Some people crossed a mutant parental ?y with a wild—type parental ?y. An example of this is sepia females x wildtype males. All of the F1 offspring were wild—type. When the F1 offspring were crossed, the F2 included: 29 wild—type flies (14 males, 15 females) 11 sepia ?ies (4 male, 7 female) Calculate the offspring ratio of wild—type: sepia. Is this what you would have expected? Explain your reasoning. The Offspring Ratio of Wild-Type to Sepia in a Mutant Parental Fly x Wild-Type Parental Fly Cross

The Offspring Ratio of Wild-Type to Sepia in a Mutant Parental Fly x Wild-Type Parental Fly Cross

When a mutant parental fly (sepia females) is crossed with a wild-type parental fly (wildtype males), a 1:1 offspring ratio of wild-type to sepia is expected. In the case of this cross, the F2 offspring included 29 wild-type flies (14 males, 15 females) and 11 sepia flies (4 males, 7 females). This results in a final offspring ratio of wild-type to sepia of 2.63:1, which is slightly higher than the expected 1:1 ratio. The higher-than-expected ratio in this cross can be explained by the phenomenon of genetic dominance. In this cross, the wild-type allele is dominant over the sepia allele, meaning that only one wild-type allele is needed for the wild-type phenotype to be expressed (Bogdanove, 2018). As a result, the sepia phenotype can only be expressed if both alleles are sepia. This explains why there were more wild-type flies than sepia flies in the F2 offspring. Overall, the offspring ratio of wild-type to sepia in this cross is higher than expected, but this can be explained by the genetic dominance of the wild-type allele. This phenomenon is seen across many different genetic crosses, and serves as an important reminder of the importance of understanding the fundamentals of genetic inheritance (Khan, 2021). Cont….