6.1.6 Population Genetics

Question 1

Definition of Evolution

Answer 1

Evolution is currently defined as changes in allele proportions within a population over time.

Question 2

Gene Flow

Answer 2

The movement and exchange of genes or alleles from one population of species to another.

For example, if a population with a new allele assimilates into a larger population, the allele may be reintroduced through gene flow.

Question 3

Genetic Drift

Answer 3

The drifting of the frequency of a gene variant (allele) relative to that of the other alleles in a population over time as a result of a chance event.

Question 4

Bottleneck Effect

Genetic Drift

Answer 4

1. A chance event creating a drastic decrease in population size that alters the allele frequency and ratio in the population.
2. As the population repopulates, the new population will maintain this altered phenotypic ratio.

Question 5

Founders Effect

Genetic Drift

Answer 5

1. A new population is created from a sample of the original population that does not represent the original allele frequencies and ratios. This sample can be purposely chosen through reduced variation or be a non-random sample.
2. This reduces the alleles in the gene pool, therefore altering the allele frequencies of the new population.

Question 6

Gene Pool

Answer 6

The gene pool is the stock of different genes in an interbreeding population.