What is the role of the alveoli in the respiratory system?

The alveoli play a crucial role in the respiratory system primarily by facilitating gas exchange. These tiny, balloon-like structures are located at the end of the bronchioles in the lungs and are surrounded by a network of capillaries. When air reaches the alveoli, oxygen from the inhaled air passes through the thin walls of the alveoli and into the bloodstream, where it binds to hemoglobin in red blood cells. Simultaneously, carbon dioxide, which is a waste product of cellular respiration, moves from the blood into the alveoli to be exhaled.

This gas exchange is vital for maintaining the body’s oxygen supply and removing carbon dioxide, essential for cellular function and maintaining acid-base balance in the body. The large surface area provided by the numerous alveoli increases the efficiency of this exchange, making them integral to respiratory function.