Final answer:
The recombination frequency is calculated by dividing the number of recombinant offspring by the total number of offspring, then it can be expressed as a percentage or in centimorgans (cM), with 1% recombination frequency equaling 1 cM.
Step-by-step explanation:
The recombination frequency is a method used by geneticists to determine the genetic distance between two linked genes on a chromosome.
It is calculated by taking the number of recombinant offspring (those with nonparental genotypes) and dividing it by the total number of offspring observed.
For example, if we consider the cross between AaBb and aabb, where we observed 50 recombinant offspring out of 1000 total offspring, the recombination frequency would be 50/1000 or 0.05.
This value, expressed as a percentage, gives us a recombination frequency of 5%. In genetic mapping, this frequency can be translated into map units or centimorgans (cM), with 1% recombination frequency being equivalent to 1 cM.
Therefore, if the recombination frequency is 0.05 or 5%, the two genes would be considered 5 cM apart on a genetic map.