LYMPHATIC SYSTEM Nada AL-Juaid

lymphatic system  The lymphatic system is part of the circulatory system,circulatory system

Lymphatic system consists of: 1. lymph 2. Lymphatic vessels 3. Structures and organs containing lymphatic tissue 4. Red bone marrow

Functions of Lymphatic system  Drain interstitial fluid  The lymphatic system also removes excess fluid, and waste products from the interstitial spaces between the cells.  Transport dietary fats  absorb lipids from the intestine and transport them to the blood  Carry out immune responses  defend the body against disease by producing lymphocytes

Lymphatic organs and tissues A. Primary Lymphatic organs:  Thymus gland  Bone marrow B. Secondary Lymphatic organs:  Lymph nodes  Spleen  Tonsils  Peyer’s patches  appendix

Primary Lymphatic organs  Thymus gland  The thymus secretes a hormone, thymosin, that causes pre-T-cells to mature (in the thymus) into T-cells.

Primary Lymphatic organs  Bone marrow  Bone marrow: Is the soft tissue found in the hollow Interior bones.  marrow in large bones produces new blood cells.

Bone marrow  There are several different types of white blood cells. white blood cells are often characterized as granulocytes or agranulocytes

Bone marrow  Granulocytes (polymorphonuclear leukocytes): leukocytes characterised by the presence of differently staining granules in their cytoplasm when viewed under light microscopy.  There are three types of granulocytes: neutrophils, basophils, and eosinophils, which are named according to their staining properties.neutrophils basophilseosinophils  Agranulocytes (mononuclear leukocytes): leukocytes characterized by the apparent absence of granules in their cytoplasm.granulescytoplasm  These include lymphocytes, monocytes, and macrophages.lymphocytesmonocytes macrophages

Secondary Lymphatic organs  Lymph nodes  There are between lymph nodes present in the average human body.  It is the role of these nodes to filter the lymph before it can be returned to the circulatory system.  Although these nodes can increase or decrease in size throughout life, any nodes that has been damaged or destroyed, does not regenerate.

Secondary Lymphatic organs  Lymph nodes  Located along lymphatic vessels  Covered by capsule  Trabeculae divide node into compartments  Contain B cells, T cells,dendritic cells, and macrophages

Secondary Lymphatic organs  Spleen  Connective tissue capsule with internal trabeculae  The spleen behaves similar to a lymph node but instead of filtering the lymphatic fluid it filters the blood. Red Pulp: Clusters of Macrophages and Red Blood Cells. White Pulp: Lymphocytes and Macrophages,

Secondary Lymphatic organs  Tonsils  are area of lymphoid tissue on either side of the throat.  Tonsils refers to the Palatine tonsils,that can be seen on the left and right sides at the back of the throat.

Secondary Lymphatic organs Tonsils Tonsils : helping fight off pharyngeal and upper respiratory tract infections. Other types are pharyngeal tonsils and lingul tosils

Secondary Lymphatic organs  Peyer’s patches  Peyer's patches are lymphoid follicles located in the wall of the small intestine.

Secondary Lymphatic organs  appendix

References   obk/biobookimmun.html obk/biobookimmun.html  on%202%20Notes.pdf on%202%20Notes.pdf