Question

Thedrosophila alleles for purple eyes (instead of red) and dumpy wings(instead of normal) are both recessive. Gene E designates eye color(E: dominant, e: recessive), and gene D designates wing shape (D:dominant, d: recessive). You cross a pure breeding purple eyes,normal winged fly to a true breeding red eyed, dumpy winged fly.

11. You cross these F1 offspring to flies that are purebreeding for purple eyes and dumpy wings. You get 200 offspring. 45are purple eyes and dumpy winged, 43 are red eyed and normalwinged, 63 are purple eyed and normal winged, and 49 are red eyedand dumpy winged. You think that these two genes could be ondifferent chromosomes but your friend tells you that he thinks theyare linked and that they are close enough to each other to have afrequency of recombinant a of 0.38. If you are correct and they areon different chromosomes, how many purple eyes, normal winged flieswould you ideally expect out of your 200 offspring?

12. If your friend is correct and the genes are linked withfrequency of recombinant a of 0.38 how many purple eyed, normalwinged flies would you expect?

13. Calculate the chi squared value of the genes are ondifferent chromosomes.

14. Calculate the chi squared value if your friend iscorrect.

15. Who is more likely to be correct?