lymphatic system

Question 1

what are the functions of the lymphatic system (3)

Answer 1

1. fluid balance
2. fat absorption
3. immunological defense

Question 2

what are the major organs involved in the lymphatic system?

Answer 2

• spleen
• thymus gland
• lymphatic vessels
• lymph nodes

Question 3

what is the lymphatic system ?

Answer 3

• system of vessels that works closely w circulatory system

Question 4

what is lymph

Answer 4

• clear watery liquid formed from interstitial fluid
• blood lfows through blood vessels –> fluid leaks out into surrounding tissues –> 90% diffuses back into capillaries 10%enters lymphatic vessels –> when interstitial fluid enters lymph vessel, its renamed lymph

Question 5

what are lymph capillaries

Answer 5

• ‘dead ends’ to lymph vessels
• lined w overlapping epithelial cells that allow fluid to enter
• capillaries open into large lymph vessels
• valves in vessels prevent backwards flow of fluid
• doesnt pump like blood: surrounding skeletal muscles provide pressure, pushes fluid along

Question 6

whats a lymph node

Answer 6

• small bean shaped structure that filters substances that travel through lymphatic fluid
• lymph vessels carry lymph to lymph nodes
• surrounded by capsule of connective tissue and formed by trebeculae (reticular fibers)
• inside, germinal centers are areas of rapid mitosis immune cells (lymphocytes) are quickly produced to fight off invaders in lymph
• cluster in areas like groin, axilary and are AREAS OF CAUTIO NFOR MASSAGE)

Question 7

where does lymph go after lymph nodes

Answer 7

• returned through 2 large ducts in chest: right lymphatic duct, thoracic duct
• ducts merge w veins where fluid reenter cardiovascular system

Question 8

what do other lymphoid organs do

Answer 8

• spleen and thymus
• protect body from infection but dont filter lymph

Question 9

what are lymph nodules

Answer 9

• loosly associated tissues not surrounded by capusule

Question 10

were is the spleen

Answer 10

• upper left part of abdomen
• spleen has 2 types of tissue:
• white pulp: lymphatic tissue and lymphatic nodules for filtering blood
• red pulp: removes wornout RBCs and serves as reservoir for stored blood

Question 11

where is thymus gland found

Answer 11

• part of endocrine and lymphatic system
• after t-lymphocytes are formed in bone marrow they travel to thymus for thymic education whre they learn to recognize specific foreign invaders (ARMY SCHOOL__LEARN TO FIGHT)
• t-lymphocyte production is regulated by thymus through release of hormone thymosin

Question 12

where are lymph nodules found

Answer 12

• associated w mucous membranes bc foreign invders become traped there (MALTS– mucosa associated lymphoid tissues)
• can be scttered within mucous membrane tissue or bundled together
  EX: appendix and tonsils

Question 13

role of tonsils in lymphatic

Answer 13

• accumulatio of lymphoid nodules on either side of throat
• form protective ring around throat to protect body from foreign invaders entering in through nose or mouth

Question 14

function of peyers patches and appendix in lymphatic system

Answer 14

• groups of lymphocytes near small intestine that filter bacteria from food and prevent benefiial bacteria from intestines from causing infection in rest of body

Question 15

lymphatic vessels

Answer 15

• lymph enters through afferent vessels (A COMES FIRST) and leaves through efferent vessels (E IS EXIT)

Question 16

what are cytokines

Answer 16

• small proteins released by immunce cells
• act as messengers to regulate bodys immune and inflammatory responses
• help signal other immune cells to move to areas of infection, injury or inflammation