A. DNA synthesis starts shortly before 12 hrs after serum readdition. True

B. The R point transition occurs around 12 hrs after serum readdition. False

C. A suitable time window for measuring DNA synthesis is 12-16 hrs after
serum readdition. True

D. All cells sieze to replicate at 20 hrs after serum readdition. False but at this time several cells have already completed the S phase and are at G2/M.

E. Cells are more synchronized at the begining of S phase than during G2/M. True

F. E is true because G2/M can never be properly synchronized. False Several compounds can arrest cells in G2/M.

G. E is true because S phase is closer to the synchronization point (G0). True