Question

Which of the following statements are correct?
(i) Chitin, a complex or heteropolysaccharide occuring in exoskeleton consists of NAG.
(ii) Glucosamine and N-acetyl glucosamine are modified sugar.
(iii) Cellulose shows blue colour when treated with $I_2$.
(iv) Starch in plants and glycogen in animals are store houses of energy.
(v) Right end of polysaccharide is called reducing end while left end is called non-reducing end.

• A. (i), (ii) and (iii)
• B. (iii), (iv) and (v)
• C. All except (iii)
• D. All except (v)

Answer 1

Answer: (C)

Starch can hold iodine $\left( I _2\right)$ molecules in its helical secondary structure but cellulose being non helical, cannot hold $I_2$. Thus, cellulose does not shows blue colour when treated with $I _2$.