In Drosophila, the autosomal recessive pr and cn mutations cause brown and bright-red eyes, respectively (wild-type flies have brick-red eyes) .Flies who are homozygous recessive at both pr and cn have orange eyes.A female who has wild-type eyes is crossed to an orange-eyed male.Their progeny have the following distribution of eye colors:
$\begin{array} { | l | r | } \hline \text { wild-type } & \text { 8 } \\\hline \text { brown } & 241 \\\hline \text { briphit-red } & 239 \\\hline \text { orarnge } & \underline{12} \\\hline & 500 \\\hline\end{array}$
-The mother of these progeny resulted from a cross between two flies from true-breeding lines.What are the genotypes of these two lines?

Question

In Drosophila, the autosomal recessive pr and cn mutations cause brown and bright-red eyes, respectively (wild-type flies have brick-red eyes) .Flies who are homozygous recessive at both pr and cn have orange eyes.A female who has wild-type eyes is crossed to an orange-eyed male.Their progeny have the following distribution of eye colors:

\begin{array} { | l | r | } \hline \text { wild-type } & \text { 8 } \\\hline \text { brown } & 241 \\\hline \text { briphit-red } & 239 \\\hline \text { orarnge } & \underline{12} \\\hline & 500 \\\hline\end{array}

-The mother of these progeny resulted from a cross between two flies from true-breeding lines.What are the genotypes of these two lines?

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The Answer of In Drosophila, the autosomal recessive pr and cn mutations cause brown and bright-red eyes, respectively (wild-type flies have brick-red eyes).Flies who are homozygous recessive at both pr and cn have orange eyes.A female who has wild-type eyes is crossed to an orange-eyed male.Their progeny have the following distribution of eye colors: $$\begin{array} { | l | r | } \hline \text { wild-type } & \text { 8 } \ \hline \text { brown } & 241 \ \hline \text { briphit-red } & 239 \ \hline \text { orarnge } & \underline{12} \ \hline & 500 \ \hline \end{array}$$ -The mother of these progeny resulted from a cross between two flies from true-breeding lines.What are the genotypes of these two lines? A)pr cn⁺ / pr cn⁺ and pr⁺ cn / pr⁺ cn B)pr⁺ cn⁺ / pr⁺ cn⁺ and pr cn / pr cn C)pr⁺ cn⁺ / pr cn and pr cn / pr cn D)pr⁺ cn / pr cn and pr cn⁺ / pr cn E)More than one of these could be true.

In Drosophila, the Autosomal Recessive Pr and Cn Mutations Cause