Lymphatic system Flashcards
WHAT IS THE FUNCTION OF THE LYMPHATIC SYSTEM
to maintain balance of fluids by returning excess fluid to the heart
allows the absorptuionof large molecules into the blood stream
fscilliates the immune system
HOW IS FLUID BALANCE MAINTAINED
protein and water seep out of the blood cappillaries and form part of the interstitial fluid which bathes the body cells with oxygen and nutrients
what happens to the 20 litres of interstitial fluid produces in a day
17 litres are absorbed back into the blood capillaries and 3 litres are not
what is lymph
lymh is the clear water like fluid that is contained in the lymhatic vessels
escribe the structure of lymphatic vessels
they start of as lymphati cappillares and contain single layer endothelial cells
the lymph vessels are 1 cell thik and these cells have overlapping cells whoch act as a one way valve that directs fluid directly intothe circulatory system with ni back flow
describe how lymph flows
when the pressure in the interstitial fluid is greater than the pressure in the lymph cappiliaries the valves open to allow fluid into the lympjh capillary
when the pressure of the interstitial fluyid is less than the pressure in the lymoph capillaries, the ymph nodes will snap shut
the lymph the travelsinto larger lymph vessels then into the lymph trunks and then the lymph ducts
how ae the lymphatic ducts formed
they start as the lymph cappillaries then they join to make the lymphatic vessels which join to make the lymph trunks which then join to form the lymphatic ducts
where are the lymphatic vessels located in he digestive system
they are located in the they are located in the wallsof the smll intestine and the digestive tract which has villi to increase surface area for nutrient absorption
the lympgh in the digestive sstem contains fat and is milky coloured and is called chyl
what causes lymph flow
contractions of the walls of the lymph vessels and the valvbes that prevent backflow
describe the l;ympyh nodes
the lymph nodes are ban or oval shaped and tgheir function uis to cleanse the lymph and detects any pathogens as it has b lymphocytes
they are more present in places prone to infection
describe the lymphatic tissue
the lymphatic tissue is reticular and lymphoid tissue
reticular cells - produce reticulin fibres which provide stricture
lymphatic tissue- contains immune and defence cells and lymphocytes
how many lymphatic trunks to we have
we have 9
2 lumbar trunks which drain the pelvis and lower limbs
2 bronchomediastinal which drain the chest
2 subclavian which deain the upper limbs
2 jugular which drain the neck
1 intestinal which drains the gut
how is the cisterna chyli formed
by the joining of 2 intestinal lymph trunks
what is the thoracic duct
it starts from tge cisterna chyli and it returns lymph from the pelvis to the subclavianvein
wherre do the left lymphatic duct and the thoracic duct drain lymph
right lymphatic duct - right subclavian vein
thoracic duct - right subclavian vein
