Question

if 72 out of 200 individuals express the recessive phenotype, what percentage will be heterozygous? 48% 72% 24% 12.6%

Explanation:

Step1: Calculate the frequency of recessive phenotype ($q^{2}$)

The frequency of recessive phenotype is $\frac{72}{200}=0.36$. So, $q^{2} = 0.36$.

Step2: Find the value of $q$

Since $q^{2}=0.36$, then $q=\sqrt{0.36}=0.6$.

Step3: Find the value of $p$

Using the Hardy - Weinberg equation $p + q=1$. Substituting $q = 0.6$, we get $p=1 - 0.6=0.4$.

Step4: Calculate the frequency of heterozygotes ($2pq$)

Substitute $p = 0.4$ and $q = 0.6$ into $2pq$. So, $2pq=2\times0.4\times0.6 = 0.48$.

Answer:

$48\%$