Science / Biology / Chromatid: Generally refers to a strand of a replicated chromosome; consists of DNA and protein.

Sister Chromatids

Science / Biology / Sister Chromatids: Chromatids joined by a common centromere and carrying identical genetic information (unless crossing-over has occurred). MORE

Fragile Sites

Science / Genetics / Fragile Sites: A non-staining gap of variable width that usually involves both chromatids and is always at exactly the same point on a specific chromosome derived from an individual or kindred. MORE


Science / Biology / Tetrad: The four chromatids in each cluster during synapsis; formed by the two sister chromatids in each of the two homologous chromosomes. MORE


Science / Biology / Recombination: A way in which meiosis produces new combinations of genetic information. During synapsis, chromatids may exchange parts with other chromatids, leading to a physical exchange of chromosome parts; thus, MORE


Science / Biology / Crossing-Over: During the first meiotic prophase, the process in which part of a chromatid is physically exchanged with another chromatid to form chromosomes with new allele combinations. MORE


Science / Biology / Centromere: A specialized region on each chromatid to which kinetochores and sister chromatids attach. MORE