What Is the Lymphatic System?
4. Gross Anatomy - Lymph Nodes
Lymph nodes are small bean-shaped structures that are distributed along the lymphatic pathway as filtration mechanism for the lymphatic fluid before it is returned to the bloodstream. The average human has about 600 to 700 lymph nodes that are mostly found in the neck, armpits, groin, thoracic mediastinum, and mesenteries in the gastrointestinal tract.
It is the main line of defense that contains T lymphocytes and B lymphocytes. Lymph nodes contain both the cortex and medulla. in the cortex, there are follicles that contains collections of lymphocytes. In the center is the germinal center that contains B lymphocytes while the rest are T lymphocytes. The vessels entering lymph nodes are known as afferent lymphatic vessels while those exiting are known as efferent lymphatic vessels.
Advertisement
