Question

-Does the frequency of an allele in a population have anything to do with whether or not an allele is dominant or recessive? Why?

-What process does play a role in determining the frequency of a given allele in a population?

-Choose either the earlobe shape gene or the widow's peak gene. Assuming that natural selection is the primary force contributing to the frequency of the two alleles of that gene, provide a hypothesis as to why the particular allele of that gene that you found to be more frequent might be more common than the other.

Answer 1

1. No
The frequency of an allele in a given population does not depend upon whether it is dominant or recessive.
The frequency of an allele in a given population depends upon its fitness level and the advantage that it provides against selection pressure.

2. Natural selection exerts pressure on alleles and determines the relative frequencies of alleles in a population.
Natural selection is the driving force of evolution. Alleles that provide a selective advantage to the prevailing environmental conditions are selected and non-adaptive/deleterious alleles are subsequently eliminated from the population.

3. Earlobe pattern in humans does not follow simple Mendelian inheritance as it is a quantitative trait.
Widow's peak is considered a dominant trait in humans. There is no proven selective advantage to it. However, it is considered a mark of beauty and manhood.