Respiratory - External Respiration

Question 1

What occurs during this stage?

Answer 1

Gas exchange between pulmonary blood and alveoli (movement of oxygen and carbon dioxide)

Question 2

How does diffusion occur across respiratory membrane?

Answer 2

Oxygen diffuses from alveoli (high pressure) into pulmonary capillaries (low pressure)

Carbon dioxide diffuses from blood in the pulmonary capillaries (high pressure) to alveoli (low pressure)