You continue your analysis by crossing the forked and twist lines. Your results are as follows: A cross between pure lines of twisted and forked flowers. The F1 generation was twisted and forked at the same time. When these flowers were crossed with each other, twisted, forked, and both twisted and forked flowers were obtained. Which of the following statements best explains the outcome of this cross? A. The forked mutation and the twist mutation are codominant alleles of the same locus. B. The forked mutation is incompletely dominant to the twist mutation. C. The twist mutation is incompletely dominant to the forked mutation. D. The forked mutation is epistatic to the twist mutation. E. The twist mutation is epistatic to the forked mutation.

A. The forked mutation and the twist mutation are codominant alleles of the same locus.

Explanation:

The question involves a single gene that codes for shape of flowers. According to the question, the F1 offsprings, after crossing pure lines, were both twisted and forked at the same time. After self-crossing the F1 offsprings, a twisted, forked and both forked and twisted offsprings were produced.

This depicts a non-mendelian genetic inheritance called CODOMINANCE. This is a genetic scenario whereby the alleles are neither dominant nor recessive to one another, instead, they are both expressed simultaneously. Here, the alleles for fork shape and twisted shape were neither dominant nor recessive to one another, but were phenotypically expressed together in the heterozygous offspring. Hence, the forklined and twisted alleles are said to be CODOMINANT.