Cellular growth and differentiation Flashcards
Does cell injury lead to necrosis or apoptosis?
Can do either! Necrosis by ATP loss or membrane destruction. But, radiation can cause overwhelming DNA damage, which then packs up and dies via apoptosis
What is the first stage in cell injury change?
Swelling
Accumulation of what ion most commonly contributes death of a cell?
Calcium
Ischaemia-perfusion injury is mediated by the accumulation of what ion?
Calcium
What is metaplasia?
Change in architecture cell layer. E.g. columnar metaplasia in barrett’s oesophagus. Squamous metaplasia in respiratory epithelium.
What is nuclear pyknosis?
Pinpoint pupil occurs during necrosis
What is nuclear karyorrhexis?
Break up of nucleus following pyknosis during necrosis
Do necrotic cells take more pink eosin stain or less?
More! They become more fab and pink when dying.
What is a feature of coagulative necrosis?
The cells are dead but they keep their architecture, opposed to liquifactive necrosis
Liquefactive necrosis causes what structures?
Cysts.
What family of proteins regulate apoptosis from external stimulation?
BCL2 family senors
What do the BCL2 family receptors act on in the apoptosis pathway?
Mitochondria
What do the mitochondria release to cause intrinsic apoptosis?
Cytochrom C
When mitochondira release cytochrome C to cause apoptosis, what do they act on?
Initiator capsases
What are the two receptors that enable extrinisic apoptosis?
TNF and Fas receptors
