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JEE Main · 2007 · 29 Apr 2007 · Offline · Biomolecules

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The secondary structure of a protein refers to
  1. (A)-helical backbone✓ Correct
  2. (B)hydrophobic interactions
  3. (C)sequence of -amino acids
  4. (D)fixed configuration of the polypeptide backbone

Answer: (A)

Solution

The secondary structure of a protein is the regular local folding of the polypeptide backbone held together by hydrogen bonds between backbone groups, the -helix being the classic example. The bare order of the amino acids is the primary structure, while the packing driven by hydrophobic contacts belongs to the tertiary level. So the secondary structure is identified with the -helical arrangement of the backbone.

JEE Main · 2007 · 29 Apr 2007 · Offline · Single correct option

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