Question

Identify the mismatched pair

• A. NADP reductase enzyme $\rightarrow$ Stroma lamellae
• B. PEP case $\rightarrow$ Mesophyll cell
• C. RuBisCO $\rightarrow$ Bundle sheath cell
• D. ATP synthetase enzyme $\rightarrow$ Chloroplast

Hint:

{Stroma Lamellae} = Only PS I = Cyclic Photophosphorylation = No NADPH formed (No NADP reductase).

Answer 1

The Correct Option is A

Step 1: Analyze Enzyme Locations:

• (A) NADP reductase: This enzyme is located on the stroma side of the thylakoid membrane. However, it is associated with Photosystem I (PS I). According to standard texts (e.g., NCERT), stroma lamellae membranes lack PS II and NADP reductase. This is why only cyclic photophosphorylation occurs there. Thus, placing it in stroma lamellae is a mismatch.
• (B) PEPcase: Found in the cytosol of Mesophyll cells in C$_4$ plants. Correct.
• (C) RuBisCO: Found in the Bundle sheath cells of C$_4$ plants (and mesophyll of C$_3$). Correct.
• (D) ATP synthetase: Found in the thylakoid membrane of the Chloroplast. Correct.

Step 2: Conclusion:
Option (A) is the mismatched pair because the enzyme is absent in stroma lamellae.