Gas Exchange Flashcards
gas exchange relies on ____
diffusion
what increases diffusion?
- increased surface area
- increased solubility
- higher temperatures
- larger pressure differences
what decreases diffusion?
increased distance & molecular weight
what is the pressure of atmospheric air?
1 ATM = 760mmHg
what has similar solubility & binding to O2?
carbon monoxide
what is 20x more soluble than oxygen?
CO2
what is the percent of nitrogen, oxygen, and carbon dioxide in the air?
79% N
20.7% O2
0.3% CO2
what is the partial pressure of oxygen?
160mmHg
what is the partial pressure of nitrogen?
600mmHg
what is the pressure of oxygen in the lungs?
104mmHg
what is the pressure of CO2 in the lungs?
40mmHg
what is the pressure of oxygen in the tissue?
40mmHg
what is the pressure of CO2 in the tissue?
45mmHg
what is the pressure of oxygen in the cells?
<20mmHg
what is the pressure of CO2 in the cells?
46mmHg
what is the pressure of oxygen in the systemic veins?
40mmHg
what is the pressure of CO2 in the systemic veins?
45mmHg
what is the pressure of oxygen in the pulmonary artery?
40mmHg
what is the pressure of CO2 in the pulmonary artery?
45mmHg
to increase diffusion of a gas through a membrane, what physiological changes would occur to:
pressure gradient
cross-sectional area
solubility
distance
molecular weight
increase
increase
increase
decrease
decrease
which gas is often used to estimate the O2-diffusing capacity of the lungs?
carbon monoxide (CO)
