Question

Match List-I with List-II

List-I (Name of the component) & List-II (Vitamin/Coenzyme)
(A) Pantothenic acid & (II) Coenzyme A
(B) Para-Amino Benzoic Acid (PABA) & (III) Folic acid
(C) Ribose & (I) NAD
(D) Pentanoic acid & (IV) Lipoic acid

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

Hint:

To remember this:
- Pantothenate is the direct precursor of Coenzyme A.
- PABA is a key structural block of Folic acid (sulfonamide antibiotics work by acting as structural analogs of PABA to inhibit folic acid synthesis).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Many critical biological coenzymes are constructed from basic chemical components, including vitamins, organic acids, and pentose sugars.

Step 2: Detailed Explanation:
Let us pair each chemical component with its corresponding coenzyme or vitamin:
- (A) Pantothenic acid $\rightarrow$ (II) Coenzyme A:
Pantothenic acid (Vitamin B5) is a water-soluble vitamin.
It is chemically joined to ADP and beta-mercaptoethylamine to synthesize Coenzyme A (CoA), which is an essential acyl carrier in metabolism.
- (B) Para-Amino Benzoic Acid (PABA) $\rightarrow$ (III) Folic acid:
Folic acid (Vitamin B9) is composed of three structural units: a pteridine ring, glutamic acid, and para-aminobenzoic acid (PABA).
PABA serves as an essential intermediate block during the biosynthesis of folic acid.
- (C) Ribose $\rightarrow$ (I) NAD:
Nicotinamide Adenine Dinucleotide (NAD) is a major electron carrier.
It contains two ribose sugars—one linked to nicotinamide and the other linked to adenine—forming its core dinucleotide structure.
- (D) Pentanoic acid $\rightarrow$ (IV) Lipoic acid:
Lipoic acid consists of a five-membered disulfide-containing ring (dithiolane) attached to a 5-carbon carboxylic acid chain (pentanoic acid).
This chemical side chain allows it to covalently attach to a lysine residue of enzyme complexes.
This gives the matching sequence: (A)-(II), (B)-(III), (C)-(I), (D)-(IV).

Step 3: Final Answer:
The correct matching sequence is (A) - (II), (B) - (III), (C) - (I), (D) - (IV).