Questions 9-15 are related. The drosophila alleles for purple eyes (instead of r
ID: 70532 • Letter: Q
Question
Questions 9-15 are related. The drosophila 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 eyed, normal winged fly to a true breeding red eyed, dumpy winged fly.
9. What are the genotypes of the parental flies? (select all that apply)
eedd
10. What would you expect the offspring (F1) phenotypes to be?
None of the above
11. You cross these F1 offspring to flies that are pure breeding for purple eyes and dumpy wings. You get 200 offspring. 45 are purple eyed and dumpy winged, 43 are red eyed and normal winged, 63 are purple eyed and normal winged, and 49 are red eyed and dumpy winged. You think that these two genes could be on different chromosomes but your friend tells you that he thinks they are linked and that they are close enough to each other to have a frequency of recombinants of 0.38. If you are correct and they are on different chromosomes, how many purple eyed, normal winged flies would you ideally expect out of your 200 offspring? Your answer should be a whole number.
12. If your friend is correct and the genes are linked with frequency of recombinants of 0.38 how many purple eyed, normal winged flies would you expect? Your answer should be a whole number
EEDDExplanation / Answer
9). Pure breeding plants or true breeding plants are those whose alleles are homozygous for the trait. The genotype of a pure breeding purple eyed (recessive), normal winged (dominant) fly is eeDD. The genotype of a true breeding red eyed (EE), dumpy winged fly (dd) is EEdd.
Thus, the correct options are, eeDD and EEdd.
10). Cross between these two will have the offspring with the following genotypes.
eeDD* EEdd = EeDd (100% red eyed, normal winged).
Thus, the correct option is b. All red eyed, normal winged.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.