JEE Main · 2022 · 29 Jun 2022 · Shift 2 · Biomolecules

The structure of protein that is unaffected by heating is :

(A)secondary structure
(B)tertiary structure
(C)primary structure✓ Correct
(D)quaternary structure

Answer: (C)

Solution

The primary structure of a protein refers to the sequence of amino acids linked by peptide bonds. This covalent bond structure is stable and unaffected by heating or mild physical/chemical changes. In contrast, secondary (α-helix, β-sheet), tertiary (3D folding), and quaternary (multi-subunit assembly) structures are maintained by weaker interactions like hydrogen bonds, ionic interactions, and hydrophobic forces, which are disrupted by heating (denaturation). Therefore, only the primary structure remains intact upon heating.

JEE Main · 2022 · 29 Jun 2022 · Shift 2 · Single correct option

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