The process of release of energy from the assimilated food is called respiration. Respiration is a complex process which involves two distinct phases as follows :
1. Breathing or external respiration : Breathing involves movement which brings the air into the lungs and expels the air containing more of carbon dioxide from the lungs to the outer environment. External respiration is a physical process.
2. Cellular or internal respiration : It takes place in the mitochondria of the cells to release energy in the form of ATP. It is a biochemical process.
1. Breathing or external respiration : Breathing involves movement which brings the air into the lungs and expels the air containing more of carbon dioxide from the lungs to the outer environment. External respiration is a physical process.
2. Cellular or internal respiration : It takes place in the mitochondria of the cells to release energy in the form of ATP. It is a biochemical process.
