A line of Drosophila melanogaster with ebony body and sepia eyes (line A) is crossed to a line with tan body and red eyes (line B). The F1 are all tan-bodied, redeyed.
a) (one point) What proportion of gametes produced by the F1 have the dominant allele for both loci? What proportion of the gametes produced by line B have the dominant allele for both loci?
Next, imagine that An F1 female is crossed to a male from line A.
If 1000 offspring were scored for both characters, what number of offspring would be expected to have each of the four phenotypes (assuming no linkage)? List them below.
Now imagine that the following data were actually collected from the cross above:
Body Eyes
Tan normal 491
Tan sepia 9
Ebony normal 8
Ebony sepia 492
b) (one point) Are the loci linked? If so, how many map units are they apart ? Do a ?2 test and show your work below. Diagram this cross.
