Question

Consider two mammalian cells, one in G1 and the other in G0 (stationary) phase. If they are stimulated to pass the restriction point by the addition of an extracellular proliferation signal, but the signal is then immediately removed, what would you expect to happen?

Answer 1

Answer:

In the mentioned case, both the cells will start to perform replication of their DNA. In the case of G0, that is, the stationary phase, the mammalian cell can pass the restriction point with the supplementation of extracellular proliferation signal. While in the case of G1, which actually does not require any kind of external proliferation signal, as once the cell is in G1 phase, it is ready to go get the next phase. However, both the mammalian cells will cease or halt at G2 checkpoint.