Lymph nodes play an important part in the body’s defense against infection. The most common cause of swollen lymph nodes is infection, which might occur even if the infection is trivial or not. Afferent lymph vessels bring unfiltered fluids into the lymph node to be filtered while efferent vessels carry clean fluids away from the lymph node and to the cardiovascular system where it helps form the plasma in the blood.
Overall, lymph nodes work like a biological filtering system. When the body is invaded by foreign organisms, the painful swelling sometimes felt in the neck, armpits, groin, or tonsils comes from the microorganisms being trapped inside collections of lymph cells or nodes. Eventually, these organisms are destroyed and eliminated by cells that line the walls of the lymph nodes and the swelling and pain subside. Unsupported extension