lymphatic system Flashcards
how does lymph differ from plasma?
lymph contains white blood cells
lymph might carry __________ from a site of infection and ______ cells from cancerous tissue.
bacteria
tumor
why can we see lymph after a high fat meal?
in the gut, the lymph is rich in lipids
why prevents backflow in lymph?
valves
where does lymph get filtered at?
lymph nodes
what vessels join to form larger lymph vessels?
efferent
where does lymph ultimately drain into that empties into the cranial vena cava and mixes with the blood stream?
thoracic duct
what is the primary lymphoid organ that T lymphocytes originate from?
thymus
what is the primary lymphoid organ which generates T and B lymphocytes and macrophages?
bone marrow
list secondary lymphoid organs
GALT, BALT, MALT (tonsils, adenoids), spleen, lymph nodes
Except for the thymus, lymphocytes in all these organs are organized into nodular structures called ________ or they can be found dispersed diffusely in the organ/tissue
follicles
what part of the thymus do mature T lymphocytes reside?
cortex
what part of the thymus do immature T lymphocytes reside?
medulla
what cells make up the framework of lymphoid organs?
stromal cells
In the thymus, the stromal cells called _________________ form whorls called “______________”.
epithelial reticular cells,
Hassal’s corpuscles
Hassal’s corpuscles are apparent in the medulla of thymus from older animals as the thymus ________
atrophies
what are examples of secondary lymphoid organs?
lymph nodes and spleen
what is the cortex of the lymph nodes filled with?
follicles
what do the follicles have of the lymph node that is made of mature B lymphocytes?
mantle zone
the inner core of the follicles of lymph nodes have what that is made of immature B lymphocytes?
germinal center
in the cortex of lymph nodes, how are the T cells distributed in non-follicular regions?
parafollicular zone
what is the medulla of the lymph nodes composed of?
cords and sinuses
list the path lymph filters through lymph nodes
outer regions of lymph nodes -> medulla -> efferent lymph vessels
what is the purpose of the spleen?
site where all RBCs that reach the end of their lifespan are recycled
true or false: the spleen has a cortex and medulla
false
true or false: the spleen has follicles (made of B lymphocytes) that are evenly distributed in the spleen
true
Splenic blood vessels are encapsulated by ______________ and form “____________________”.
T lymphocytes,
periarteriolar lymphatic sheaths or PALS
what does the central arteriole divide and give rise to?
penicillar arterioles
list the flow of blood in the spleen
arteries -> central arteriole -> penicillar arteriole -> sinusoidal capillaries -> splenic venules and veins
in the splenic sinuses, what digest the RBCs and recycle iron?
macrophages that sit on splenic cords
what is the region of the spleen where lymphocytes are present?
white pulp
what part of the spleen is of the splenic sinuses where there are RBCs?
red pulp
what is the lymphocyte aggregation called particularly in the ileum of the small intestine?
peyer’s patches
what is the lymphocyte aggregation called particularly surrounding larger airways in the lungs?
BALT
