What are the Key Histological Features of Alveoli?
Alveoli are characterized by their thin walls, composed primarily of type I alveolar cells (pneumocytes), which facilitate gas exchange. Type II alveolar cells are also present and are responsible for secreting surfactant, a substance that reduces surface tension and prevents alveolar collapse. The walls of the alveoli contain a rich network of capillaries, enabling close contact between air and blood.
