Is nutrition a necessity for an

Yes, nutrition is a must for an organism because of the following reasons :

Importance of Nutrition/Food

1. Food provides energy: Energy is required by the body all the time, whether asleep, taking rest or doing work. When the body is not doing any apparent work, energy is still being consumed in maintaining order. Further, biosynthetic activities continue for replacing materials being consumed or degraded. A number of other activities are going on all the time. Heart is always beating. Breathing movements never stop. Food eaten by a person has to be digested and absorbed. Excretory products are being produced.
2. Body Structure: All body components are built up of materials obtained from food.
3. Food is used in building protoplasm. More protoplasm is required for formation and enlargement of cells that take part in growth of the organism.
4. Food provides materials for replacement and repair of worn out or damaged structures.
5. Hormones and enzymes are formed from ingredients of food. They regulate metabolism and body functions.                                                                ‘
6. Defence system of the body is formed from raw materials got- from food.
7. Food provides materials to form reproductive structures.