If the frequncy of recessive allele in a population is `0.3` then calculate the prercentage of heterozygotes in a population.

Options

A. 0.09
B. 0.42
C. 0.49
D. 0.91

Answer

To solve the problem of calculating the percentage of heterozygotes in a population given the frequency of the recessive allele, we can follow these steps:

### Step-by-step Solution:

1. **Identify the given information**:
- Frequency of the recessive allele (q) = 0.3

2. **Use the Hardy-Weinberg principle**:
- According to the Hardy-Weinberg equilibrium, the sum of the frequencies of the dominant allele (p) and the recessive allele (q) is equal to 1.
- This can be expressed as:
\[ p + q = 1 \]

3. **Calculate the frequency of the dominant allele (p)**:
- Since we know q = 0.3, we can find p:
\[ p = 1 - q = 1 - 0.3 = 0.7 \]

4. **Calculate the frequency of heterozygotes (2pq)**:
- The frequency of heterozygotes in the population can be calculated using the formula:
\[ 2pq \]
- Substituting the values of p and q:
\[ 2pq = 2 \times (0.7) \times (0.3) = 2 \times 0.21 = 0.42 \]

5. **Convert the frequency to percentage**:
- To express the frequency of heterozygotes as a percentage, multiply by 100:
\[ 0.42 \times 100 = 42\% \]

### Final Answer:
The percentage of heterozygotes in the population is **42%**.

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