im studying for finals and the one question is why are the sex chromosomes considered nohomologous?? (just incase nonhomologous means basically not the same, like differences in alleles/traits) help!
2007-01-20 07:40:57 · 2 answers · asked by ♥♫☺bee yourself☺♫♥ 3 in Education & Reference ➔ Homework Help
Sex chromosomes are nonhomologous because the X and Y chromosomes don't match - they don't have genes for the same traits. The X chromosome is way bigger, too.
2007-01-20 08:04:11 · answer #1 · answered by ecolink 7 · 0⤊ 0⤋
Most human chromosomes come in "homologous" pairs, meaning there are two alleles for every gene on the chromosomes, one on each strand of DNA. These are called autosomal chromosomes.
Sex chromosomes, on the other hand, don't always come in matching pairs. Women have two X chromosomes so they match up exactly, but men have an X and a Y, which don't match up. The Y is much shorter and contains only a few alleles.
2007-01-20 17:27:09 · answer #2 · answered by timemutt 2 · 0⤊ 0⤋