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Title: Why is there only one homologous pair of chromosomes in a gamete where n=14? Post by: julia.k18 on Sep 25, 2012 Thanks!
Title: Why is there only one homologous pair of chromosomes in a gamete where n=14? Post by: juli3_jon3s on Sep 25, 2012 The n number depends completely on the organism, so n=14 must be specific to the organism you're looking at, and it isn't human. Some flies have as little as three pairs of chromosomes, while humans have 23 pairs.
We only want one of the pair of homologous chromosomes in gametes, because the gamete from the mother fuses with the father so that you regain a pair. If each gamete had the full pair, when fertilization occurred you would have twice as many chromosomes as either of your parents. Title: Why is there only one homologous pair of chromosomes in a gamete where n=14? Post by: MicroGirl on Sep 25, 2012 If this is a gamete, then there shouldn't be ANY homologous pairs. If n=14, then the organism has 2n=28. The only way it could have a PAIR of homologues is if a pair failed to separate; this would result in a zygote with 29 chromosomes- a case of aneuploidy.
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