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Lymphatic system

5 videos
3B: Your heart pumps roughly 20 L of blood throughout the day to your tissues. The plasma component of blood (not containing blood cells) leaks out through capillaries (the tiniest of blood vessels) and is mostly reabsorbed. However, about 3L of the plasma is left behind in fluid surrounding tissues, and it is the job of the hard-working lymphatic system to bring back this fluid to the circulatory system. The lymphatic system moves fluid in one direction, but without the force of a pump like the heart.

Why we need a lymphatic system

VIDEO 9:32 minutes
Welcome to the lymphatic system! Find out why we need it, and how it interacts with our blood vessels. By Patrick van Nieuwenhuizen.

How lymphatic vessels move fluid

VIDEO 7:25 minutes
Find out how the body's mysterious second circulatory system works. Learn how it can move fluid even when it has no heart of its own. By Patrick van Nieuwenhuizen.

The lymphatic system's role in immunity

VIDEO 9:43 minutes
Learn about how B and T cells reside in lymph nodes. Find out how that enables them to get a preview of what they need to be prepared to fight. By Patrick van Nieuwenhuizen.

Lipid and protein transport in the lymphatic system

VIDEO 7:03 minutes
Learn about a third function of the lymphatic system. See how it finds a sneaky way to get fats and proteins into your bloodstream. By Patrick van Nieuwenhuizen.

What is actually in lymph

VIDEO 8:48 minutes
Learn about the differences between lymph and blood. Find out what is actually in lymph, and how it might be different across your body. By Patrick van Nieuwenhuizen.