Question

In the Calvin cycle, the ratio of trioses formed, net gain, and used to regenerate RUBP is:

• A. 2 : 3 : 2
• B. 10 : 2 : 6
• C. 6 : 1 : 5
• D. 5 : 1 : 6

Hint:

Remember that the Calvin cycle is a light-independent reaction in photosynthesis, primarily occurring in the chloroplast stroma.

Answer 1

The Correct Option is C

To solve the problem, we need to determine the ratio of trioses formed, net gain, and the amount used to regenerate RUBP in the Calvin cycle.

1. Understanding the Calvin Cycle:
In the Calvin cycle, carbon dioxide is fixed into a three-carbon compound (triose), which is used to regenerate RUBP (Ribulose Bisphosphate) and to form sugars. The cycle involves both the formation of trioses and their subsequent use to regenerate RUBP.

2. Analyzing the Ratios:
The typical ratios in the Calvin cycle are:
Triose formation: Three carbon compounds (trioses) are formed.
Net gain: The net gain refers to the number of trioses that contribute to the production of sugars or other compounds.
Used to regenerate RUBP: A portion of the trioses is used to regenerate RUBP so the cycle can continue. The standard ratio of these three components is generally 6:1:5.
This represents 6 molecules of trioses, 1 molecule of net gain, and 5 molecules used to regenerate RUBP.

3. Conclusion:
Based on the standard ratios in the Calvin cycle, the correct option is:

Final Answer:
The correct option is (C) 6:1:5.