Question

The main steps of nutrition in humans are --, --, --, --, and --.

Answer 1

Hint: Nutrition is the process of taking in food and converting it into energy and other vital nutrients required for life.

Complete Answer:
The five steps which occur in the process of nutrition in animals are Ingestion, Digestion, Absorption, Assimilation, Egestion.
- Ingestion is the process by which food is taken inside (through the mouth), then chewed and broken down by teeth. The food that is taken in is broken down and mixes with saliva and this is known as bolus.
- Digestion is the process in which the food (it contains large, insoluble molecules, broken down into small, water soluble molecules) is then digested by secretion of certain enzymes and it is then used by the cells for producing energy.
- Absorption is the process in which the digested food passes (throughout the intestinal wall,) into the bloodstream. Our body cells use up the energy produced from the digested food; and then help in the building up various body tissues.
- Assimilation is the process in which the digested food moves into the different cells of the body, for energy, growth and repair.
- Egestion is the process by which the undigested food is expelled out from the body through excretion. In the human body, kidneys help in purifying blood and removing metabolic wastes from it.

Note: Broadly, there are two modes of nutrition among all the living organisms - Autotrophic mode ; Heterotrophic mode. A balanced diet improves the overall health of an organism and reduces the possible health risks. It provides energy to the cells to perform their required cellular activities.