Question

Zinc is essential for the function of

• A. carboxypeptidase A.
• B. chlorophyll a.
• C. myoglobin.
• D. vitamin \(B_{12}\).

Hint:

Zinc is an essential trace element and is involved in numerous enzyme catalysis, particularly those related to protein digestion and the immune system.

Answer 1

The Correct Option is A

Zinc plays a crucial role as a cofactor in various enzymes. Carboxypeptidase A is a zinc-dependent enzyme that catalyzes the hydrolysis of peptide bonds at the carboxyl end of proteins. Zinc is involved in the enzyme's active site, facilitating the cleavage of peptide bonds. This makes statement (A) correct.
- (B): Chlorophyll a is a magnesium-containing pigment in plants and plays a central role in photosynthesis. Zinc is not involved in the function of chlorophyll a. Hence, statement (B) is incorrect.
- (C): Myoglobin is an oxygen-binding protein found in muscles and does not require zinc for its function. Therefore, statement (C) is incorrect.
- (D): Vitamin \(B_{12}\), which contains the element cobalt at its core, does not require zinc for its activity. Thus, statement (D) is incorrect.
Thus, the correct answer is (A).