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In Drosophila , a recessive autosomal allele, ebony (e) produces a black body colour when homozygous....

In Drosophila , a recessive autosomal allele, ebony (e) produces a black body colour when homozygous. Another recessive autosomal allele, black (b) also produces a black body colour when homozygous. Wild type flies are grey.  Flies with genotypes e/e b+/-, e+/- b/b, and e/e  b/b  show identical colour phenotype.

If e/e  b+/b+ ebony flies are crossed with e+/e+ b/b black flies  than;

c) What phenotypic ratios would be observed from the crosses F1 x true-breeding ebony, and F1 x true-breeding black?

d) What would be the effect on the F2 if the F1 were also heterozygous at a suppressor locus (su-e) that could reverse the effect of the ebony mutation in su-e homozygotes.

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