There are mainly two modes of nutrition:

(i) Autotrophic Nutrition

(ii) Heterotrophic Nutrition

(i) Autotrophic Nutrition: Autotrophic nutrition is that mode of nutrition in which organisms prepare their own food from inorganic substances like carbon dioxide and water in the presence of sunlight and chlorophyll. All green plants obtain their food by autotrophic nutrition.

(ii) Heterotrophic nutrition: Heterotrophic nutrition is that mode of nutrition in which organisms cannot prepare their own food from inorganic substances like carbon dioxide and water and depend on other organisms for their food. All the animals, fungi, and bacteria have heterotrophic mode of nutrition.