Difine ingestions

Nutrition in complex animals involves following steps:

• Ingestion
• Digestion
• Absorption
• Assimilation
• Egestion

Ingestion: The intake of food is called ingestion. Method of ingestion, i.e. taking of food, varies from one animal to another.

Digestion: The process of breaking down of complex component of food into simpler substances is called digestion. The process of digestion is different in human, grass eating animals, amoeba, etc.

Absorption: The process of passing of digested food into blood vessels in the intestine is called the absorption.

Assimilation: The conversion of absorbed food in complex substances such as proteins and vitamins required by body is called assimilation. In other words, assimilation is the conversion of absorbed food (nutrients) into living tissues. Through the process of assimilation our cells are supplied with oxygen and nutrients.

Egestion: Removal of waste materials from the body is called egestion. The faecal matter is removed through the **** from time-to-time. Since the waste of food left after digestion is also called faeces, hence the process of egestion is also known as defecation.