- Each of the two strands formed by longitudinal duplication of a chromosome that becomes visible during prophase of mitosis or meiosis; the two chromatids are joined by the still undivided centromere; after the centromere has divided at metaphase and the two chromatids have separated, each c. becomes a chromosome. [G. chroma, color, + -id (2),]
* * *chro·ma·tid 'krō-mə-təd n one of the usu. paired and parallel strands of a duplicated chromosome joined by a single centromere see CHROMONEMA
* * *n.one of the two threadlike strands formed by longitudinal division of a chromosome during mitosis and meiosis. They remain attached at the centromere. Chromatids can be seen between early prophase and metaphase in mitosis and between diplotene and the second metaphase of meiosis, after which they divide at the centromere to form daughter chromosomes.
* * *chro·ma·tid (kroґmə-tid) one of the paired daughter strands, joined at the centromere, which make up a chromosome after it has replicated, each strand containing a single DNA double helix. After division of the centromere in mitosis or meiosis, each one of the pair becomes a separate chromosome.
Medical dictionary. 2011.