Alveoli are tiny air sacs located in the lungs that play a crucial role in breathing. They are the final destination for the air we inhale, where oxygen from the air enters the bloodstream. Each alveolus is surrounded by a network of tiny blood vessels called capillaries, which help transport oxygen to the body's cells and remove carbon dioxide. These small structures are essential for efficient gas exchange. When we breathe out, the alveoli help expel carbon dioxide, a waste product of our body's metabolism. Healthy alveoli are vital for overall lung function, making it easier for us to stay active and energized.