Respiratory Physiology

Question 1

What does the pleural membranes line?

Answer 1

The inside of the thorax and cover the outer surface of the lungs.

Question 2

What are the functions of the pleural fluid?

Answer 2

It creates a slippery surface so that the opposing membranes can slide across one another as the lungs move within the thorax. It also holds the lung tight against the thoracic wall.

Question 3

What three main cell types does alveoli contain?

Answer 3

1. Type I cells (gas exchange).
2. Type II cells (produce surfactant).
3. Macrophages (phagocyte).

Question 4

What is the purpose of surfactant?

Answer 4

It reduces the surface tension preventing alveoli from collapsing and eases the expansion of lungs during breathing.