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Rates of Crossover


In Drosophila's gene for wing shape, wild-type is dominant to arc. In another gene for body color, wild-type is dominant to black. The two genes are located on the same chromosome. A test cross was performed between a fly heterozygous for both wing shape and body color with another fly homozygous recessive for both traits. The cross resulted in the numbers of each offspring:

Number of Offspring Trait
682 Wild-Type wing
517 Wild-Type body color
89 Arc
16 Black

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How many linkage map units apart are these two genes?


0.0805 map units


92 map units


8.05 map units


It is not possible to determine from the data given.