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.

Expert Solution

gladiator answered 3 months ago

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