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JEE Main · 2021 · 16 Mar 2021 · Shift 2 · Biomolecules

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The secondary structure of protein is stabilised by:
  1. (A)Peptide bond
  2. (B)Hydrogen bonding✓ Correct
  3. (C)Glycosidic bond
  4. (D)Van der waals forces

Answer: (B)

Solution

The secondary structure is the regular local folding of the polypeptide backbone into an -helix or a -pleated sheet. What holds that regularity is a repeating hydrogen bond between the carbonyl oxygen of one peptide unit and the amide hydrogen of another further along the chain. Peptide bonds fix the primary sequence rather than the fold, glycosidic bonds join sugars and have no place in a protein, and van der Waals forces matter chiefly in the tertiary packing. The secondary structure is stabilised by hydrogen bonding.

JEE Main · 2021 · 16 Mar 2021 · Shift 2 · Single correct option

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