ingestion : the process of taking in food through mouth opening
digestion: is the process of breakdown of food into simple form with the help of digestive juices made in the body
absorption: is the process by which food in the simple form passes into body fluids such as blood
assimilation: is the process of using absorbed nutrients by the body cells for producing energy and for the growth of the body
egestion: is the process of removing waste matter from the body.