Biology · BIOMOLECULES
हिन्दीStarch gives a blue colour with iodine (\( \text{I}_2 \)), but cellulose does not give this test. What is the precise structural basis for this difference?
Correct answer · Option 1
Starch forms helical secondary structures that can trap \( \text{I}_2 \) molecules in the helical portion, whereas cellulose does not contain complex helices.
Explanation
Starch forms helical secondary structures capable of holding \( \text{I}_2 \) within the helix, producing a blue colour. Cellulose lacks these helices and cannot hold \( \text{I}_2 \).