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Hendrina discovered a novel type of fast-growing, small, orange-flowering plant. She was interested in learning more about the genes encoding the biochemical pathway responsible for the orange pigmentation, so she mutagenized a pure-breeding population of the orange plants in the laboratory and isolated white-flowered mutants.

She discovered two different pure-breeding strains of white-flowered plants and crossed one of the mutant strains with the other. She was surprised to obtain orange-flowered heterozygotes in the ${F}_{1}$ generation.

Next, she crossed one of the ${F}_{1}$ plant strains with another and obtained the following result for the ${F}_{2}$ generation:

226 orange-flowered plants
174 white-flowered plants

What can Hendrina deduce about the relationship between the two genes associated with the two pure-breeding white-flowered plants from these data? In other words, are the two mutations in the same gene (allelic) or are they in different genes?

A

The mutations within the two pure-breeding strains of white-flowered plants are allelic, meaning that the two mutations are in the same gene.

B

The two pure-breeding strains of white-flowered plants each have a mutation in a different gene encoding a different enzyme in the same biochemical pathway.

C

The mutated gene associated with the white-flowered phenotype from one of the pure-breeding mutants is epistatic to an unlinked gene carrying the mutation associated with the white-flowered phenotype from the other pure-breeding mutant.

D

The mutation associated with the white-flowered phenotype from one of the pure-breeding mutants suppresses the mutation of a second gene associated with the white-flowered phenotype from the other pure-breeding mutant.

E

The mutation associated with the white-flowered phenotype from one of the pure-breeding mutants is both allelic and codominant with the mutation associated with the white-flowered phenotype from the other pure-breeding mutant.

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