What is the primary function of alveoli in the lungs?

The primary function of alveoli in the lungs is to facilitate gas exchange. Alveoli are tiny, balloon-like structures at the end of the respiratory bronchioles, and they play a crucial role in the respiratory system. Their walls are extremely thin and are surrounded by a network of capillaries, which allows for efficient diffusion of gases.

During respiration, oxygen from the air within the alveoli diffuses across the alveolar walls and into the capillaries, where it binds to hemoglobin in red blood cells. Conversely, carbon dioxide, which is a waste product of cellular metabolism, diffuses from the blood into the alveoli to be exhaled. This exchange of gases is vital for maintaining the body’s oxygen supply and removing carbon dioxide, a process essential for cellular respiration and overall metabolic function.

The structure of the alveoli, including their large surface area and moisture-lined surface, maximizes the efficiency of this gas exchange process, making them uniquely suited for their primary function in the lungs.