In a cross in which there is a mean crossover frequency of 0.9 between two marker loci,the recombinant frequency for those loci will be:
A)5%.
B)10%.
C)30%.
D)45%.
E)90%.

Question

Quizplus · Accepted Answer

The recombinant frequency can be calculated by subtracting the non-recombinant frequency from 100%. The non-recombinant frequency can be estimated by subtracting the crossover frequency from 50% (as the two marker loci are located on different chromosomes and can independently assort during meiosis).

Non-recombinant frequency = 50% - 0.9 = 49.1%
Recombinant frequency = 100% - 49.1% = 50.9%

Therefore, the recombinant frequency for those loci will be approximately 51% (rounded to the nearest integer), which is closest to choice C (30%).

In a Cross in Which There Is a Mean Crossover