Question

p² individuals with two dominant alleles
2pq individuals with one dominant and one recessive allele
q² individuals with two recessive alleles

problem 1

in a population of 500 frogs, 20 show a recessive trait for skin color. assuming the trait is determined by a single gene with dominant and recessive alleles, calculate:

• the frequency of the recessive allele (q)
• the frequency of the dominant allele (p)

Explanation:

Step1: Calculate $q^2$ (recessive genotype freq)

$\frac{20}{500} = 0.04$

Step2: Solve for recessive allele $q$

$q = \sqrt{0.04} = 0.2$

Step3: Solve for dominant allele $p$

$p = 1 - q = 1 - 0.2 = 0.8$

Answer:

• The frequency of the recessive allele (q): $0.2$
• The frequency of the dominant allele (p): $0.8$