The lymphatic system is a collection of vessels and special organs known as lymphoid organs. They are important for the absorption and transport of lipids, mobilization of excess extracellular fluid, waste, and immune surveillance.
The basics
Components
- The fluid that flows through this system is known as lymph and consists of fluids filtered from the extracellular matrix — mostly from the blood.
- Lymphoid organs are divided into primary and secondary:
- Primary lymphoid organs include those where immune cells divide and develop: the bone marrow and thymus.
- Secondary lymphoid organs include those where most immune reactions occur: lymph nodes, spleen, tonsils (Waldeyer's tonsillary ring), MALT (mucous-associated lymphatic tissue).
- Lymph nodes are small, bean-shaped structures located in very important locations throughout our bodies, they contain a filtration system consisting of specialized immune cells.