Principles Of Gas Exchange Flashcards
(12 cards)
Transport type in CO2/O2 gas exchange
Simple diffusion
What is rate of diffusion directly proportional to?
A x pressure gradient
A = surface area
What else does diffusion rely on?
Physiochemical properties of the gas
Nature of the membrane: thickness
Diffusion capacity within lungs
40 m2
What cells line alveoli
Simple squamous epithelia cells
Pressure gradient in the lungs
The different i partial pressures of respective gasses in the alveolus and the blood
Partial pressure
The pressure a gas exerts if it were the only gas in the container
What is Dalton’s law
Partial pressure of gas in mixture = total pressure * fraction gas concentration
What is the fractional concentration of oxygen, carbon dioxide and nitrogen in the atmosphere?
21%
0
79%
Partial pressure of oxygen in the lungs is
Less than atmospheric oxygen pressure
why is partial pressure in the alveoli less than room pressure
- the inspired air is humidified in the upper airway
- in the alveoli oxygen is taken up while oxygen is added
- body consumes more oxygen that it produces CO2
What should be the alveolar partial pressure of oxygen be
13.7 kPa
