22. Lung Function

Question 1

What are the partial pressures of oxygen and CO2 at rest?

Answer 1

O2: 100 mmHg
CO2: 40 mmHg

Question 2

What are the two separate blood supplies to the lungs?

Answer 2

Pulmonary

Bronchial - brings blood to lung parenchyma

Question 3

How much does the volume of blood vary by during exercise?

Why?

Answer 3

Rises from 75 mL at rest to 150-200 mL during exercise

Due to recruitment of new capillaries secondary to an increase in pressure and flow

Question 4

Why does the gas pressure gradient need to be much larger for O2 than CO2?

Answer 4

CO2 is more diffusible