Sarah J. answered • 10/05/21
Tutor
New to Wyzant
Human Molecular Genetics Instructor
Hello! I think I can help you with this. It seems like what you are referencing here is actually the cell cycle, a cycle in which mitosis is a singular stage (the M stage)!
The stages of the cells cycle are as follows:
- G1: each cell contains one diploid copy of the genome (aka 46 chromosomes)
- S phase: the stage where DNA Synthesis occurs - each chromosome is duplicated and now consists of 2 sister chromatids, which are held together at the centromere
- G2: a brief phase between S-phase and mitosis where the cell finishes doubling in size - the cell now contains two copies of the diploid genome (92 chromosomes)
- M phase (mitosis): mitosis is the phase of the cell cycle in which the cell splits into two identical diploid cells (each containing 46 chromosomes) following these stages:
- Prophase: condensation of the chromosomes, formation of the mitotic spindle, formation of centrosomes (prefix pro- means "before"; aka first step!)
- Prometaphase: nuclear membrane dissolves, chromosomes disperse throughout the cell and attach to microtubules of the mitotic spindle
- Metaphase: chromosomes line up in the middle along the equatorial plane
- Anaphase: Chromosomes separate (away) at the centromere - sister chromatids of each chromosome now become independent daughter chromosomes and move to opposite poles of the cell
- Telophase: nuclear membrane begins to reform around each of the two new daughter nuclei and chromosomes begin to de-condense
- Cell division is completed once the cytoplasm is cleaved during the cytokinesis process.
- G0: a phase entered by cells that are dividing more slowly - cells enter this resting phase after G1. During this time the cell is resting and not actively preparing to divide
- G1, S, and G2 = interphase
I hope this helps!
