Bronchioles are small passageways in the respiratory tree that are free from cartilage and glands. They are formed by the repeated branching of larger bronchi and are part of the system that conducts air towards the site for gas exchange.
Terminal bronchioles are lined by simple columnar epithelia containing club cells that secrete surfactant. What is the
function of surfactant?
A)
Surfactant is a hormone secreted to regulate gas exchange in the alveoli
B)
Surfactant provides a fluid medium for the dissolving of gases in the
alveoli
C)
Surfactant prevents the bronchioles and alveoli from collapsing during
expiration.
D)
Surfactant traps any pollutants and dust particles that have made it
through the respiratory passages.