Question

Оперенность ног у кур наследуется как доминантный признак.Определите(%) долю птиц с оперенными ногами в популяции, где частота аллеля оперенности ног составляет 70% и сохраняется равновесие Харди-Вайнберга.

Answer 1

50 %             ...................

Answer 2

Inheritance of Feathered Legs in Chickens

The inheritance of feathered legs in chickens is considered a dominant trait. This means that if a chicken inherits at least one copy of the allele for feathered legs, it will exhibit the trait. To determine the proportion of birds with feathered legs in a population, we can use the Hardy-Weinberg equilibrium equation.

Hardy-Weinberg Equilibrium

The Hardy-Weinberg equilibrium is a principle in population genetics that describes the relationship between allele frequencies and genotype frequencies in a population. According to this principle, if certain conditions are met, the allele and genotype frequencies in a population will remain constant from generation to generation.

The equation for the Hardy-Weinberg equilibrium is:

p^2 + 2pq + q^2 = 1

Where: - p^2 represents the frequency of the homozygous dominant genotype (AA) - 2pq represents the frequency of the heterozygous genotype (Aa) - q^2 represents the frequency of the homozygous recessive genotype (aa) - p represents the frequency of the dominant allele (A) - q represents the frequency of the recessive allele (a)

Applying the Hardy-Weinberg Equilibrium

In this case, we are given that the frequency of the allele for feathered legs (A) is 70%. Let's assume that the frequency of the recessive allele (a) is 30% since there are only two alleles in this case.

Using the Hardy-Weinberg equation, we can calculate the expected frequencies of the genotypes:

p^2 + 2pq + q^2 = 1

Substituting the given values:

(0.7)^2 + 2(0.7)(0.3) + (0.3)^2 = 1

Simplifying the equation:

0.49 + 0.42 + 0.09 = 1

0.91 = 1

The sum of the expected genotype frequencies is equal to 1, which confirms that the equation is balanced.

Proportion of Birds with Feathered Legs

To determine the proportion of birds with feathered legs in the population, we can use the frequency of the homozygous dominant genotype (AA) and the frequency of the heterozygous genotype (Aa).

In this case, the frequency of the homozygous dominant genotype (AA) is p^2 = (0.7)^2 = 0.49.

The frequency of the heterozygous genotype (Aa) is 2pq = 2(0.7)(0.3) = 0.42.

Therefore, the proportion of birds with feathered legs in the population is 0.49 + 0.42 = 0.91, or 91%.

Conclusion

Based on the given information and assuming the Hardy-Weinberg equilibrium, the proportion of birds with feathered legs in the population, where the frequency of the allele for feathered legs is 70%, is approximately 91%.