In fruit flies, the mutant gene d causes short legs and the mutant gene pr causes purple eyes. A geneticist performs the following cross: pr d / ++ × pr d / pr d. She counts 1000 offspring and finds 391 wild type, 115 purple-eyed and normal-legged, 105 normal-eyed and short-legged, and 389 purple-eyed and short-legged. What is the map distance between the genes for leg length and eye color? b) The same geneticist then performs the following cross: vg d / ++ × vg d / vg d. She counts 1000 offspring and finds 350 wild type, 154 vestigial-winged and normal-legged, 153 normal-winged and short-legged, and 343 vestigial-winged and short-legged. What is the map distance between the genes for leg length and wing type? c) The recombination frequency for the gene for eye color and the gene for wing type is 8.7%. What is the map distance between these two genes? Draw a chromosome map showing the relative distances between all three linked genes studied in Part B.

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