UNIT 8 - LYMPHATIC AND IMMUNE SYSTEMS Flashcards
why do we need an immune system?
-defense against infections + tumors
what happens if the immune system does not work correctly?
-self cells can become injured
-inflammation can be induced
what are the good characteristics of our immune system?
-knows when to respond
-responds quickly to all potential pathogens (new and old)
-has an appropriate/effective response
-has memory in some cases
what are the aspects of an appropriate/effective immune response?
-targets foreign pathogens specifically
-no surrounding injury to self cells
-redundancy (back ups)
-diversity (changes tactics)
-regulation
what is an example of immunological memory?
-vaccines
-familiarizes the body
-increases memory
-increases repertoire
what are the 3 questions the immune system asks before responding?
-is it foreign?
-self or non-self
-is it dangerous?
-food is foreign but not dangerous
-clinical challenge?
-organ transplantation
what are the two branches of the immune system?
-innate immune system
-adaptive immune system
what are the functions of the lymphatic system?
-lymphatic capillaries absorb excess interstitial fluid and return it to the bloodstream
-lacteals (special lymph capillaries) in the small intestine absorb fats and transport them to the bloodstream
-helps in pathogen defense
-produces, maintains, and distributes lymphocytes in the body
what does the lymphatic system consist of?
-lymphatic vessels, organs, and fluids
what is carried within the lymphatic vessels?
-lymph
what are the beginning lymphatic vessels?
-blind-ended capillaries in tissues
what are the 2 lymphatic ducts?
-thoracic duct
-right lymphatic duct
where does the thoracic duct collect lymph from? where does it empty into?
-below the thorax (chest), left arm, left side of head and neck
-left subclavian vein
where does the right lymphatic duct collect lymph from? where does it empty into?
-the right arm, right side of head and neck
-right subclavian vein
how are the larger lymphatic vessels similar to veins?
-contain valves to prevent lymph from flowing backwards
what does the movement of lymph depend on?
-muscle contraction
what are the primary lymphoid organs?
-red bone marrow
-thymus
what are the secondary lymphoid organs?
-lymph nodes
-lymphatic nodules
-spleen
-tonsils
-peyers patches
what is the red bone marrow?
-site of blood cell production (produces 200 million daily)
-site of B lymphocyte maturation
what is the difference in red bone marrow in children and adults?
-most bones in children have red bone marrow
-only a few do in adults
-half of it is converted into yellow bone marrow by age seven
how much does red bone marrow weigh in adults?
-2.7Kg
what happens to the yellow bone marrow during emergencies?
-body converts yellow bone marrow to red
-to help keep you alive
what is the thymus?
-bilobed organ (2 lobes)
-produces thymosin
-site of T lymphocyte maturation (move from the red bone marrow)
what is the function of thymosin?
-induces T lymphocyte maturation