1. The frequency of two alleles in a gene pool is 0.1 (A) and
0.9 (a). What is the percentage of heterozygous individuals?
Of homozygous recessives?
Assume the population is in H-W equilibrium.
2. Allele B for white wool is dominant over allele b, for black wool. In a sample of 900 sheep, 891 are white and 9 are black.
Estimate the allelic frequencies in this sample, assuming the
population is in equilibrium
3. In a population that is in H-W equilibrium, the frequency of recessive homozygotes of a certain trait is 0.09. What is the percentage of individuals homozygous for the dominant trait?
4.In a population that is in H-W equilibrium, 36 percent of individuals are recessive homozygous for a certain trait.
For the same trait, what is the percentage in this population
of homozygous dominant individuals? Of heterozygous individuals?
5. Allele T, for the ability to taste a particular chemical, is dominant over allele t, for the inability to taste it. At Cornell University, out of 400 students surveyed, 64 were found to be non-tasters. What is the percentage of heterozygous tasters? Assume the population is in equilibrium.
6. In humans, Rh -positive individuals have Rh marker on their red blood cells, while Rh-negative individuals do not. Assume that the Rh-positive phenotype is produced by the dominant allele, Rh, and the Rh-negative phenotype is produced by the recessive allele, rh. In a population that is in H-W equilibrium, if 84 percent of the individuals are Rh-positive, what are the frequencies of the Rh and rh allele at this locus?
7. In corn, yellow kernel colour is governed by a dominant allele; white, by its
recessive allele. A random sample of 1000 kernels from a population that is in equilibrium reveals that 910 are yellow and 90 are white. What are the frequencies of the yellow and white alleles in this population? What is the percentage of heterozygotes?
8. A rare disease due to a recessive allele which is lethal when homozygous occurs with a frequency of one in a million. How many individuals in a town of 14 000 are expected to carry this allele?
THE ANSWERS!!