Name__________________________________ Date___________
AP Biology Period_____
Hardy-Weinberg Practice Problems
1. A population of rabbits may be brown (the dominant phenotype) or white (the recessive phenotype).
Brown rabbits have the genotype BB or Bb. White rabbits have the genotype bb. The frequency of the
BB genotype is .35.
What is the frequency of heterozygous rabbits? 0.48
What is the frequency of the B allele? 0.59
What is the frequency of the b allele? 0.41
2. A hypothetical population of 10,000 humans has 6840 individuals with the blood type AA, 2860
individuals with blood type AB and 300 individuals with the blood type BB.
What is the frequency of each genotype in this population?
AA = 0.68 / AB = 0.29 / BB = 0.03
What is the frequency of the A allele? 0.83
What is the frequency of the B allele? 0.17
If the next generation contained 25,000 individuals, how many individuals would have blood type
BB, assuming the population is in Hardy-Weinberg equilibrium? 750
3. A population of birds contains 16 animals with red tail feathers and 34 animals with blue tail feathers.
Blue tail feathers are the dominant trait.
What is the frequency of the red allele? 0.57
What is the frequency of the blue allele? 0.43
What is the frequency of heterozygotes? 0.49
What is the frequency of birds homozygous for the blue allele? 0.19
4. If 98 out of 200 individuals in a population express the recessive phenotype, what percent of the
population are heterozygotes? 42%
