Question

Which of the following is NOT present in the inner mitochondrial membrane?

• A. NADH-Q reductase
• B. ATP synthase
• C. Q-cytochrome c reductase
• D. Glycophorine

Hint:

Membrane Locations: Inner Mitochondrial Membrane = Complexes I, II, III, IV, and V (ATP Synthase). Glycophorin = RBC Plasma Membrane.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The inner mitochondrial membrane contains respiratory chain complexes and ATP synthase, while glycophorin is an erythrocyte plasma membrane protein.

Step 2: Detailed Explanation:
Evaluating the membrane proteins:
1. NADH-Q Reductase (Complex I): Integral inner mitochondrial membrane complex.
2. Q-Cytochrome c Reductase (Complex III): Integral inner mitochondrial membrane complex.
3. ATP Synthase (Complex V): Inner mitochondrial membrane rotary catalyst.
4. Glycophorin (Glycophorin A): A heavily sialylated, single-pass transmembrane glycoprotein found exclusively in the plasma membrane of red blood cells (erythrocytes), functioning to prevent RBC aggregation.

Step 3: Final Answer:
Thus, Glycophorin is NOT present in the inner mitochondrial membrane, matching option (D).