What are vitamins ? How are they classified ?

(a) What are vitamin ? How are these classified. Name the vitamins whose deficiency causes. (i) rickets (ii) beri - beri (iii) night blindness. (c ) Give two difference between hormones and vitamins.

What are proteins ? How are they classified ? Give two functions of proteins.

What are silicates ? How are they classified?

What are ethers? How are they classified?

What are ketones? How are ketones classified?