Function of Alveoli
Answer (1)
Here's a more detailed explanation:Gas Exchange:Alveoli are tiny, balloon-shaped air sacs located at the end of the bronchioles in the lungs. They are surrounded by capillaries, which are tiny blood vessels. Oxygen Uptake:When you inhale, air fills the alveoli, and oxygen moves across the thin walls of the alveoli and capillaries into the bloodstream. Carbon Dioxide Removal:Simultaneously, carbon dioxide, which is carried in the blood from the rest of the body, diffuses from the capillaries into the alveoli. Efficient Surface Area:The large number of alveoli (millions in each lung) creates a vast surface area for efficient gas exchange. This is similar to how villi in the digestive system increase the surface area for nutrient absorption. Alveolar Cells:Alveoli are lined with specialized cells: Type I alveolar cells: These cells are thin and flat, facilitating rapid diffusion of gases. Type II alveolar cells: These cells produce surfactant, a substance that reduces surface tension and prevents the alveoli from collapsing. Air-Blood Barrier:The close proximity of the alveolar cells and the capillary endothelium, with a shared basement membrane, forms a thin air-blood barrier that allows for efficient gas exchange.
