nutrition

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Nutrition is the process of intake of food,its digestion, absorption and distribution to diffrent part of body

Food an organic substance, is used by living beings to remain alive. It is the source of energy and provide raw material for the synthesis of body constituents. When consumed, food passes through biochemical changes and finally the nutrients are absorbed by or body. The main classification of types of food:

Carbohydrate and fat (energy giving)

Protein and mineral salt (body building)

Vitamin and mineral (regulating food)

The simplest form of food is glucose, this does not need and any further breakdown and when consumed gives instant energy.

Mode of nutrition (on the basis of taking of food)

1.       Autotrophic nutrition

2.       Heterotrophic nutrition

Autotrophic nutrition (Gk. Auto-self, troph-nutrition) they use raw material from environment to manufacture their own food. Autotrophs are divided in two category on the basis of the way they manufacture their food

a.       Photo-autotrophic (photosynthesis)

b.      Chemo-autotrophic(chemosynthesis)

A.      photosynthesis is shown by green plants, protists and photosynthetic bacteria. These contain chlorophyll, a green pigment which help them sysnthesize food in presence of simple raw material like CO₂, H₂O in presence of sunlight.

B.      In chemosynthesis energy stored in food is obtained from some chemical, they require only organic material from atmosphere, carbon is obtained from CO₂._.  e.g.; Hydrogen  bacteria, iron bacteria, nitrifying bacteria.
 
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