Kindly answer my query given in the following:-

The process by which oxygen rich air is taken up through the nostril into the body is known as inhalation. During inhalation, the chest cavity increases in size due to the downward movement of the diaphragm (dome shaped muscular sheet that separates chest from abdomen). As a result air from outside rushes into the lungs to fill the extra space.

Exhalation is the process by which carbon dioxide rich air comes out of the body. It occurs when the diaphragm moves up and the chest cavity becomes narrower. This creates a pressure on the air inside the lungs. As a result the air comes out of the lungs to the atmosphere due to lack of space inside. Both the process of inhalation and exhalation is commonly known as breathing.