Question

Given below are two statements:
Statement I: ATP synthase produces ATP as protons diffuse back through it from the lumen into the stroma.
Statement II: Malate and aspartate are carboxylation products of the C3 cycle.
In light of the above statements, choose the most appropriate answer from the options given below:

• A. Both Statement I and Statement II are true
• B. Both Statement I and Statement II are false
• C. Statement I is correct but Statement II is false
• D. Statement I is incorrect but Statement II is true

Hint:

Photosynthesis pathways:
- C3 cycle (Calvin): First product = 3-PGA.
- C4 cycle: First product = Malate or Aspartate.
- CAM: Malate is stored at night.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
This question tests knowledge of photosynthesis and the Calvin cycle.

Step 2: Detailed Explanation:
Statement I:
During photosynthesis, protons (H+) accumulate in the thylakoid lumen.
As they diffuse back into the stroma through ATP synthase, ATP is produced.
This statement is true.
Statement II:
Malate and aspartate are products of the C4 cycle (Hatch-Slack pathway), not the C3 cycle (Calvin cycle).
In the C3 cycle, the first carboxylation product is 3-phosphoglycerate (3-PGA).
This statement is false.
Thus, Statement I is correct, but Statement II is false.

Step 3: Final Answer:
Thus, Statement I is correct but Statement II is false, which corresponds to option (C).
[0.5cm]