During which process does the diaphragm contract, enlarging the chest cavity and creating negative pressure that pulls air into the lungs?

The process in which the diaphragm contracts to enlarge the chest cavity and create negative pressure that pulls air into the lungs is known as inspiration. During inspiration, the diaphragm moves downward, which increases the volume of the thoracic cavity. This increase in volume decreases the pressure within the thoracic cavity relative to atmospheric pressure, allowing air to flow into the lungs.

Understanding how the diaphragm functions during this process is crucial to grasping the mechanics of breathing. The contraction of the diaphragm, along with the intercostal muscles, facilitates the expansion of the lungs, making it possible for air to enter. This is the beginning stage of the respiratory cycle, which is essential for gas exchange in the body.