The genetic frequency of the Aa genotype is 0.48. This result follows directly from the Hardy-Weinberg equilibrium principle applied to the given allelic frequency.

Hardy-Weinberg Basics

Hardy-Weinberg equilibrium describes a non-evolving population where allele and genotype frequencies remain constant across generations under specific assumptions like random mating and no selection. For a gene with two alleles A (frequency p=0.6) and a (frequency q=1−p=0.4), genotype frequencies are p2 (AA), 2pq (Aa), and q2 (aa), summing to 1. These frequencies predict the proportion of each genotype in the snake population.

Step-by-Step Calculation

First, determine q=1−0.6=0.4. Next, compute the heterozygous frequency: 2pq=2×0.6×0.4=0.48. Rounded to two decimal places, this is 0.48, matching equilibrium expectations for the isolated island snake population.

In population genetics, Hardy-Weinberg equilibrium helps predict genotype frequencies like Aa when the allelic frequency of A is 0.6 in an isolated snake population. This principle assumes no evolution, making it ideal for exam questions on genetic equilibrium. For CSIR NET aspirants, mastering this ensures accurate calculations for two-allele genes.

Core Formula and Assumptions

The equation p2+2pq+q2=1 defines equilibrium, where p is the frequency of A and q=1−p. Key assumptions include infinite population size, random mating, no migration, mutation, or selection—fitting the isolated island scenario. With p=0.6, q=0.4, the Aa frequency 2×0.6×0.4=0.48.

Detailed Solution for Q.94

  • Allele A frequency: p=0.6 [query].
  • Allele a frequency: q=0.4.
  • AA frequency: p2=0.36.
  • aa frequency: q2=0.16.
  • Aa frequency: 0.48 (rounded to two decimals).

No options are provided, but common distractors include p2=0.36 (AA only), q2=0.16 (aa only), or pq=0.24 (missing the 2 factor)—all incorrect for heterozygotes. Verify by summing: 0.36+0.48+0.16=1.

CSIR NET Exam Tips

  • Practice derives from allele counts or genotype data back to frequencies.
  • Tools like calculators confirm results instantly.
  • For snakes or similar cases, emphasize isolation prevents deviation.