8.4 The Lymphatic System

Question 1

What happens in the lymphatic system? (x3)

Answer 1

-B cells proliferate in areas called germinal centers
-Returns fat via lacteals to general circulation from the GI tract
-Returns excess fluids from the interstitial space

Question 2

Where does the lymphatic system return its contents to the general circulation?

Answer 2

The thoracic duct in the posterior chest, to the left subclavian vein

Question 3

Why is fluid left over for the lymphatic system.

Answer 3

Because the net pressure drawing fluid in at the venule end is slightly less than the net pressure pushing fluid out at the arterial end, a small amount of fluid remains in the tissue.

In other words, there’s more osmotic pressure than hydrostatic pressure at the end of the venule.

Question 4

Why does edema occur?

Answer 4

When the lymphatics are overwhelmed, fluid will stick away, resulting in edema.

Question 5

What is chyle?

Answer 5

Lymphatic fluid carrying many chylomicrons with a milky white appearance.