Define Nutrition

Q: Define nutrition 

Answer: Nutrition is a physiological and biochemical process of taking food responsible for carrying out different body functions. It is an essential process needed for the survival of living organisms. It nourishes the body in the form of proteins, vitamins, carbohydrates, fat, water, fiber, and minerals. 

Generally, there are two types of nutrition, i.e., autotrophic and heterotrophic. The term autotrophic is made out of the auto, which means self, and trophic, meaning nutrition. When living organisms prepare their food, for instance, the green plants, they are called autotrophs, and the nutrition produced by them is known as autotrophic nutrition. All green plants have an autotrophic mode of nutrition and prepare their food through photosynthesis. Examples of autotrophs are- blue-green algae plants and bacteria like cyanobacteria. 

Heterotrophic nutrition is another nutrition type in which a living organism depends on other entities for its food, such as animals and non-photosynthetic plants. However, these heterotrophs are secondary and tertiary consumers of a food chain process. There are three heterotrophic nutrition types: Holozoic nutrition, Saprophytic nutrition, and parasitic nutrition. Holozoic nutrition includes the ingestion and internal processing of liquid and solid in an organism. In this process, an organism consumes the whole food. Saprophytic nutrition occurs when organisms feed decayed and dead organisms for energy. In this way, they also help the ecosystem keep the environment clean. Examples of saprophytes are some bacteria types and fungi. Parasitic nutrition occurs when a living organism lives on other organisms and derives its nutrition at the expense of its host.