phagocytosis Flashcards
general outline of phagocytosis
virus and cell in contact with each other
virus binds to cell surface receptors
cell surrounds the virus and engulfs it into cell
virus is enclosed in a phagosome
fuses with lysosome = phagolysosome
pH is lowered to break down contents
phagolysosome forms a residual body which contains the waste products
what are opsonin receptors
bind bacteria thats coated with IgG.
tags them so other cells know it needs to be destroyed
what are opsonin receptors
cell surface receptors
bind bacteria that have been tagged with IgG
what is the complement system in really basic terms!?!
a group of proteins used to tag bacteria
^ destroy pathogens and threats to the host
what are scavenger receptors
bind to molecules that are produced by bacteria
what are toll-like receptors
bind to specific molecules produced by bacteria
once bound they recognise the specific bacteria and activate the immune response
what are cytokines and how do they relate to the immune response
cell signalling molecules
signal cells to move to a certain area in the body where the virus is found
what are pseudopods
a temporary projection of an eukaryotic cell membrane that is emerged in the direction of movement
how is the target found by the neutrophil
tagged by opsonins - including C3b and IgG
how are phagosomes produced
via pseudopods which extend from the neutrophil
how are phagolysosomes produced
phagosomes merge with lysosomes
how are ingested particles broken down during phagocytosis
lysosomal enzymes
reactive oxygen + nitrogen species
how is oxygen converted to superoxide and hydrogen peroxide
via the phagocyte oxidase enzyme
how is h2o2 converted to hypochlorite
myeloperoxidase
for phagocytes which is the most effective mechanism for killing microbes
O2-dependent killing
