3 point test cross

Question 1

The correct gene order

Answer 1

The double crossing

Question 2

Parental types

Answer 2

The most frequent and then compare it to the one that is the least frequent. The 2 genes that are least abundant provides a double crossing comparison to the P-generation. The gene you have to invert in the P-generation to get the recombinants, is the gene that belong in the middle.

Question 3

Map distances

Answer 3

After finding the gene in the middle rewrite the sequences in the correct order. To get the distances do single cross over to the genes by drawing and take the number of recombinations and divide them by total.

Do not forget to take into account the double crossovers in the calculations.

Question 4

RF?

Answer 4

Percent recombinations in gametes

Question 5

The total distance

Answer 5

Add the distances to the gene in the middle together and then the double crossovers twice,