Inhalation is the physical process by which the air containing oxygen is drawn into the lungs.
Exhalation is the physical process by which the air containing carbon dioxide is forced out from the lungs.
Differences between Inhalation and Exhalation are:
| Inhalation | Exhalation |
|---|---|
| Ribs move upwards and outwards. | Ribs move downwards and inwards. |
| Diaphragm is pushed downwards and flattens. | Diaphragm moves upwards and becomes dome-shaped. |
| Volume of chest cavity increases. | Volume of chest cavity decreases. |
| Lungs expand, air pressure becomes low. | Size of the lungs reduces, air pressure becomes high. |
| Atmospheric air at a higher pressure rushes into lungs. | Air rushes out of the lungs as atmospheric air pressure is lower. |