Lymphoid organs

Lymphoid organs are a part of the immune system that are involved in the production and maturation of lymphocytes, a type of white blood cell. They are classified into primary and secondary lymphoid organs.

Primary Lymphoid Organs

Primary lymphoid organs are where lymphocytes are formed and mature. They include the bone marrow and the thymus.

Bone Marrow

The bone marrow is the soft, spongy tissue found in the center of large bones. It is the primary site of new blood cell production or hematopoiesis. It produces both red blood cells and white blood cells, including lymphocytes.

Thymus

The thymus is a specialized primary lymphoid organ of the immune system. It is where T cells or T lymphocytes mature. T cells are critical to the adaptive immune system, where the body adapts specifically to foreign invaders.

Secondary Lymphoid Organs

Secondary lymphoid organs are where lymphocytes become activated. They include the lymph nodes, spleen, and mucosa-associated lymphoid tissue (MALT).

Lymph Nodes

Lymph nodes are small, bean-shaped structures that produce and store cells that fight infection and disease. They are a major site of B cells, T cells, and other white blood cells.

Spleen

The spleen is an organ located in the upper left part of the abdomen. It filters blood and maintains healthy red and white blood cells and platelets. It also produces lymphocytes as part of the immune response.

Mucosa-associated lymphoid tissue

Mucosa-associated lymphoid tissue (MALT) is a diffuse system of small concentrations of lymphoid tissue found in various submucosal membrane sites of the body, such as the gastrointestinal tract, nasal passages, thyroid, breast, lung, salivary glands, eye, and skin.

See Also

• Immune system
• White blood cell
• Bone marrow
• Thymus
• Lymph nodes
• Spleen
• Mucosa-associated lymphoid tissue

Lymphoid organs Resources
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