Lymphatic system
(a) Lymphatic vessels carry a clear fluid called lymph throughout the body. The liquid passes through (b) lymph nodes that filter the lymph that enters the node through afferent vessels, leaving through efferent vessels. Lymph nodes are filled with lymphocytes that purge infecting cells.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"Robert Bear and David Rintoul, Adaptive Immunity. December 11, 2013."
http://cnx.org/content/m47434/latest/
OpenStax CNX
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