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Linked Genes

APBIO-JTNEWX

Fruit flies homozygous for wild-type body (B) and wild-type wings (V) were crossed with homozygous recessive black bodies (b) and vestigial-winged flies (v). The F1 offspring were then test-crossed with flies homozygous recessive for both body color and wing.

The following results were obtained in the F2 generation:

Wild-type body and wild-type wings 350
Wild-type body and vestigial wings 30
Black body and wild-type wings 45
Black body and vestigial wings 275

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Based on these results, which of the following is the BEST conclusion?

A

The genes for body color and wing type are on separate chromosomes.

B

The genes for body color and wing types are on the same chromosomes and are 10.7 map units apart.

C

The genes for body color and wing types are linked and are 12 map units apart.

D

The genes for body color and wing types are linked on the same chromosome due to crossing over.