interphase

G0 stage

cells exit interphase and stop prep for cellular division

G stage

growth stage

S stage

synthesis

What is S stage

DNA is replicated; chromosomes are doubled to proper number of chromatids

chromatids

chromosomes

sister chromatids

two identical chromatids

Cell cycle steps

G0; G1; S; G2; Prophase; Metaphase; Anaphase; Telophase; cytokenisis

G2 stage

cell synthesizes proteins that assist in cell division

What happenes in G2

centrioles replaced; more organelles synthesized; enzymes for division produced; final checks for DNA errors

G1 checkpoint

cell commits to cell division; checks for size, energy reserves, and DNA damage

S checkpoint

repairs DNA before division; fixes errors during DNA replication

G2 checkpoint

Checks size and protein reserves again; checks chromosomes are replicated and DNA is not damaged

M checkpoint

sees if sister chromatids are attached to spindle microtubules before going to anaphase