What are vitamins ? Why they are called essential nutrients ? What is their role in the human body ?

Explanation

1) Vitamins are organic substances:
2) They are micro -nutrients required in small quantities.
3) By themselves vitamins cannot generate any energy or carryout any chemical reaction.
4) In the body, vitamins combine with some of the enzymes and make the enzymes active.
5) In the absence of vitamins, enzymes become inactive and cannot catalyse the reactions.
6) Vitamins are normally present in all types of natural foods -milk, meat, fruits and . vegetables.
7) Vitamins are of two types : 1. Water soluble vitamins eg : B complex and Vitamin C and 2. Fat soluble vitamins eg: A, D, E and K.