There are two alleles `(A_(1)&A_(2))` out of which one `(A_(1))` has nil abundance in a population then the abundance of second allele `(A_(2))` is :-

Options

A. `0.25`
B. `1.00`
C. `0.40`
D. `0.50`

Answer

To solve the question regarding the abundance of the second allele \( A_2 \) when the first allele \( A_1 \) has nil abundance in a population, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Allele Abundance**: We have two alleles, \( A_1 \) and \( A_2 \). The problem states that the abundance of allele \( A_1 \) is nil, which means its frequency is 0 in the population.

2. **Using the Hardy-Weinberg Principle**: According to the Hardy-Weinberg principle, the sum of the frequencies of all alleles in a population must equal 1. This can be expressed as:
\[ p + q = 1 \]
where \( p \) is the frequency of allele \( A_1 \) and \( q \) is the frequency of allele \( A_2 \).

3. **Substituting the Known Value**: Since we know that the frequency of allele \( A_1 \) (denoted as \( p \)) is 0, we can substitute this value into the equation:
\[ 0 + q = 1 \]

4. **Solving for the Frequency of \( A_2 \)**: From the equation, we can solve for \( q \):
\[ q = 1 \]
This means that the frequency of allele \( A_2 \) is 1.

5. **Conclusion**: Therefore, the abundance of the second allele \( A_2 \) in the population is 1.

### Final Answer:
The abundance of allele \( A_2 \) is 1.

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