Question

In 1908 Hardy and Weinberg published papers showing that the binomial or multinomial could be applied in genetics to predict the frequencies of genotypes when allele frequencies where known. The formal algebraic proof of this Hardy-Weinberg Equilibrium Law assumes that there is no mutation in the population. This assumption is necessary, because a. organisms reproduce sexually and litter or family sizes vary. b. populations will exhibit random sampling changes in allele frequency. c. populations are not infinite and the Hardy-Weinberg proof is only a very crude approximation when natural selection is acting. d. populations are not closed and reproduce both sexually and asexually so an infinite size population is required to preserve genetic variation. e. allowing alleles to change would alter their frequencies.

Answer 1

b. populations will exhibit random sampling changes in allele frequency.

The following are the assumptions of Hardy-Weinberg equilibrium.

1). Non-random mating- A trait would be in Hardy-Weinberg equilibrium if we mate randomly; means if we do not choose partners, the traits mix randomly and follow Hardy-Weinberg equilibrium. For example, blood types are in Hardy-Weinberg equilibrium because we do not choose our partner based on blood type.

2. Individuals must not move to different geological regions (migration), means absence of gene flow.

3. The population size must be large (no genetic drift that occurs in small populations).

4. Absence of mutations. This is because the populations will exhibit random sampling changes in allele frequency, which which alters the allele frequency.

5. No natural selection in the population. Generally, individuals with same genotype tend to mate with each other to produce more viable, fertile offspring than with the individuals of other genotype (natural selection), this must be absent.

In a naturally occurring population, the assumptions are violated by means of non-random mating, migration and genetic drift.