In the G2 phase of the cell cycle, the cell grows, makes proteins and organelles, and begins to reorganize its contents in preparation for mitosis
. It follows the successful completion of the S phase, during which the cell's DNA is replicated
. G2 phase ends with the onset of prophase, the first phase of mitosis
. During this phase, the cell prepares itself for mitosis, and it is a period of rapid cell growth and protein synthesis
. The G2 phase is important for the cell to ensure that DNA replication has been successfully completed and to prepare for the subsequent mitotic phase
. It is regulated by the activity of the cyclin B1/CDK1 complex, also known as Maturation promoting factor (MPF)
