Lymphatic System Flashcards
what is the lymphatic system comprised of?
lymph vessels, and nodes
what does the lymphatic system do?
collects excess fluid from the interstitial spaces and returns it to the heart
what does the venous end of the lymph capillaries do?
reabsorbs fluid pushed from the cardiovascular arterial capillaries into the interstitial space and the lymph picks up excess fluid
how does the lymphatic system operate?
without a pump using a series of valves to ensure the fluid travels in one direction back to the heart
what do the lymphoid organs do?
they are scattered through out the body and house phagocytic cells and lymphocytes that are essential to the bodys defense system and its resistance to disease
what are the lymphoid organs
spleen, thymus, tonsils, and the peyers patches of the intestine
what do lymphatic vessels do
lymphatic vessels are closed off at one end. after lymph fluid is picked up, it is circulated to increasingly larger lymph vessels called lymphatic vessels that empty their contents into either the right lymphatic duct or the thoracic duct
what does the spleen do
filters and destroys red blood cells that are no longer efficient. it serves as a blood forming organ early in life and later as a storage unit for extra red blood cells and platelets
what does the thymus do
responsible for t-lymphocyte maturation enabling them to function against specific pathogens in the immune response
what is the thymus
bi-lobed organ located in the upper thorax and can extend into the lower neck. after puberty the thymus starts to atrophy gradually
what are the tonsils
partially encapsulated lymphoid tissue in the throat. named according to their location
what are the three sections of tonsils
palatine tonsils
lingual tonsils
pharyngeal tonsil (referred to as adenoids if enlarged)
what are the Peyer’s Patches
found in the lining of the intestine and contain high levels of white blood cells, which help in fighting infection and disease, helps to protect against invading microorganisms
appendix
mass of lymphoid tissue attached to the first part of the large intestine, helps to protect against invading microorganisms
