What is the primary function of the alveolar sac?

The primary function of the alveolar sac is indeed to exchange gases in the pulmonary system. Alveolar sacs are clusters of tiny air sacs, called alveoli, where the exchange of oxygen and carbon dioxide occurs. This process is essential for respiration, as it allows oxygen from the air inhaled into the lungs to pass into the bloodstream and carbon dioxide, a waste product produced by the body's metabolism, to be expelled from the body.

Within the alveoli, the thin walls allow for efficient diffusion of gases. The structure is specifically designed to maximize surface area and facilitate this exchange, making it a crucial component of the respiratory system. This gas exchange is vital for maintaining the body's oxygen levels and removing carbon dioxide, thereby supporting cellular function.