Respuesta :
The immune system is the bodies defense against invaders and is located in all body tissues with concentration in the mucosal surfaces and skin.
Answer:Primary lymphoid organs: These organs include the bone marrow and the thymus. They create special immune system cells called lymphocytes. Secondary lymphoid organs: These organs include the lymph nodes, the spleen, the tonsils and certain tissue in various mucous membrane layers in the body
Explanation: BRAINLIEST pls