If in a population, frequency of organisms of recessive trait is 25% then calculate the frequency of recessive allele :

Options

A. 0.25
B. 0.5
C. 0.75
D. 0.05

Answer

To solve the problem of calculating the frequency of the recessive allele given that the frequency of organisms with the recessive trait is 25%, we can use the Hardy-Weinberg principle. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the given information
We know that the frequency of organisms with the recessive trait (let's denote it as 'q²') is 25%. This means:
\[ q² = 0.25 \]

### Step 2: Calculate the frequency of the recessive allele (q)
To find the frequency of the recessive allele (q), we need to take the square root of the frequency of the recessive phenotype:
\[ q = \sqrt{q²} = \sqrt{0.25} = 0.5 \]

### Step 3: Conclusion
The frequency of the recessive allele (q) is 0.5 or 50%.

### Final Answer
The frequency of the recessive allele is **0.5** or **50%**.

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