lymphatics Flashcards
what is a lymph?
a tissue fluid that has not yet entered
blood capillaries
composition of lymph?
Similar to plasma,
– contains plasma proteins, dissolved gases,
lymphocytes, bacteria and other pathogens
– Contains fat
what does lymph do
Transports plasma proteins from capillary
beds back to blood stream
▪ Removes larger particles (e.g. bacteria & cell
debris) from damaged tissues – filters and
destroys them in nodes
what are lymph-capillaries ?
Blind-end tubes in interstitial spaces,
larger diameter than blood capillaries
▪ Single layer of endothelial cells which are
very permeable in one direction.
what do lymph-capillaries join up to form?
larger lymph vessels
All tissues of body have network of
lymph vessels expect for?
CNS and outer skin
semi-lunar valves within lymph vessels have a…
one way flow towards thorax
what is the movement of lymph determined by?
skeletal muscle movement
what are the 2 large ducts called?
thoracic duct & right lymphatic duct
what do the 2 ducts drain into?
Subclavian vein
functions of the lymphatic system
Tissue drainage Absorption in the small intestine Immunity 2 groups: Primary lymphatic organs eg bone marrow Secondary lymphatic organs eg lymph nodes
lymph nodes
▪ Oval or bean shaped – approx 600 in the body ▪ Deep & superficial ▪ Size pin-head to small almond ▪ Lie along vessels often in groups ▪ Lymph drains through a number of nodes (usually 8 to 10) before returning to venous circulation
Afferent
inward
Efferent
outward
what is the Parenchyma divided into
cortex & medulla