Which phase of the cell cycle is characterized by the replication of $DNA$ and the synthesis of histone proteins?

The rate of cleavage is inversely proportional to the duration of

How many divisions occur when an isolated cell is divided into $128$ cells?

The most active phase of the cell cycle is .....

If a cell is diploid $(2n)$ in the $G_1$ phase,then in the subsequent $S$ phase,the cell will remain/become ........

It is observed that heart cells do not exhibit cell division. Such cells do not divide further and exit $G_{1}$ phase to enter an inactive stage called $G_{0}$ of cell cycle. Fill in the blanks.