Definitions for most paragraphs

Question 1

Confluency

Answer 1

Confluency is a subjective estimation of the percentage of surface area that growing cells take up.

Question 2

Senescence

Answer 2

Cellular senescence is a complex state of stable cell cycle arrest in which proliferating cells become resistant to growth-promoting stimuli, typically in response to DNA damage. Senescent cells cannot re-enter the cell cycle and are characterised by morphological (flatter and large) and metabolic changes.

Question 3

p53

Answer 3

p53 responds to DNA damage by halting the cell cycle or triggering apoptosis

Question 4

Rb

Answer 4

Rb controls the G1–S phase transition via repression of E2F transcription factors.