Q.15 Match the enzymes in Group I with the corresponding substrate in Group II
Group I                                                          Group II
(P) Amylase                                                  (1) Protein
(Q) Pepsin                                                     (2) Fat
(R) Lipase                                                      (3) RNA
(S) Ribozyme                                                (4) Starch

(A) P-2, Q-3, R-1, S-4
(B) P-4, Q-1, R-2, S-3
(C) P-3, Q-1, R-4, S-2
(D) P-4, Q-2, R-3, S-1

Amylase breaks down starch, pepsin digests proteins, lipase hydrolyzes fats, and ribozyme cleaves RNA. The correct matching is option (B): P-4 (Starch), Q-1 (Protein), R-2 (Fat), S-3 (RNA).

Enzyme-Substrate Matches

Amylase (P) acts on starch (4), initiating carbohydrate digestion in saliva and pancreas by hydrolyzing α-1,4-glucosidic bonds.
Pepsin (Q) targets proteins (1), functioning as a stomach protease that cleaves peptide bonds in acidic conditions.
Lipase (R) hydrolyzes fats (2) or triglycerides into fatty acids and glycerol, aiding lipid digestion.
Ribozyme (S) catalyzes RNA (3) cleavage, as seen in self-splicing introns and viroids.

Option Analysis

• (A) P-2, Q-3, R-1, S-4: Incorrect; amylase does not act on fat, pepsin skips RNA, lipase avoids protein, ribozyme ignores starch.

• (B) P-4, Q-1, R-2, S-3: Correct; matches confirmed biological specificities for each enzyme.

• (C) P-3, Q-1, R-4, S-2: Wrong; amylase and lipase mismatched to RNA/starch, ribozyme not for fat.

• (D) P-4, Q-2, R-3, S-1: Invalid; pepsin and lipase swapped incorrectly, ribozyme not protein-specific.

In CSIR NET Life Sciences preparation, mastering enzyme-substrate specificity is key for questions on digestion, molecular biology, and biotechnology. This guide solves the classic matching question on amylase, pepsin, lipase, and ribozyme substrates, vital for topics like enzyme kinetics and catalytic RNA.

Correct Pairings Explained

• Amylase (P) – Starch (4): Salivary and pancreatic amylase hydrolyzes starch into maltose, optimal at pH 6.9-7.0 with calcium.

• Pepsin (Q) – Protein (1): Gastric enzyme activates from pepsinogen, cleaving proteins at aromatic residues in low pH.

• Lipase (R) – Fat (2): Pancreatic lipase breaks triglycerides, aided by bile for emulsification.

• Ribozyme (S) – RNA (3): RNA-based catalyst, like hammerhead ribozyme, performs self-cleavage or ligation.

Why Option B Wins for CSIR NET

Option B perfectly aligns: P-4, Q-1, R-2, S-3. Others fail specificity—e.g., lipase on protein (A) ignores lipid focus. Use this for quick recall in exams.