The presence of surfactant in mammalian lungs
A) prevents alveolar collapse.
B) means that all alveoli must be the same size.
C) increases surface tension inside each alveolus.
D) is due to secretions from the tracheae.
E) is synthesised in the bronchiole cells.

Question

Quizplus · Accepted Answer

Surfactant reduces surface tension in the alveoli, preventing their collapse and allowing them to inflate more easily during breathing. It is produced by type II alveolar cells, not tracheae or bronchiole cells, and its presence allows for alveoli of different sizes to remain open.

The Presence of Surfactant in Mammalian Lungs