cell cycle g1 to mphase

M phase

The two sets of chromosomes are separated (mitosis) and the cell divides (cytokinesis).

G₁ phase

Cell doubles in size; organelles, enzymes, and other molecules increase in number.

G₁ checkpoint

is the main decision point for a cell - that is, the primary point at which it must choose whether or not to divide.

S phase

DNA replicated and associated proteins synthesized; two copies of cell's genetic information now exist.

G₂ phase

Structures required for cell division begin to assemble; chromosomes begin to condense.

G₂ checkpoint

ensures that the cell has successfully completed DNA replication and that the replicated DNA is undamaged before proceeding to cell division. This checkpoint is essential for maintaining genomic stability and preventing the proliferation of cells with damaged DNA.