Alveolar Ducts & Sac | Alveolar Sacs Function | Study.com
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The New York Times on Twitter: "Human lungs are made up of millions of microscopic, balloon-shaped air sacs called alveoli, the workhorse of the respiratory system, where the exchange of gases takes
Illustration of human alveoli. The alveoli are air sacs in the lungs, at the ends of the bronchioles, that allow the exchange of carbon dioxide and ox Stock Photo - Alamy