1.5d Control of Programmed Cell Death (apoptosis) Flashcards
1
Q
What is apoptosis triggered by?
A
Cell death signals that can be internal or external
2
Q
What is an example of an external death signal?
A
The production of death signal molecules from lymphocytes
3
Q
What is an example of an internal death signal?
A
DNA damage
4
Q
How do external death signals work?
A
- External death signal molecules bind to a surface receptor protein and trigger a protein cascade within the cytoplasm
5
Q
What causes activation of p53 tumour-suppressor protein?
A
An internal death signal resulting from DNA damage
6
Q
What do both types of death signal result in?
A
activation of caspases (types of protease enzyme) that cause the destruction of the cell
7
Q
What are caspases?
A
types of protease enzyme
8
Q
What is the role of apoptosis in development of an organsim?
A
- to remove cells no longer required as development progresses or during metamorphosis
9
Q
When may cells initiate apoptosis?
A
in the absence of growth factors
