Karteikarten
Unit 4 - Definitions & processes
Karten in diesem Stapel (18)
- 1natural killer cell-a specialized white blood cell
-releases cytokines which stimulate the specific immune response
-induce viral infected cells to destroy itself by apoptosis
-Causes the production of digestive enzymes inside the viral infected cell - 2Inflammatory response-caused by the release of h i s t a m i n e by m a s t cells
-this causes
1. vasodilation of arterioles which increase blood flow
2. increased capillary permeability
-increased blood flow and secretions of cytokines leads to
1. an accumulation of p h a g o c y t e s
2. delivery of antimicrobial proteins (to kill bacteria)
3. delivery of clotting elements which form a clot (to prevent microbes entering the bloodstream) - 3epithelial cells-form a physical barrier to prevent entry of pathogens (skin)
-produce secretions against infection (mucus in trachea, lysozome in tears, acid in the stomach) - 4phagocytes-a specialised white blood cell
-releases cytokines which stimulate the specific immune response
-recognise surface antigen molecules on pathogens and d e s t r o y them by phagocytosis - 5phagocytosiswhen a phagocyte e n g u l f s a pathogen
- 6immune surveillance????-a range of white blood cells constantly circulate tissues for signs of infection or damage
-if tissues become damaged or invaded, cytokines are released increasing blood flow
-results in specific white blood cells accumulating at the site of infection or damage - 7clonal selection theory-lymphocytes have a single type of membrane receptor which is specific for one antigen
-antigen binding leads to repeated lymphocyte division resulting in a clonal population of lymphocytes - 8lymphocytes-all cells have proteins on their surface called antigens
-the immune system can tell the difference between self and non-self antigens
-l y m p h o c y t e s respond specifically to antigens on f o r e i g n cells - 9foreign cellscells infected by pathogens
toxins released by pathogens? - 10pathogens phagocytesbad
good - 11immunological memory-some t and b lymphocytes survive long term as memory cells
-a secondary exposure to the same antigen rapidly gives rise to a new clone of lymphocytes
-a rapid and greater immunological response 2nd time - 12t-lymphocytes-they have specific surface proteins so they can tell the difference between self and non-self antigens
-some can destroy infected cells by inducing apoptosis
-some secrete cytokines that activates B-lymphocytes & phagocytes - 13what else do t-lymphocytes do?-when pathogens infect tissues, some phagocytes capture the pathogen & display its fragments of its antigens on their surface
-these antigen presenting cells (APC) activate the production of a clone of t-lymphocytes that move to the site of infection (under the direction of cytokines) - 14b-lymphocytes (part 1)each b-lymphocyte clone produces a specific antibody molecule that will recognize a specific antigen surface molecule on a pathogen or toxin
- 15b-lymphocytes (part 2)-Antibodies are Y-shaped proteins which bind to their specific surface antigen
-antigen/antibody complexes may 1. i n a c t i v a t e a pathpgen or toxin
or
2. render it more susceptible to pahagocytosis
or
3. stimulate a response causing cell lysis - 16b-lymphocytes (part 3)b-lymphocytes (activated by antigen presenting cells and t-lymphocytes) produce a clone of b-lymphocytes that secrete antibodies into lymph and blood where they may make their way to the infected area??
- 17immune system problems-auto immune disease & allergy-I.S. regulation failure leads to auto immune disease - this is when t-lymphocytes respond to self-antigens
-allergy is a hypersensitive b-lymphocyte response to an antigen that is normally harmless - 18—
Informationen
- Beschreibung
- Key areas 4.1and 4.2. unit 4 is green
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- katemacleod
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