What role does the diaphragm play in respiration?

The diaphragm is a crucial muscle for respiration, primarily responsible for assisting with lung inflation. When the diaphragm contracts, it moves downward, increasing the volume of the thoracic cavity. This decrease in pressure allows air to flow into the lungs, facilitating inhalation. As the diaphragm relaxes, it moves upward, which helps push air out of the lungs during exhalation.

While the diaphragm is integral to the breathing process, its primary function is related to creating the necessary changes in pressure for air movement, rather than other functions like regulating blood flow, filtering air, or directly facilitating gas exchange. Options that mention blood flow, gas exchange, or air filtration pertain to different aspects of respiratory physiology, but they do not define the diaphragm's primary role in the mechanics of breathing.