During expiration the diaphragm becomes

Explanation

The process in which fresh air from the atmosphere reaches our lungs and impure air comes out of the lungs is called breathing(Breathing). This process is completed in two parts—(i) Inhalation (Inspiration), (ii) Exhalation (Expiration). In exhalation (Expiration), carbon dioxide (CO2)-rich air comes out of the lungs. In this, the ribs and diaphragm return to their normal position. The volume of the lungs decreases again. As a result, pressure on the lungs increases and carbon dioxide rich air is expelled from the body. During exhalation, the diaphragm is pulled upward and becomes dome-shaped.