar production, and the regeneration of RuBP. During the Calvin cycle, ATP is used in the reduction stage to help convert 3-phosphoglycerate into glyceraldehyde-3-phosphate (G3P) and then sugar production from G3P. Additionally, ATP is utilized during the regeneration of RuBP, where 5 G3P molecules (with a total of 15 carbon atoms) are converted into 3 RuBP molecules (also with a total of 15 carbon atoms).