Mechanisms of respiration in brief

Explanation:

Mechanism of respiration involves the breathing mechanism and exchange of gases. The gaseous exchange occurs by diffusion in the alveoli. It depends upon the pressure differences between blood and tissues, or atmospheric air and blood. The exchange of gases takes place at the surface of the alveolus.Mechanism Of InspirationThe process of intake of atmospheric air is known as inspiration. It is an active process.When the volume of the thoracic cavity increases and the air pressure decreases, inspiration takes place.Contraction of external intercostal muscles increases the volume of the thoracic cavity.Contraction of the diaphragm further increases the size of the thoracic activity. Simultaneously, the lungs expand.With the expansion of the lungs, the air pressure inside the lungs decreases.The pressure equalizes and the atmospheric air rushes inside the lungs.ExpirationThe expiration process is considered once after the gaseous exchange occurs in the lungs and the air is expelled out. This expulsion of air is called expiration.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.Mechanism Of ExpirationThe process of exhaling carbon dioxide is called expiration. It is a passive process.It occurs when the size of the thoracic activity decreases and the air pressure outside increases.Now the external intercostal muscles relax and the internal intercostal muscles contract.As a result, the ribs are pulled inwards and the size of the thoracic cavity is reduced.The diaphragm is relaxed and the lungs get compressed.Consequently, the pressure increases and the air is forced outside