Phagocytosis Flashcards
what type of response is phagocytosis and why?
- non specific
- same response for all pathogens
briefly describe phagocytosis
phagocytes (macrophages and neutrophils) travel in the blood and squeeze out of capillaries to engulf and digest pathogens
stage 1 (cytokines)
damaged cells and pathogens release cytokines which attract phagocytes to the site of infection
what are cytokines?
cell signalling chemicals
stage 2 (opsonins)
opsonin proteins attach to pathogens to mark them which makes it easier for pathogens to engulf them
stage 3 (receptors)
phagocyte receptors attach to chemicals on pathogen surface
stage 4 (engulf)
phagocyte engulfs pathogen into a vesicle, forming a phagosome
stage 5 (lysosome)
lysosomes containing lysozyme fuse with phagosome and hydrolyse the pathogen
stage 6 (absorb)
phagocyte cytoplasm absorbs any useful soluble molecules
stage 7 (APC)
phagocytes present pathogen antigens on the surface, becoming an antigen presenting cell