Part 3: crossing tail-feather length and feather color cross a p generation, llbb with llbb. assume the following f1 generation: llbb: 480 llbb: 20 llbb: 20 llbb: 480 (score for question 1: of 2 points) 1. which offspring are not the recombinant offspring in this cross?type your answer here. (score for question 2: of 2 points) 2. how far apart are l and b?type your answer here.

Q: 1.Which offspring are not the recombinant offspring in this cross?

It is mentioned in the question that we are crossing Tail-Feather Length and Feather Color with short feather length and recessive feather color organisms.

P1:                                           LlBb X llbb

Gametes:                              LB: Lb: lB: lb :      lb

Offspring:

So as we see that perntal combinations are LlBb  and llbb which means 480 + 480 organisms are just like parents while Llbb: 20  and llBb: 20  (20 +20=40) are recombinants.

It means that number of recombinants are 40.

Q2:  How far apart are L and B?

To answer this question we will use a formula:

The distance between L and B = Total number of recombinant types/  total number of offspring X 100

It means that distance between L and B=  40/1000 X 100

                                                                  = 4

It means L and B are 4 units apart because they make up 4 % of the total recombinant types. you just saw how we did it.

Hope it help! :)