Topic : Gas Exchange and Ventilation

Question 1

What are the four properties of gas exchange surfaces?

Answer 1

1. Permeable to oxygen and carbon dioxide
2. A large surface area for diffusion
3. Thin, so the distance for diffusion is small
4. Moist, so oxygen can dissolve

Question 2

What are type one pneumocytes?

Answer 2

Extremely thin and permeable alveolar cells that are adapted to carry out gas exchange.

Question 3

What are type two pneumocytes?

Answer 3

Cells in the alveolus wall that secrete a fluid to keep the inner surface of the alveolus moist and allow gases to dissolve. The fluid also contains surfactant to prevent the sides of the alveoli from sticking together.

Question 4

How do blood capillaries affect gas exchange?