Question

(i) Deficiency of which vitamin causes the following diseases:
(1) Scurvy
(2) Night blindness
(ii) Write two differences between globular and fibrous proteins.

Answer 1

(i) (1) Scurvy is caused by the deficiency of vitamin C (ascorbic acid). Scurvy is characterized by bleeding into the skin and deeper tissues, swollen and bleeding gums and fragile bones.

(2) Night blindness is caused by the deficiency of vitamin A (Axerophytol or retinol).
(ii) Differences between globular and fibrous proteins are:

Globular proteins	Fibrous proteins
Protein molecule is folded into compact units which often acquire spheroidal shape.	They have thread like molecules which lie side by side to form fibres. The various molecules are held together by hydrogen bonds.
They are water soluble.	They are water insoluble.