Home > B. Cellular pathology > Chromosomes > chromatid
chromatid
Monday 17 October 2005
Definition: Chromatid are individual daughter-chromosomes (strands) into which each chromosome is divided in all nuclear divisions. The term chromatid is used so long as the daughter centromeres remain in contact with one another. As soon as they separate (anaphase of mitosis and anaphase 2 of meiosis), the expression daughter-chromosome is substituted for chromatid.
The term which McClung (1900) proposed for each of the four threads making up a chromosome-pair at meiosis (Gk. chroma, colour; for the derivation of ’-id’, see diploid).
The use of the term was subsequently extended to mitosis, and is now applied to the individual daughter-chromosomes (strand) into which each chromosome is divided in all nuclear divisions. The term chromatid is used so long as the daughter centromeres remain in contact with one another.
As soon as they separate (anaphase of mitosis and anaphase 2 of meiosis), the expression daughter-chromosome is substituted for chromatid.
