Cell Death Flashcards
what is necrosis
non programmed cell death
cells swell and burst
what causes necrosis
accidental trauma
what is apoptosis
programmed cell death requires ATP
when is apoptosis needed
defence
for development
what are the different types of apoptosis
extrinsic pathway and intrinsic pathway
describe the extrinsic pathway
extracellular signals bind to death receptor
cause them to cluster
adaptor proteins interact with the receptors through death domains
Death inducing signalling complex activates Caspase 8
causes a cascade of caspace 3/6/7
this cleaves cellular components
describe the intrinsic pathway
mitochondrial membrane changes
permeability increases so proteins are released into the cytoplasm ex) cyt c which activates caspace 9
what causes the mitochondrial membrane to change in the intrinsic pathway
negative factors - absence of hormones
positive - toxins infection, hypoxia, radiation
what mitochondrial protein interacts with caspace 9
Cyt C
which proteins regulate the release of Cyt C
Bcl2
Bcl - X - anti - aoptotic
Bax
Bid
Bad - pro - apoptotic
what occurs to the cell as it is getting apoptosed
cell and nucleus shrink
nuclear proteins + DNA + Chromatin condense
blebs form and bud of the cell
signals sent to macrophages to engulf apoptic bodies
what is autophagy
self eating
when is autophagy used
when the cell is starving, cell content is degrades by lysosomes
what are the markers in autophagy
ULK
Beclin
LC3
when does autophagy inhibit apoptosis
when conditions improve
