##  [Pulmonary Alveolus](/index.php/pulmonary-alveolus) 

  ##  [Pulmonary Alveolus](https://health.quantumdictionary.io/pulmonary-alveolus-0) 

  

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**Health & Life Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A microscopic terminal airspace in the lung lined by thin epithelial cells (type I and II pneumocytes) and closely apposed to pulmonary capillaries, where gas exchange between inspired air and pulmonary capillary blood occurs across a minimal diffusion barrier and where surfactant and fluid balance maintain surface tension and patency.