| Primary Lymphoid Tissue | Function |
|---|---|
| Bone Marrow | Development of all blood cells (hematopoiesis), including the initial development of lymphocytes, from cells called stem cells |
| Thymus Gland | Final development and maturation of lymphocytes from cells (Thymocytes) that migrate from the bone marrow to the Thymus Gland |
| Secondary Lymphoid Tissue | Function |
| Lymph nodes, Spleen, Mucosal Immune System | Sites of foreign antigen collection and lymphocyte response to foriegn antigen |