The man and woman do not have SCA. However, each has one parent with the disorder. What are their genotypes? Then, find the chance their child has SCA

What are their genotypes? They are both heterozygous for the trait, SsFind the chance their child has SCA. There is 25% of probabilities (1/4) that their child has SCA.

Explanation:

Due to technical problems, you will find the complete explanation in the attached files

The answer would be c, white eyes are homozygous recessive. in the early 1900s, morgan conducted several experiments with vinegar  flies (drosophila). one  sample revealed an anomaly: a  white-eyed, single male fly. he attempted to breed this fly with the typical red-eyed females. the offspring were all red-eyed. using flies from this new generation (brother-sister pairs)  produced some red-eyed and a few white-eyed flies. the white-eyed were all male. in later experiments, he was able to produce white-eyed females. this proved that white eyes are not lethal to either sex (ruling out a and b). since the percentage of white eyes to red eyes is so low, white eyes are not a dominant trait. it would be a recessive trait.