All those process in which food is taken from external environment and these food materials release energy which is used for growth are called Nutrition

Types Of Nutrition:

Autotrophic Nutrition: Autotrophic nutrition is a process in which organisms prepare their food from the simple inorganic substances like water, minerals and carbon-dioxide in the presence of sunlight.

Heterotrophic Nutrition: Heterotrophic nutrition is the process in which organism depends upon other organism for their survival and growth.

Nutrition in plants

On the basis of their nutrition plants are categorized into two types:

Autotrophic Plants: Autotrophic plants are those plants which prepare their own food. All green plants are autotrophic plants they prepare their food by the process called photosynthesis.

Heterotrophic Plants: Those plants which depends on any other living or dead organic materials for their food are called heterotrophic plants.

Types of Heterotrophic Plants:

Heterotrophic plants further classified into four types:

  1. Parasitic Plants: In this type of plants nutrition of one organism depends upon another organism for getting food . The organism which depends is known asparasite”and the organism on which it depends is known as “Host”.
  2. Saprophytic Plants: This type of plants depends on dead and decaying material for food.
  3. Symbiotic Plants: When two plants live together and spend their life with each other they are called Symbiotic plants.
  4. Insectivorous: Plants which depends upon insects for their food were come under this category.


Photosynthesis is a metabolic process by which all green plant make their own food. In this process carbon-dioxide and water combine in the presence of sunlight and chlorophyll to form carbohydrates and oxygen released as a byproduct.

Chemical Reaction involved in photosynthesis:

Nutrition in Animals

Heterotrophic nutrition takes place in animals. Animal require energy for their growth, multiplication and other biological activities. They obtain energy from food which they get from other organism. Three types of nutrition occur in animals:

-Holozoic: In this type of nutrition solid food is ingested by mouth and then it is digested followed by the process of absorption and assimilation.

-Saprozoic: When organism get food from dead or decaying organic material they are called saprozoic. Example- insects.

-Parasitic: When organisms depend upon other organisms for their food for example mosquitoes.