4.3 Hardy-Weinberg U4 Flashcards
What is a gene pool?
All of the alleles of all genes in a specific population
When we study specific gene pools, we often study the frequencies of different alleles
What is an allele frequency?
The number of times an allele occurs in a gene pool
What is the modified definition of evolution?
Evolution is often described as a change in allele frequency over time
What does the hardy weinberg principle state?
Allele frequencies in a population should not change unless being acted upon by an evolutionary force.
What are the 5 evolutionary forces?
Finite population size (genetic drift)
Nonrandom Mating
Mutation
Gene Flow
Natural Selection
What is Genetic Drift?
Random change in allele frequency
What is nonrandom mating?
Individuals choose mates based on specific features
What is mutation?
Causes the introduction of new alleles into the population
What is gene flow?
Genes move as individuals immigrate or emigrate
What is natural selection?
Some traits confer a selective advantage allowing an organism to be more likely to survive and reproduce; this eventually can produce adaptations!
If evolution is occuring, what is true about the evolutionary forces?
- Genetic drift is taking place; population may be small
- Mating is nonrandom and may include sexual selection
- Mutations are occuring
- Individuals are immigrating or emigrating
- Natural selection is producing adaptations
If evolution is NOT occuring, what is true about the evolutionary forces?
- genetic drift is not taking place; the population is large
- Mating is randim; individuals are not choosing mates for specific traits
- Mutations are not occurring
- Individuals are not migrating
5.Organisms with specific traits are not surviving and reproducing at a higher rate;
What is a genetic Bottleneck?
A change in allele frequency due to a reduction in population size, often following a catastrophic event or environmental change
What is the founder effect?
A change in allele frequency due to the creation of a new population by a few individuals that are not genetically representative of the original population
When is a population in equilibrium?
If NONE of the five evolutionary forces are acting on a population, it is said to be in equilibrium!
