Question

In fruit flies, red eyes (pr _) are dominant to purple eyes (prpr) and normal wings (vg _) are dominant to vestigial wings (vgvg). The genes are located on the same chromosome. A pure breeding red-eyed fly with vestigial wings was crossed with a pure-breeding purple-eyed fly with normal wings. All of the F1 progeny had a WT phenotype. What represents the arrangement of alleles on the F1's chromosome?

Answer 1

F1) 100% wild type, Pr Vg / pr vg

-----Pr--------Vg------

-----pr---------vg------

Step-by-step explanation:

Available data:

• Two genes located on the same chromosome
• red eyes (Pr _) are dominant to purple eyes (prpr)
• normal wings (Vg _) are dominant to vestigial wings (vgvg)

Cross: A pure breeding red-eyed fly and vestigial wings with a pure-breeding purple-eyed fly and normal wings

Parentals) Pr vg / Pr vg x pr Vg / pr Vg

Gametes) ----Pr-------vg---- ----pr-------Vg----

----Pr-------vg---- ----pr--------Vg----

F1) 100% wild type, Pr Vg / pr vg

-----Pr--------Vg------

-----pr---------vg------