You are studying two traits in fruit flies: wing shape and eye color. Wings can be either bent or straight. Eyes can be either red or yellow. Straight-winged, yellow-eyed female X bent-winged, red-eyed male gave: 41 bent yellow males 38 bent red females 38 straight yellow males 43 straight red females an F1 bent-winged, red-eyed female X an F1 bent-winged, yellow-eyed male gave: 31 bent red females 10 straight red females 28 bent yellow females 11 straight yellow females 32 bent red males 9 straight red males 29 bent yellow males 10 straight yellow males Explain these results and give the genotypes of the parents in each of the crosses.

From the observation, It can be seen that the bent-winged genotype is dominant, while the straight-winged genotype is recessive. Also, for the eye colour, the traits are found on only the X chromosome. This causes the males to inherit their eye colour from their mother, since females are the source of the single X chromosomes in males (XY - male). However, the females inherit their eye colour from their father's X-chromosome. Thus, it can be determined that the eye colour, in this instance, has a cross gender mode of inheritance due to its placement on the X-chromosome.

Parent phenotype

Take: Bent-wing (B), Straight wing (s), Red eye (R) Yellow eye (Y)

Prime generation parent

Female (Straight-wing, Yellow eye) - s s Y (ss - homozygous recessive trait)

Male (Bent-wing, Red eye) - B s R (Bs - Heterozygous dominant trait)

1st generation Parent (F1)

Female (Bent-wing, Red eye) - B s R

Male (Bent-wing, Yellow eye) - B s Y