Editing Karyotype (section)

===Copy number===
[[File:Animal cell cycle-en.svg|thumb|The [[cell cycle]]]]
Schematic karyograms generally display a DNA copy number corresponding to the [[G0 phase|G<sub>0</sub> phase]] of the cellular state (outside of the replicative [[cell cycle]]) which is the most common state of cells. The schematic karyogram in this section also shows this state. In this state (as well as during the G<sub>1</sub> phase of the [[cell cycle]]), each cell has two autosomal chromosomes of each kind (designated 2n), where each chromosome has one copy of each [[Locus (genetics)|locus]], making a total copy number of two for each locus (2c). At top center in the schematic karyogram, it also shows the chromosome 3 pair after having undergone [[DNA synthesis]], occurring in the [[S phase]] (annotated as S) of the cell cycle. This interval includes the [[G2 phase|G<sub>2</sub> phase]] and [[metaphase]] (annotated as "Meta."). During this interval, there is still 2n, but each chromosome will have two copies of each locus, wherein each [[sister chromatid]] (chromosome arm) is connected at the centromere, for a total of 4c.<ref name="pmid30202427">{{cite journal| author=Gomes CJ, Harman MW, Centuori SM, Wolgemuth CW, Martinez JD| title=Measuring DNA content in live cells by fluorescence microscopy. | journal=Cell Div | year= 2018 | volume= 13 | issue=  | pages= 6 | pmid=30202427 | doi=10.1186/s13008-018-0039-z | pmc=6123973 | doi-access=free }} </ref> The chromosomes on micrographic karyograms are in this state as well, because they are generally micrographed in metaphase, but during this phase the two copies of each chromosome are so close to each other that they appear as one unless the image resolution is high enough to distinguish them. In reality, during the G<sub>0</sub> and G<sub>1</sub> phases, nuclear DNA is dispersed as [[chromatin]] and does not show visually distinguishable chromosomes even on micrography.

The copy number of the [[Human mitochondrial genetics|human mitochondrial genome]] per human cell varies from 0 (erythrocytes)<ref name="pmid3178814">{{cite journal| author=Shuster RC, Rubenstein AJ, Wallace DC| title=Mitochondrial DNA in anucleate human blood cells. | journal=Biochem Biophys Res Commun | year= 1988 | volume= 155 | issue= 3 | pages= 1360–5 | pmid=3178814 | doi=10.1016/s0006-291x(88)81291-9 | pmc= | url=https://pubmed.ncbi.nlm.nih.gov/3178814  }} </ref> up to 1,500,000 ([[Egg cell|oocytes]]), mainly depending on the number of mitochondria per cell.<ref name="pmid28721182">{{cite journal| author=Zhang D, Keilty D, Zhang ZF, Chian RC| title=Mitochondria in oocyte aging: current understanding. | journal=Facts Views Vis Obgyn | year= 2017 | volume= 9 | issue= 1 | pages= 29–38 | pmid=28721182 | doi= | pmc=5506767 }} </ref>