bio21.txt

  1. describe the fxn of the lympathic system:
    • fluid recovery: returns residual fluid not reabsorbed by capillaries, ~ 3L/day
    • immunity: detect anything harmful, and activate a protective immune response
    • lipid absorption
  2. describe the componets of the lymphatic system (and relate them to the cardiovascular system):
    • lymph: the recovered fluid
    • lymphatic vessels: transport lymph
    • lymphatic tissue: lymphocytes, macrophages that populate many organs of the body
    • lymphatic organs: concentrated lymphatic tissue, set off from surrounding organs by connective tissue capsules
  3. describe the formation and composition of lymph:
    • formation: tissue fluid that has been taken up by the lymphatic vessels
    • composition: recovered fluid, colorless, clear, if significant fat - then milky, has many lymphocytes
  4. describe the lymphatic capillaries:
    • penetrate nearly every tissue of the body, except the CNS, cartilage, cornea, bone, and bone marrow
    • close to blood capillires - except closed at one end
    • endothelial cells loosely overlap each other (roof shingles)
    • large molecules, can enter
    • passageways open + close depending on pressure inside and outside of vessels
  5. describe flow and mechanism of flow of the lymphatic vessels:
    • similar to veins, but thinner walls and more valves,
    • flow: flows at lower pressure and speed than venous return
    • mechanism of flow: rhythmic ocntractions of lymphatic vessels
  6. discribe the path of lymph flow from tissues to the bloodstream:
    • lymphathic capillaries
    • collecting vessels
    • lymphatic trunk
    • collecting ducts
    • subclavian vein
  7. describe the pathway of the right lymphatic duct pathway:
    • it receives lymphatic drainage from the right arm, right side of the thorax, and the head
    • then empties into the right subclavian vein
  8. describe the pathway of the thoracic duct:
    • the duct drains all of the body below the diaphragm, and the left upper limb and left side of the head, neck and thorax
    • then empties into the left subclavian vein
  9. describe the function and location of natural killer (NK) cells:
    fxn: attack and destory bacteria, transplanted tissues, or host cells turned cancerous
  10. describe the fnx and location of T lymphocytes (T Cells):
    • fxn: cellular immunity
    • location: mature in thymus, depen on thymic hormones
  11. describe the fxn and location of B lymphocytes (B cells):
    • fxn: humeral immunity
    • location: mature in bone marrow
  12. describe the fxn and location of macrophages:
    • phagocytize foreign matter/debris
    • presenting antigens
  13. list the two primary organs of lymphatics:
    • red bone marrow
    • thymus
  14. describe the fxn and locatio of red bone marrow as a lymphatic organ:
    • B cell lymphocytes maturation
    • produces all formed elements - squeeze thru endothelia cells into circulation
  15. describe the fxn and location of the thymus as a lymphatic organ:
    • T cell lymphoctye maturation
    • necessary for T cell development
    • very large in children
  16. list the secondary organs of the lymphatics:
    • lymph nodes
    • spleen
    • tonsils
  17. describe the fxn and location of the lymph nodes:
    • only organ to filter lymph
    • ~450 in young adults
    • lymph cleaned - 99% of impurities removed
    • site of T and B cell activation (initation site of immune response)
    • only lymph organ w/ afferant/efferant vessles
  18. describe the fxn and location of the spleen:
    • largest lymph organ
    • marcorphages digest old RBCs and phagocytize foreign matter
    • location: left hypochondriac region
  19. describe the fxn and location of the tonsils:
    • location: entrance of the pharynx
    • fxn: marchophages diegest old RBCs
    • gaurds agains ingested foreign matter
    • largest most infected organ
    • tonsillitis - inflammation fo the plaentine
  20. describe the lymphatic system used in the medical world:
    lymph nodes: become swollen when challenged, physisians palpate cervical, axiallary, inguinal

    cancer: metastasis (cancer cells) in lymphatics, lymphoma in lodge in lymph nodes - can be removed...but migrates to other nodes
Author
itzlinds
ID
135226
Card Set
bio21.txt
Description
lymphatic system
Updated