Q41.Match List I with List II

List-I (Enzymes)
A. Histone acetyl transferase
B. Cyclin dependent kinase
C. α-antitrypsin
D. Topoisomerase

List-II (Function)
I. DNA replication
II. Chromatin remodeling
III. Cell cycle regulation
IV. Emphysema

Choose the correct answer from the options given below:

(A) A-IV, B-I, C-II, D-III
(B) A-IV, B-I, C-III, D-II
(C) A-II, B-III, C-IV, D-I
(D) A-III, B-IV, C-II, D-I

The correct answer is option (C): A-II, B-III, C-IV, D-I. This matching pairs each enzyme from List-I with its primary biological function from List-II, based on established roles in molecular biology and physiology.

Enzyme-Function Matches

• A. Histone acetyl transferase → II. Chromatin remodeling: This enzyme acetylates lysine residues on histones, neutralizing their positive charge to loosen chromatin structure and promote gene transcription access.

• B. Cyclin dependent kinase → III. Cell cycle regulation: These kinases, activated by cyclins, phosphorylate targets like Rb protein to drive cell cycle progression through phases like G1/S and G2/M.

• C. α-antitrypsin → IV. Emphysema: Its deficiency allows unchecked neutrophil elastase activity, leading to lung tissue destruction and panacinar emphysema.

• D. Topoisomerase → I. DNA replication: It relieves supercoiling ahead of the replication fork by introducing transient DNA breaks, enabling unwinding and fork progression.

Option Analysis

• (A) A-IV, B-I, C-II, D-III: Incorrect. Histone acetyl transferase does not cause emphysema (IV); that’s α-antitrypsin deficiency. Cyclin dependent kinase is not primarily for DNA replication (I).

• (B) A-IV, B-I, C-III, D-II: Incorrect. Mismatches A to IV (emphysema) and B to I (replication); cyclin dependent kinase regulates cell cycle, not replication directly.

• (C) A-II, B-III, C-IV, D-I: Correct, as detailed above.

• (D) A-III, B-IV, C-II, D-I: Incorrect. Histone acetyl transferase is not for cell cycle regulation (III); cyclin dependent kinase does not relate to emphysema (IV).

Histone acetyl transferase, Cyclin dependent kinase, α-antitrypsin, and Topoisomerase are key enzymes in match List I with List II questions common in biology exams like NEET. This guide breaks down their functions—chromatin remodeling, cell cycle regulation, emphysema link, and DNA replication—for perfect matching.

Core Matches in Detail

Histone acetyl transferase (HAT) acetylates histones to relax chromatin for transcription, directly enabling chromatin remodeling. Cyclin dependent kinase (CDK) complexes control progression through cell cycle checkpoints via phosphorylation. α-Antitrypsin deficiency causes emphysema by failing to inhibit elastase, destroying lung alveoli. Topoisomerase resolves DNA supercoils during replication fork movement.

Why Option (C) Wins

In match List I with List II enzymes functions, option (C) aligns A-II, B-III, C-IV, D-I perfectly. Other options swap roles, like assigning HAT to emphysema, which ignores its epigenetic role.

Master this for exams—focus on HAT’s acetylation, CDK’s checkpoints, antitrypsin’s protease inhibition, and topoisomerase’s topology relief.