AP BIOLOGY

EVOLUTION

EVOLUTION OF A POPULATION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
A population of frogs has 37 individuals who are brown in color and 194 individuals who express the dominant green color. What is the dominant allele frequency for this population?
A
0.2
B
0.4
C
0.6
D
0.8
Explanation: 

Detailed explanation-1: -The answer should be 0.6 and you can solve the question by Solve : total 37 + 194 = 231 frogs q2 = 37 /231 = 0.16 and p2 = 194 / 231 = 0.84 q = root of 0.16 = 0.4 and p + q = 1, resulting p = 0.6 (the answer) However, I don’t understand why we don’t just root the 0.84 (p2) to get the answer for p.

Detailed explanation-2: -In the question, the genotype frequency of recessive population is (q2) = (16% or 0.16). Hence, frequency of recessive allele = q = 0.16 = 0.4. Since p+q = 1; thus the frequency of dominant allele = p = 1-q = 1-0.4 = 0.60.

Detailed explanation-3: -1 = p2 + 2pq + q2 P and q each represent the allele frequency of different alleles. The term p2 represents the frequency of the homozygous dominant genotype.

Detailed explanation-4: -In a population that is in Hardy-Weinberg equilibrium, the frequency of homozygous dominant individuals is 0.36.

Detailed explanation-5: -So, the correct answer is ‘0.64’

There is 1 question to complete.