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In the alveoli, oxygen from the air is absorbed into the blood. Carbon dioxide, a waste product of metabolism, travels from the blood to the alveoli, where it can be exhaled. Between the alveoli is a thin layer of cells called the interstitium, which contains blood vessels and cells that help support the alveoli.
What are Alveoli. Alveoli are the small balloon-like sacks of 200-500Î¼m diameter [1], making up a vital part of the respiratory zone of the human lungs. Each alveolus (singular) plays an important role in letting oxygen and carbon dioxide move into and from the bloodstream during inhalation and exhalation [2, 3]. Where are the alveoli found. The alveoli are all interconnected with each other, forming the final part of the bronchial tree. Originating from the alveolar duct located at the end of each bronchiole [4], there may be multiple alveoli arising from a single duct, often existing in clusters [2]. How Many Alveoli are Found in Each Lung