Immunity Flashcards
What did Metchninkoff do?
proved that echinoderms are able to distinguish between self and non-self by sticking thorns into them and observing their response
what are the 3 characteristics of immunity
renaissance, recognition, response
what are the two forms of immunity?
innate and acquired
Describe the 1st layer of defence
the skin: mechanically blocks most pathogens and has a few elimination mechanisms
Describe the 2nd layer of defence
physiological change of internal conditions, e.g. lowered pH in the stomach
Describe the 3rd layer of defence
innate immune response consisting of roaming scavenger cells, phagocytosis takes place, and mobile cells may move to outer layer to spit out debris
Describe the 4th layer of defence
adaptive immune response - lymphocytes adapt to the structure of pathogens to eliminate them and store a memory
When did the immune system begin to evolve
over half a billion years ago
When and in what organism did acquired immunity first develop
around 500 mya in placoderm fish (early vertebrates)
Describe porifera immunity
innate, intercellular signalling with carbohydrate markers & signalling substances.
Which protein is responsible for binding together porifera cells after disturbance?
fibronectin
What is the purpose of melanin sythesis?
melanin has antiseptic properties and defends the organism (e.g. portifera) with protective pigmentation
Which 2 cells are used in endocytosis and lysozyme release in porifera?
exopinacocytes and mesohyl cells
Describe coelenterata (cnidaria & ctenophora) immunity
complex cell signalling & phagocytic activity (wound-healing), can produce non-specific anitmicrobials in the form of oxygen radicals and nitrogen oxide (which break up organic material), chitinase breaks up fungi, antibacterial enzymes.
What do gorgonians do to isolate/deactivate foreign material?
melanisation
