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Blood Vessels

3 videos
Where does your blood go after it leaves the heart? Your body has a fantastic pipeline system that moves your blood around to drop off oxygen and food to those hungry cells, and removes cell waste. Learn how arteries carry blood away from the heart, how veins bring blood back to the heart, and about the different layers of cells that make up these blood vessels.

Layers of a blood vessel

VIDEO 10:11 minutes
Remember the 3 key layers of a blood vessel (Tunica intima, Tunica media, and Tunica externa) and how arteries, veins, and capillaries are all different from one another. Rishi is a pediatric infectious disease physician and works at ...

Three types of capillaries

VIDEO 9:17 minutes
Learn the differences between continuous, fenestrated, and discontinuous capillaries, and how they affect the movement of molecules. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide ...

Pre-capillary sphincters

VIDEO 4:20 minutes
Find out how the body controls how much blood flows through a capillary bed. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. ...