A chromatid's one among the two identical copies of DNA making up a replicated chromosome, which are joined at their centromeres, for the process of cell division (mitosis or meiosis). The term's used so long as the centromeres remain in contact. When they separate (during anaphase of mitosis and anaphase 2 of meiosis), the strands are called daughter-chromosomes. In other words, a chromatid's "one-half of a replicated chromosome". It shouldn't be confused with the ploidy of an organism, which'… (More on Chromatid)