RESPIRATION 3: Gas Exchange Flashcards
1
Q
What is partial pressure?
A
The pressure exerted by an individual gas in a mixture.
2
Q
Where does external respiration occur?
A
Between alveoli and pulmonary capillaries.
3
Q
Where does internal respiration occur?
A
Between systemic capillaries and body tissues.
4
Q
Why does oxygen diffuse into the blood at the alveoli?
A
Because its partial pressure is higher in alveoli than in capillary blood.
5
Q
What drives diffusion of gases?
A
Partial pressure gradients.
6
Q
What factors affect gas exchange?
A
Surface area, membrane thickness, pressure gradients, and gas solubility.
7
Q
What is the effect of pulmonary fibrosis on gas exchange?
A
Thickened membranes reduce diffusion efficiency.
8
Q
What is the typical partial pressure of oxygen in atmospheric air?
A
~160 mmHg
