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Respiratory system

9 videos

Meet the lungs

VIDEO 9:36 minutes
Every time you take a breath, oxygen makes it way into your lungs. Follow along on that journey! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Inhaling and exhaling

VIDEO 12:59 minutes
Find out exactly why air goes in and out of the lungs. Rishi is a pediatric infectious disease physician and works at Khan Academy.

How does lung volume change?

VIDEO 8:10 minutes
Learn about how muscle contraction and lung recoil actually help the lungs change their volume with every breath! Rishi is a pediatric infectious disease physician and works at Khan Academy.

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 ...

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 ...

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 ...

The respiratory center

VIDEO 9:23 minutes
Find out how the respiratory center collects information from all over the body and then helps regulate your breathing. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical ...