Question

In fruit flies, the allele for vestigial wings is recessive to the allele for normal wings. In a generation of fruit flies, 18 males and 15 females with vestigial wings are produced, and 43 males and 44 females with normal wings are produced. Which of the following is the best conclusion you can make about the parents of this generation?

Answer 1

In Mendelian genetics one of the fundamental laws is The Law of Independent Assortment. The law states that parental traits are passed independently from parent to child. The recessive trait, vestigial wings, occurs in an approximate phenotypic ratio of 1:3. In a monohybrid cross of heterozygous (Rr) parents the expected phenotypic ratio correlates with the given 1:3 result therefore I can conclude that the parents are both heterogeneous (Rr) for vestigial wings. Normal Wings = R, Vestigial Wings = r (Parent 1) Rr * Rr (Parent 2) R * R = RR = Normal Wings (Child 1) R * r = Rr = Normal WIngs (Child 2) r * R = Rr = Normal Wings (Child 3) r*r = rr = Vestigial Wings (Child 4) 1 Vestigial Wings : 3 Normal Wings

Answer 2

What he meant was both parents are hetero