19.2 The Causes of Gene Pool Change Flashcards
What is Genetic Diversity?
The degree of genetic variation within a species or populations
What is a Mutation?
A change that occurs in the DNA of an individual
What are Back mutations?
Mutation that reverse the effects of former mutations
What is Gene Flow?
The net movement of alleles from one population to another
What is the result of Gene Flow?
It increases genetic diversity but reduces genetic differences among populations
What is non-random mating?
Mating among individuals on the basis of mate selection for a particular phenotype or due to inbreeding
What are two examples of Non-random mating?
Mating based on phenotypes and inbreeding
Why do inbred animals have a higher chance deformities and health problems?
Because there are higher chances of homozygous recessive alleles being expressed
What positive effects can inbreeding have?
If homozygous recessive individuals fail to breed, harmful recessive alleles may be eliminated from the gene pool over time
What type of population is more likely to lose alleles from its gene pool?
A small population is more likely than a large population
What is genetic drift?
A change in allele frequencies due to chance events in a small breeding population
Why does Genetic Drift not affect large populations?
Because chance events are unlikely to affect overall allele frequencies
What is the Founder Effect?
The gene pool change that occurs when a few individuals start a new isolated population
What is the Bottleneck Effect?
Gene pool change that results from a rapid decrease in population size
What is Heterozygote Advantage?
A survival benefit for those who inherit two different alleles for the same trait
