True-breeding flies with singed bristles (s) and normal wings (l) were crossed to true-breeding flies with normal bristles (s) and vestigial wings (l). all f1 offspring had normal wings and normal bristles. (note: assume that neither of these genes is x-linked.) the f1 offspring were then crossed to flies with singed bristles and vestigial wings. for the f2 offspring, what genotypes and phenotypes are possible? which f2 offspring are recombinant and which are nonrecombinant? what will be the ratios of the f2 offspring if independent assortment is taking place? how will the ratios be affected by linkage?