13) In Drosophila, assume that the gene for scute bristles (s) is located at map position 0.0 and that the gene for ruby eyes (r) is at position 15.0. Both genes are located on the X chromosome and are recessive to their wild-type alleles. A cross is made between scute-bristled females and ruby-eyed males. Phenotypically wild F1 females were then mated to homozygous double mutant males, and 1000 offspring were produced. Give the phenotypes and frequencies expected.
14) Assume that investigators crossed a strain of flies carrying the dominant eye mutation Lobe on the second chromosome with a strain homozygous for the second chromosome recessive mutations smooth abdomen and straw body. The F1 Lobe females were then backcrossed with homozygous smooth abdomen, straw body males, and the following phenotypes were observed:
smooth abdomen, straw body 820
Lobe 780
smooth abdomen, Lobe 42
straw body 58
smooth abdomen 148
Lobe, straw body 152
(a) Give the gene order and map units between these three loci.
(b) What is the coefficient of coincidence?
I need it explained how to get the answer not just the answers I have those already and it doesn't help me learn how to solve these problems.
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