lymphatic system Flashcards
what is interstitial fluid?
fluid pushed out of vessels and into the tissues, occurs at the capillary level, most fluid is picked up and returned to the venous system
what is lymph?
interstitial fluid picked up by the lymphatic system, a fluid connective tissue
what is the lymphatic system and its function?
consists of lymph vessels and lymphoid tissues and organs, function: returns interstitial fluid back to blood stream, initiates an immune response when necessary, transports dietary lipids
what are lymphatic capillaries?
smallest of lymph vessels, wall composed of endothelium, walls have one way flaps
what are lacteals?
in the small intestine, carries interstitial fluid and dietary lipids and some vitamins
what are lymphatic vessels?
has 3 tunic layers and valves, take lymph to and from lymph nodes
what are lymphnodes?
filter lymph and collect pathogens
what is lymphedema?
swelling caused by lymphatic vessels results in increased interstitial fluid
what are lymphatic trunks?
formed from merging lymphatic vessels and drain into lymphatic ducts
what is the right lymphatic duct?
receives lymph from right ride of head, neck, and thorax, drains into right subclavian vein
What is adaptive immunity?
defense mechanism which are developed in response to contact with antigens, slower response and memory, cells produce immune response when exposed to antigens
what is innate immunity?
the defense mechanism present at birth, non-specific/rapid response
what is the thoracic duct?
receives lymph from left side of head, neck, and thorax, drains into left subclavian vein
what do B-lymphocytes do for immune system?
secrete antibodies
what do epidermal dendritic cells do?
phagocytize bacteria
what do dendritic cells do?
internalize antigens and present them to lymphocytes
what do T-lymphocytes do for immune system?
some of these cells manage/direct and immune response while others attack
what is a lymphoid structure?
consists of connective tissue containing a lot of lymphoid cells, not surrounded by a connective tissue capsule
what are lymphoid nodules?
clumps of lymphoid cells within other organs, in the GI, respiratory and genitourinary tract, destroy bacteria before they breach the intestinal wall and generate memory cells
what are lymphoid organs?
lymphatic structures surrounded by connective tissue capsule, like lymph nodes, thymus, and spleen
what is the thymus and function?
behind the sternum, T-cells mature and differential here, T-lymphocytes are sent from bone marrow into the thymus, secretes hormones to help T-lymphocytes develop
what is the spleen and funtion?
largest lymphoid organ, located in upper left abdomen, has two parts, carries out an immune response when antigens are found in blood
what is the red pulp?
part of spleen that removes old erythrocytes and platelets, contains erythrocytes, platelets, and macrophages, also contains splenic sinusoids and splenic cords
what is the white pulp?
part of spleen that carries out immune responses when antigens are found in the blood, contains lymphocytes B and T cells, and surrounds arterial branches
