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Gas Exchange

7 videos
If you think of your lungs as a mini factory, you can think of the gases as goods that your body trades. Humans need oxygen for important metabolic activities. For example, when you exercise, your breathe more because your body needs more oxygen! These metabolic activities produce carbon dioxide, which is something your body needs to get rid of to avoid blood acidity. So, keeping with the example of your lungs as a factory, oxygen is an import good, and carbon dioxide is an export good! Learn more about the specific mechanisms of this “goods exchange” in the tiny air sacs of the lungs: the alveoli.

Alveolar gas equation - part 1

VIDEO 7:59 minutes
Find out how to calculate exactly how much oxygen is deep down inside your lungs! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes ...

Alveolar gas equation - part 2

VIDEO 7:06 minutes
Find out how to calculate exactly how much oxygen is deep down inside your lungs! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes ...

Henry's law

VIDEO 8:39 minutes
Explore the relationship between partial pressure of a gas and the concentration of the gas molecule within a liquid. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice ...

O2 and CO2 solubility

VIDEO 7:45 minutes
Get an intuition for why carbon dioxide is so much more soluble than oxygen when it goes into water. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for ...

Graham's law of diffusion

VIDEO 8:57 minutes
Find out whether oxygen or carbon dioxide has a higher rate of diffusion (Hint: It pays to be small!). Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for ...

Fick's law of diffusion

VIDEO 12:22 minutes
Learn all of the different ways to maximize the amount of particles that diffuse over a short distance over time. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and ...

Oxygen movement from alveoli to capillaries

VIDEO 11:46 minutes
Watch as a molecule of oxygen makes its way from the alveoli (gas layer) through various liquid layers in order to end up in the blood. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not ...