G0, G1, S, G2, M
Gap 0 (G0): This is either a temporary or a more permanent resting period of the cell when it leaves the cell cycle and stop (i.e. quit) dividing.
Gap 1 (G1): In this stage, cells increase in size, produce RNA, and synthesize protein. The G1 checkpoint, which is a cell cycle control mechanism, is activated during this stage. This control mechanisms ensures that everything is ready for the synthesis of DNA.
S Phase: This is the synthesis phase where DNA replication occurs.
Gap 2 (G2): This is the gap (phase) between DNA synthesis and mitosis (somatic cell division) where the cell continues to grow and produce new proteins. The G2 checkpoint (control mechanism) is activated at the end of Gap 2 for the cell to determine whether or not it can proceed to enter the M phase (mitosis) and divide.
Mitosis or M Phase: At this stage, cell grown and protein synthesis is stopped and all of the cell's energy is used to drive the orderly and proper division of cells to produce two similar daughter cells.