What function do alveoli serve in the respiratory system?

Alveoli are tiny air sacs located in the lungs and serve a crucial role in the respiratory system by allowing for the exchange of gases. Their primary function is to facilitate the exchange of oxygen and carbon dioxide between the air we inhale and the bloodstream. The walls of the alveoli are incredibly thin and are surrounded by capillaries, which enhances the diffusion process. When oxygen from the air enters the alveoli, it passes through the alveolar walls and into the capillaries, where it then binds to hemoglobin in red blood cells and gets transported to tissues throughout the body. Simultaneously, carbon dioxide, which is a waste product of cellular metabolism, moves from the blood into the alveoli to be exhaled. This efficient gas exchange process is vital for maintaining the body's oxygen supply and removing carbon dioxide, making the alveoli essential for effective respiration.