出典:Wikipedia
出典:『Wikipedia』 (2011/05/30 04:41 UTC 版)
Type I pneumocytes (simple squamous alveolar cells) are responsible for gas exchange in the alveoli and cover a majority of the alveolar surface area (>95%). While type I pneumocytes account for most of the surface area, they are approximately half as numerous as type II cells, due to differences in size. Type I pneumocytes are large, thin cells stretched across a large surface area, while type II pneumocytes are smaller cells.