Question

Which is not true regarding non-cyclic electron transport:

• A. Both PS-I and PS-II are involved
• B. Requires 680 nm or less than 680 nm light
• C. Happens on the grana lamellae
• D. ATP and NADPH + H are synthesized

Hint:

Non-cyclic = Z-scheme = Both PSII and PSI working together.

Answer 1

The Correct Option is C

Step 1: The task.
We have to spot the statement about non-cyclic electron transport that is NOT true.

Step 2: What is non-cyclic flow.
This is the Z-scheme. Electrons travel from water through Photosystem II and then Photosystem I, and finally to NADP. So both PS-I and PS-II take part. That statement is true.

Step 3: Light needed.
PS-II uses light of about 680 nm or shorter to split water. So saying it needs 680 nm or less light is also true.

Step 4: The products.
Non-cyclic flow makes both ATP and NADPH + H, since electrons end up reducing NADP. That statement is true as well.

Step 5: The location, the odd one out.
Non-cyclic transport is not limited to the grana lamellae. PS-I is also present in the stroma lamellae. So the claim that it happens on the grana lamellae alone is the wrong, or not true, statement here.

Step 6: Conclusion.
Therefore the correct answer is "Happens on the grana lamellae". \[ \boxed{\text{Happens on the grana lamellae}} \]