Title: Genetics Post by: Sara on Oct 5, 2010 HELP Needed, not sure where to start with these questions.
The scarlet gene of the fruit fly Drosophila melanogaster is involved in the mechanism of eye pigmentation. A true-breeding scarlet-eyed female fly was crossed with a true-breeding red-eyed (ie wild type) male. The F1 progeny are shown in the table below. Phenotype Number Red-eyed male 162 Red-eyed female 179 1. What can be concluded about the relationship between the mutant allele of the scarlet gene (symbol st) and its wild type partner (symbol st+) from this result? 2. Is the scarlet gene sex linked? Explain the basis of your answer. 3. In the spaces below, write out the genotypes of the male and female parents and their F1 progeny with respect to the scarlet gene. Female parent: Male parent: F1 progeny: Title: Re: Genetics Post by: bio_man on Oct 5, 2010 1. It looks like there is a 50/50 chance of being either or. Likely, both parents are heterozygous.
2. I believe it is X linked, so it is sex-linked. I say this because you only have two phenotypes similar to how when a male mates with a female, you have the possibility of having an offspring that is either male or female. 3. XSt+ Y XSt XSt+XSt XStY XSt XSt+XSt XStY |