Bio Question from cliffs AP

[jvss123]

Advertisement - Members don't see this ad

Four genes, J,K,L, and M, reside on the same chromosome. Given that the crossover frequency between K and J is 3, between K and L is 8, between J and M is 12, and between L and M is 7, what is the order of the genes on the chromosome?

1) JKLM
2) JKML
3) KJLM
4) KJML
5) KLJM

I dont understand their explanation... can some plz provide me with a detailed explanation on how to solve for this. thanks 😳

 

[299678]

Four genes, J,K,L, and M, reside on the same chromosome. Given that the crossover frequency between K and J is 3, between K and L is 8, between J and M is 12, and between L and M is 7, what is the order of the genes on the chromosome?

1) JKLM
2) JKML
3) KJLM
4) KJML
5) KLJM

I dont understand their explanation... can some plz provide me with a detailed explanation on how to solve for this. thanks 😳

3) KJLM Recombination frequency is directly related with it's distance between linked genes, so if there is 10 map unit distance, we can possibly assume their gene's location relatively. K____3______J ____5_____L ____7_____M so JL = 5 map units, 5+3 = 8 units which make sense.