W12 Cell death mechanism Flashcards
Define apoptosis
programmed cell death for removing old or damaged cells.
What are the three main types of cell death mechanisms
Apoptotic (Type I)
Autophagic (Type II)
Necrotic (Type III).
What are the physiological roles of apoptosis
Morphogenesis,
tissue remodelling
eliminating unwanted cells during development
Name two diseases associated with excessive apoptosis
Neurodegenerative diseases and organ failure
How is defective apoptosis linked to cancer
allows proliferative diseases to develop
what are the four hallmarks of apoptosis
Cellular shrinkage
chromatin condensation
DNA fragmentation
mitochondrial membrane permeabilization
What is the role of the Bcl2 protein family in apoptosis
regulate apoptosis by promoting/inhibiting cytochrome c release
What are caspases in apotosis
Proteases that mediate the intracellular proteolytic cascade
What is the extrinsic pathway of apoptosis
triggered by external death receptor signals like FAS
what is autophagic cell death
cytoplasmic material is degraded in autophagosomes
What triggers autophagic cell death
lots of autophagy
how to tell a cell has under go autophagic death
vacuolation without cell membrane breakage or inflammation
List two key functions of autophagy
Cellular survival through degradation and recycling of components
what is necrosis
cell death caused by trauma, infections, or chemical damage
what can necrosis lead to
inflammatory response
what is a hallmark of necrotic cell death
breaking of plasma membrane leading to cellular swelling
How do IAP (Inhibitor of Apoptosis Proteins) regulate cell death
binding to and inhibiting caspases
What are apoptotic bodies
fragments containing cellular material
Which proteins mediate mitochondrial-dependent apoptosis
Bax and Bak proteins
What role does the mitochondrial membrane potential play in apoptosis
for cytochrome c release and caspase activation
why is necrotic death inflammatory
loss of membrane integrity
What is the final step in autophagic cell death
fusion of the autophagosome with a lysosome
What is the autophagosome
a double-membrane vesicle during autophagy
What protein families regulate apoptosis
Bcl2 + IAP
what are the visible changes in apoptosis
cellular shrinkage
apoptotic bodies
chromatin condensation
membrane changes
what is released during apotosis
cytochrome c into cytosol
how does the plasma membrane change during apotosis
phospholipids switch
what is the role of intracellular calcium
activate signalling pathways
What do proteins like LAMP1 and HSP70 do in autophagy
prevent damage to lysosomal membrane
