What is the role of the diaphragm during respiration?

The diaphragm plays a crucial role in respiration by contracting to increase the volume of the thoracic cavity. When the diaphragm contracts, it moves downward, which creates a negative pressure within the thoracic cavity. This negative pressure allows air to flow into the lungs, facilitating inhalation. By expanding the thoracic cavity, the diaphragm enables the lungs to expand and fill with air.

This process is vital for effective breathing, as it directly influences airflow and gas exchange within the lungs. When the diaphragm relaxes, it moves back to its dome-shaped position, which decreases the volume of the thoracic cavity and helps expel air from the lungs during exhalation. In this way, the diaphragm is essential for both inhalation and exhalation, making it a fundamental component of the respiratory system.