The force which does not stabilise the tertiary structure of proteins is
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → sulphate bonds
Option (1) hydrogen bonds — Stabilises the tertiary structure. Hydrogen bonds between polar groups help hold the folded chain in shape.
Option (2) disulphide linkages — Stabilises the tertiary structure. Covalent –S–S– bridges between cysteine side chains lock parts of the chain together.
Option (3) van der Waals forces — Stabilises the tertiary structure. Weak attractions between non-polar side chains also stabilise the folded structure.
Option (4) sulphate bonds — Does not stabilise it. There is no “sulphate bond” in proteins; the sulphur of cysteine forms disulphide (–S–S–) bridges, not sulphate links.
NCERT (2026-27 edition):
Tertiary Structure of Proteins
