type I pneumocyte

cell

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July 14, 2026

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Type I pneumocytes are thin, flat cells that line the walls of the pulmonary alveoli in the lungs. They cover 92-95% of the gas-exchange surface and, along with endothelial cells, form the air-blood barrier essential for diffusion. This barrier allows oxygen to enter the blood and carbon dioxide to leave it. These cells are crucial for efficient gas exchange due to their thinness and the large surface area of the alveoli.123

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human respiratory system
The gas-exchange region
…thin, squamous cell type, the type I pneumocyte, covers between 92 and 95 percent of the gas-exchange surface; a second, more cuboidal cell type, the type II pneumocyte, covers the remaining surface. The type I cells form, together with the endothelial cells, the thin air–blood barrier for gas exchange; the…
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…thin, squamous cell type, the type I pneumocyte, covers between 92 and 95 percent of the gas-exchange surface; a second, more cuboidal cell type, the type II pneumocyte, covers the remaining surface. The type I cells form, together with the endothelial cells, the thin air–blood barrier for gas exchange; the…
Read More