Immunity Topic 6 Flashcards
what is the definintion of an antigen?
Marker molecules that can be detected by antibodies and trigger an immune response.
what happens when a non self cell is detected
- triggers an immune response
what can be identified by different surface molecules?
- pathogens
- toxins
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Describe how macrophages ingest the bacteria
- macrophage phagocytoses bacteria / engulfs
- bacterium is held inside a vesicle
Explain how a person can develop artificial active immunity following vaccination.
- dead bacterium injected into person in vaccine
- stimulation of a specific immune response
- t-helper cells stimulated
- b cell activation
- t killer cells activated
- b memory cells activated to provide long term protection agaisnt infection.
State two characteristic features of antibodies.
- glycoprotein
- y shape
- light and heavy regions
- constant region
- variable region
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suggest how scientists could develop a means of producing active immunity against a HIV infection using a synthetic glycoprotein
- use of synthestic glycoprotein in a vaccine
- active artificial immunity
- stimulation of specific immune response
- t helper cells produce cytokines stimulating B cells
- b memory cells produced
- antibodies can be produced faster and in greater concentration
what are the three ways a non specific immune response occurs?
- inflammation
- phagocytosis
- interferons
what is the surface of the skin covered by to help protect agaisnt bacteria? (4)
- surface covered by oily sebum secreted by the sebacaeous glands
- provides a slightly acidic layer preventing the growth of harmful bacteria
- covered with harmless microorganisms
- they reduce the growth of pathogens by competing for rescources
what are the respiritory organs lined with the prevent pathogen entry?
mucusmembranes which secrete mucus that traps microorganisms which can then be destroyed by phagocytes
what white blood cells are in the non specific immune response?
phagocytes
- macrophages
- neutrophils
what happens when a neutrophil engulfs a bacterium? (3)
- it goes to a type of vacuole called a phagosome
- lysosomes move towards this forming a phagolysosome
- lysosomal enzymes break down the pathogen and destroy it
what can macrophages do that neutrophils cannot?
they can presnt antigens of enulfed bacteria (APC)
decribe the process of a macrophage becoming an APC in the non specific immune response (6)
- macrophage engulfs pathogen to form a phagosome
- lysosomes join to form a phagolysosome
- lysosomal enzymes digest the pathogen
- MHC binds to the antigens of the pathogen forming an MHC antigen complex
- the MHC antigen complex moves to the cell surface membrane and antigens are presented
- chemicals released called cytokines triggering cells to move to infected area
what is the role of the inflammatory response?
to bring WBCs to the site of infection to dispose of bacteria by phagocytosis
explain how white blood cells swarm to accumulate at the site of inflammation (4)
- histamine is released
- vasodilation then occurs at the arterioles
- increased blood flow to site of inflammation
- increased permeability of capillaries
- allowing WBC (blood plasma) moves from blood to tissue space
what is the role of the interferon?
- inhibit the production of viral proteins
- activate white blood cells that destroy infected cells
- increase the non specific response
