What are alveolar sacs?

Alveolar sacs, or pulmonary chambers, lie within our lungs, and are located at the end of the alveolar duct. They are small globular type entities that hang in a bunch, rather like grapes. In fact, if you saw inside the lungs you would immediately think of bunches of grapes with the alveolar ducts like branches holding the bunches.

But to imagine a sac like a grape is deceptive, for the alveolar sacs are pockets holding several individual alveoli. The function of the alveolar sacs is to allow oxygen and carbon dioxide to move between the lungs and bloodstream. Therefore, they are very important in the human respiratory system. As with other things, the alveolar sacs lose their functionality with ageing