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GATE 2025 BT – Question 24

General Biology · Biochemistry: Biomolecules, biological membranes, channels and pumps, molecular motors, action potential and transport · 1 mark · Multiple select

Which of the following show(s) optical activity at 100 mM concentration in water?

  1. Solution of NaCl
  2. Solution of D-Glucose
  3. Solution of Glycine
  4. Solution of L-Proline

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Correct answer: (B) Solution of D-Glucose; (D) Solution of L-Proline

Explanation

Optical activity needs a chiral molecule. D-glucose and L-proline are chiral. Glycine has no chiral carbon (its alpha carbon carries two hydrogens), and NaCl is not a molecule with chirality.