Question

Assertion A: Inhibition of succinate dehydrogenase by malonate represents competitive inhibition.
Reason R: Malonate and succinate bind at different sites of the enzyme.

• A. Both A and R are correct and R is the correct explanation of A
• B. Both A and R are correct but R is NOT the correct explanation of A
• C. A is correct but R is not correct
• D. A is not correct but R is correct

Hint:

"Competitive" means they compete for the same "parking spot" (Active Site).

Answer 1

The Correct Option is C

Step 1: Concept
Competitive inhibition occurs when an inhibitor resembles the substrate and competes for the same active site.

Step 2: Meaning
Malonate is a structural analog of succinate, the natural substrate for succinate dehydrogenase.

Step 3: Analysis
Assertion A is true: this is the classic example of competitive inhibition. Reason R is false: competitive inhibitors bind at the same active site, not different sites.

Step 4: Conclusion
Therefore, A is correct but R is incorrect. Final Answer: (C)