Distinguish between autotrophic and heterotrophic nutrition.
Autotrophic Nutrition :

1. It is the nutrition in which organisms manufacture their own food from CO
2and H2O. It is of two types photoautotrophic and chemoautotrophic. 

Heterotrophic Nutrition :

1. In this mode of nutrition the organisms cannot manufacture their own food and feed upon high energy organic molecules. It is of four types holozoic, saprozoic, parasitic and symbiotic nutrition.