For the sake of this genetics problem,consider that right-handedness (RR,Rr)is dominant to left-handedness (rr).A teacher surveys her class of 24 students and finds that six (one-fourth,or 0.25)are left-handed.How many of the remaining right-handed students are likely to be carriers for a left-handedness gene?

Question

Quizplus · Accepted Answer

We know that the frequency of left-handedness (rr) in the class is 0.25 or q2. Therefore, q (frequency of r allele) is the square root of 0.25, which is 0.5. 
Using the Hardy-Weinberg equation, 2pq represents the frequency of carriers (Rr) in the population where p is the frequency of the dominant allele (R). Therefore, 
2pq = 2(0.5)(0.5) = 0.5 
This means that 0.5 or half of the remaining right-handed students are likely to be carriers for the left-handedness gene. 
So, the best choice is C.

For the Sake of This Genetics Problem,consider That Right-Handedness (RR,Rr)is