Hardy Weinberg
1. If the frequency of allele p in a certain population is 0.78, what is the frequency of allele q? (1)
2. If the frequency of recessive homozygotes for a particular gene within a population is 0.36, what is the frequency of the recessive allele? (1)
3. What does the “2pq” part of the equation represent? (1)
The peppered moth Biston betularia showed an increase in melanic (dark) forms during the industrial revolution. In most polluted areas of the UK the melanic form became the most common. Moth colour is determined by one single locus, and the melanic form is the dominant allele, with the paler form being the recessive allele.
In one study of a heavily polluted area near Birmingham, Kettlewell (1956) observed a frequency of 87% melanic peppered moths.
4. What is the frequency of recessive homozygotes? (1) a) 0.87 b) 0.76 c) 0.93 d) 0.13 e) 0.36
5. What is the frequency q of the recessive allele? (1) a) 0.87 b) 0.76 c) 0.93 d) 0.13 e) 0.36
6. What is the frequency of heterozygotes? (1) a) 0.36 b) 0.46 c) 0.56 d) 0.66 e) 0.76
7. List three assumptions of the Hardy Weinberg model (3)
8. In a given population, only the "A" and "B" alleles are present in the ABO system; there are no individuals with type "O" blood or with O alleles in this particular population. If 150 people have type A blood, 100 have type AB blood, and 50 have type B blood, what is the frequency of allele B in this population? (2) a) 0.25 b) 0.33 c) 0.5 d) 0.66 e) 0.75
At the PGI locus in the Ojibway pond population of Daphnia, Spitze et al. found two alleles, S and S-, and the number of individuals with each genotype was 42 SS, 48 SS-, and 38 S-S-.
9. What is the frequency of allele S? (2) a) 0.48 b) 0.50 c) 0.52 d) 0.54 e) 0.56
10. Using the S and S- allele frequencies, what would the expected frequency of heterozygotes (SS-)