The process in which air moves in and out of the lungs is known as breathing.
Process of breathing
The breathing mechanism involves two processes:
- Inspiration or inhalation
In the method of inspiration or inhalation, there would be a contraction of muscles attached to the ribs on the outer side which pulls out the ribs and results in the expansion of the chest cavity. Later, the diaphragm, contracts, moves downwards and expands the chest cavity resulting in the contraction of the abdominal muscles.
- Expiration or exhalation
The expiration or exhalation method is viewed once after the gaseous exchange occurs in the lungs and the air is expelled out. This expulsion of air is called expiration or exhalation. During this process, muscles attached to the ribs contract, the muscles of the diaphragm and the abdomen relax which leads to a decrease in the volume of the chest cavity and increases the pressure of the lungs, causing the air in the lungs to be pushed out through the nose.