BIOL 321 Chapter Notes - Chapter 6: G Banding, Congenital Disorder, Gamete
Document Summary
Chromosomes (human) exist in pairs, with most cells having 23 homologous pairs, or 46 total chromosomes. One member of each homologous pair is contributed by each parent. These contributed cells have 23 individual chromosomes, which is the haploid (n) number of chromosomes. Chromosomes have 4 important parts: centromere a region of a chromosome to which spindle fibers attach during cell division. The location of a centromere gives a chromosome its characteristic shape: telomere short repeated dna sequences located at each end of chromosomes, prevent the chromosomes from sticking to each other. Telomeres shortening over time may be responsible for aging: short arm (p arm, long arm (q arm) Metacentric describes a chromosome that has a centrally placed centromere. Submetacentric describes a chromosome whose centromere is placed closer to one end than the other. Aerocentric describes a chromosome whose centromere is placed very close to, but not at, one end.
