Question

Make sure to select only one answer for each of the following questions. Mark your answers on a scantron ( hat purple 1. On a study abroad trip to Kenya, you discover the beauty of the Lilac Breasted Roller. You determine t feathers (P) are dominant over black feathers (p), and iridescence of the feathers (F) is dominant over dullness roller that was purple, and iridescent flew into your bedroom, on this. A cross with a black, dull roller produced: 11 purple, iridescent; 12 purple, dull; 10 black, dull and iridescent. You concluded that genotype of your purple, iridescent roller was: a) PPFF but you could not determine its exact genotype based b) PpFf c) ppFF d)PPff

explain as much as possible.

Answer 1

Hi,

The answer is option b) PpFf

Given, one parent is a black, dull roller. So, the genotype should be ppff (Because P and F are dominant).

And also, if we look at the ratio of offspings, it shows all the combinations are almost in the same probability.

If we cross, PPFF and ppff (one recessive parent), all the offsprings will be of dominant character only. So, the above given permutations (ratio) are not possible with offspings. And also, crossing ppFF and ppff will not give the purple irridescense roller. So, the ratio of offsprins will not match. Similarly, if we cross PPff and ppff, we will not get iridisence roller. So, the option a, c, d are ruled out of answer.

Also, if we use a punnet square for option b) PpFf and ppff, we get all the combinations of offsprings in same ratio (1:1:1:1). So, the answer is b) PpFf.