Unit #11: Population Genetics Flashcards
Where does genetic variation come from?
Meiosis (passing down of “old” alleles) and mutations
What types of mutations are there?
point, frameshift, inversions, duplications, translocation
How do new alleles form?
Mutations
Are mutations in somatic cells heritable?
No
What is an example of an induced mutation?
Ionizing radiation (radiation from the sun)
What is the definition of population genetics?
The study of changes in the abundance of alleles that influence traits in a population.
What is a fixed allele.
That for a certain trait in a population, they all have the same allele.
What are the conditions for Hardy-Weinberg Equilibrium?
- No selection
- No mutations
- Random mating
- No gene flow
- Large population
Define the founder effect.
When a subset of a population breaks off, and moves to a new area, segregating themselves from the original population, therefore only containing a subset of the original alleles.
Define the bottleneck effect.
When a natural disaster occurs and wipes out part of a population (and their alleles), leaving only a portion of the original population.
Define gene flow.
The movement of alleles from population to population (immigration and emigration)
Is gene flow more likely than mutations to alter allele frequencies directly?
Yes
Define genetic drift.
Random changes that occur in allele frequency literally just because. ex. 5/10 plants get pollinated, therefore only their alleles get passed on.
What are the three main factors to getting to adaptive evolution?
NATURAL SELECTION, gene flow, genetic drift.
What provides the most pressure for allele frequencies to change?
Natural selection.
For a trait that is being selected for, natural selection allows for….. in allele frequencies over time
Increase
