Sister Chromatids

Sister chromatids are two identical copies of a chromatid. Compare sister chromatids to homologous chromosomes, which are the two different copies of the same chromosome that diploid organisms (like humans) inherit, one from each parent. In other words, sister chromatids contain the same genes and same alleles, and homologous chromosomes contain the same genes but two copies of alleles, each of which might or might not be the same as each other. A full set of sister chromatids is created during the S subphase of interphase, when all the DNA in a cell is replicated. Identical chromatid pairs are separated into two different cells during mitosis,

There is evidence that, in some species, sister chromatids are the preferred template for DNA repair. Sister chromatid cohesion is essential for the correct distribution of genetic information between daughter cells and the repair of damaged chromosomes. Defects in this process may lead to aneuploidy and cancer, especially when checkpoints fail to detect DNA damage or when incorrectly attached mitotic spindles do function properly.

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Other articles related to "sister chromatids, chromatids, sister chromatid":

Chiasma (genetics)
... A chiasma (plural chiasmata), in genetics, is thought to be the point where two homologous non-sister chromatids exchange genetic material during chromosomal ... When each tetrad, which is composed of two pairs of sister chromatids, begins to split, the only points of contact are at the chiasmata ... A bivalent refers to the two homologous chromosomes (4 chromatids) ...
Sister Chromatids - See Also
... Biorientation Meiosis Sister chromatid exchange. ...
Meiome - Phases - Meiosis II
... the two haploid cells (23 chromosomes, N * each of the chromosomes consisting of two sister chromatids) produced in meiosis I ... envelope again as well as the shortening and thickening of the chromatids ... attached to the kinetochores to pull the sister chromatids apart ...
Separase - Function
... Stable cohesion between sister chromatids before anaphase and their timely separation during anaphase are critical for cell division and chromosome inheritance ... In vertebrates, sister chromatid cohesion is released in 2 steps via distinct mechanisms ... which initiates the final separation of sister chromatids ...
Meiome - Process
... becomes a complex of two identical sister chromatids ... The identical sister chromatids have not yet condensed into the densely packaged chromosomes visible with the light microscope ... of separating the pairs of homologous chromosome, each made up of two sister chromatids, into two cells ...

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