The collapse of alveoli during expiration is prevented by the
A) positive pressure in the pleural cavity
B) elastic recoil of the alveoli
C) thin film of serous fluid that lines the alveoli for lubrication
D) thin film of surfactant that lines the alveoli
E) cartilage that holds the alveoli open

Question

Quizplus · Accepted Answer

The thin film of surfactant that lines the alveoli reduces surface tension and prevents the collapse of alveoli during expiration.

The Collapse of Alveoli During Expiration Is Prevented by the