Lymphatic System

Lymphatic System Outline

Component

Lymph vessels Carry lymph from tissue spaces to the venous system, starts blindly  as lymph capillaries in tissue spaces, their walls are permeable  to substances of much  greater size Central Lymphoid Tissues Bone Marrow Produces all pluripotent lymphoid cells (in adults),  helps in differentiation of  B-Lymphocytes Thymus Helps in differentiation of T-Lymphocytes Peripheral Lymphoid Organs Lymph node Small nodules of lymphoid tissue found in the course of smaller lymph vessels,  purify the lymph from  harmful agents Spleen Removes old blood cells from circulating pool,  Keeps a reserve of  blood for emergency, Synthesizes antibodies Epithelio-   lymphoid tissues Lymphoid nodules in places like alimentary  canal and respiratory  tracts, Works as a  security check agains  all the incoming agents. Lympho- cytes        Mature B- and T-Lymphocytes circulating in blood, protects the body against any infectious agent that enters the blood

Functions

Removal of particulate matter, Production of lymphocytes, Generation of immune responses

Introduction to Lymphatic System

Lymphatic system is the drainage system of human body and is accessory to the venous system. At arterial ends of capillaries fluid leaks out and at the venous end, it is absorbed back in. Some of the fluid remains in the tissue spaces. This fluid is called lymph and the system by which this lymph is returned back to blood is called lymphatic system. In addition to its drainage function, lymphatic system is also an effective defense system of the body because some organs of the lymphatic system (lympho-reticular organs) are involved in defense activities of the body.

Lymphatic System 

(Source: TheEmirr/Wikipedia)

Components of Lymphatic System

Lymphatic system is composed of the following important components.epithelio-lymphoid tissues (lymphoid tissue present in epithelium e.g. lymphoid tissue of alimentary and respiratory tracts).

CIRCULATING POOL OF LYMPHOCYTES: It contains mature progenies of T-lymphocytes and B-lymphocytes. They form the first line of defense of the body during antigenic emergencies.

Functions of Lymphatic System

1. REMOVE PARTICULATE MATTER: Lymph capillaries absorb and remove large protein molecules and other particulate matter from tissue spaces. In this way cellular debris and other harmful particles are washed away.
2. FILTER THE LYMPH FOR FOREIGN HARMFUL PARTICLES: Lymph nodes act as filter for the lymph and in this way they purify the lymph flowing through them.
3. PHAGOCYTOSIS: Antigens are removed from lymph by phagocytic activity of cells of lymph node.
4. PRODUCTION OF LYMPHOCYTES: Mature B-lymphocytes and mature T-lymphocytes are produced in lymph nodes.
5. IMMUNE RESPONSES: Lymphatic system can induce both cellular and humoral immune responses.