n. the fourth stage in the first prophase of *meiosis, in which *crossing over occurs between the paired chromatids of homologous chromosomes, which then begin to separate.
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.... chromatid
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