Anatomy, Ch. 15, Lymphatic Sys

hrdcorhrvivor's version from 2017-03-19 05:11


Question Answer
lymphintersitial fluid located within lymph vessels and tissue
lymphatic tissuespecialized form of reticular CT, contains large numbers of lympocytes
functions of lymphatic systemdrains excess intersitial fluid, transports lipids from GI tract, carries out immune responses against antigens
B cells15-30% involved in humoral immunity, plasma cells: produce antibodies, memory b cells: remember the antigen, faster immune response later
t cells 70-85% responsible for cell mediated immunity
lymphatic capillariesgreater permeability than blood capillaries, slightly larger than blood caps, one way structure only in not out, caps in GI tract are called lacteals, lymph from FI tract creamy white chyle
lymph flow from intersitial fluid back to heartlymph capillaries, lymph vessels, lymph nodes, to lymph trunks, subclavian veins
lumbar trunksdrain from lower limbs, kidneys, adrenal glands
intestinal trunkdrain from GI tract and spleen
bronchomediastinal trunksdrain lungs, heart
subclavian trunksdrain upper limbs
jugular trunksdrain head and neck
lymphatic ductsfrom the trunks, lymph drains into two main ducts. right lymph duct: smaller, receives lymph from R jugular, R subclavian, and R bronchomediastinal truns. thoracic duct: begins at cisternae chyli, receives lymph from lumbar trunks and intestinal trunk, left side and entire body lower than ribs
primary lymphatic organssites where stem cells divide and become able to mount an immune response. red marrow, thymus
secondary lymphatic organs and tissuessites where immune response occur. lymph nodes, spleen, lymphatic nodules
thymusencapsulated, trabeculae: divides thymus into lobules. lobule: cortex has t cells, dendritic cells, epi cells ->thymic macrophages. medulla: mature t cells, dendritic cells, epi cells ->thymic corpuscles. mature t cells leave thymus and enter lymph node and spleen
lymph nodesscattered throughout body, encapsulated with trabeculae, stroma: supportive CT of lymph nodes. paraenchyma: functional region of lymph node
lymph node parenchyma outer cortexaggregates of b cells called lymphatic nodules, primary lymphatic nodule has b cells, secondary has plasma cell and memory cells. germinal center within secondary lymph nodule, b cells in antigens, memory cells persist after immune response, plasma cells create antibodies
lymph node parenchyma inner cortex and medullainner: no lymphatic nodules, mostly t cells and dendritic cells, t cell activation. medulla: b cells, plasma cells
flow of lymph through lymph nodesenters through afferent lymphatic vessels, inward toward sinuses. subscapular sinus: deep to capsule. trabecular sinus: through cortex. efferent sinus: through medulla. leaves the efferent sinus and exits via efferent lymphatic vessel at hilium
spleenlargest lymphatic organ, encapsulated. parenchyma: red pulp and white pulp
red pulp venous sinuses filled with blood and splenic cords filled with WBC and RBC. removal of old damaged RBC, store platelets, production of blood cells during fetal development
white pulplymphocytes and marcophages, arranged around central arteries immune cells B cells, T cells, and macrophages activated and destroy blood borne pathogens
lymphatic nodulesmasses of lymph tissue with no capsule, scattered throughout CT and mucous membranes of GI tract, urinary, reproductive, respiratory tracts. MALT (mucosa associated lymphoid tissue) EX: tonsils respond to inhaled or ingested foreign material, peyer's patches in small intestine