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The alveoli consist of an extremely thin epithelial layer and an extracellular matrix (a fluid space made of collagen and elastin that contains no cells) it is surrounded by many capillaries, the tiniest type of blood vessel.
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Carbon-dioxide-rich blood is pumped from the rest of the body into the alveolar blood vessels where, through passive diffusion, it releases its carbon dioxide and absorbs oxygen into the blood vessels. The alveolar membrane is the gas-exchange surface. Its plural is alveoli, from the Latin alveolus, meaning little cavity.įound in the lung parenchyma, the pulmonary alveoli are the terminal ends of the respiratory tree that outcrop from either alveolar sacs or alveolar ducts both are sites of gas exchange with blood. Pulmonary surfactant: Pulmonary surfactant is a surface-active lipoprotein complex formed by type II alveolar cells that maintains the elastic recoil of the lung.Īn alveolus is an anatomical structure that has the form of a hollow cavity.extracellular matrix: A fluid space secreted by cells (including alveolar cells) for structural and functional support.alveolar dead space: Alveolar space that can no longer contribute to gas exchange due to damage or scarring.It is a common symptom of many lung diseases. Alveolar dead space occurs when an alveolus can’t participate in gas exchange due to damage, injury, scarring, or infection.Insufficient pulmonary surfactant in the alveoli can contribute to the collapse of a lung.
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The alveoli consist of an epithelial layer and an extracellular matrix surrounded by capillaries.Carbon-dioxide-rich blood is pumped from the rest of the body into the alveolar blood vessels where, through diffusion, it releases its carbon dioxide and absorbs oxygen. The alveolar membrane is the gas-exchange surface.The pulmonary alveoli are the terminal ends of the respiratory tree that outcrop from either alveolar sacs or alveolar ducts both are sites of gas exchange.An alveolus is an anatomical structure that has the form of a hollow cavity and is found in the lung parenchyma ( tissue inside the lung).
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