Bio 123: PP4 Material Flashcards
Define microevolution
The change in allele frequencies in a population throughout time.
Explain the Hardy-Weinberg Equilibrium Model
It is used as a baseline to compare an evolving population to one that remains constant without evolutionary forces acting upon it. There are positive controls and negative controls. There is a part missing, ask classmate for his notes that he wrote
What are the four processes that drive populations out of genetic equilibrium?
1) Mutations
2) Genetic Drift
3) Gene Flow
4) Selection
What are mutations?
Raw material for evolutionary change. They are changes in alleles. They also occur at relatively low rates and can appear more often due to exposure to hazardous material such at radioactive material.
What are the conditions under the Hardy-Weinberg equilibrium?
Evolution is not occurring if:
1) No mutations occur
2) There is no genetic flow (meaning that the population is fully isolated)
3) The alleles present have no effect on the survival or reproduction ability of that population
4) Random mating (there is no active mate choice)
What is the purpose of having a genetic equilibrium model (the Hardy-Weinberg Model)?
It serves to positively identify the mechanisms that drive changes in allele frequency.
Polygenic
Multiple alleles that control a trait
Incomplete Dominance
Bb
Complete Dominance
ignore
Deleterious mutation
Mutations that have a negative affect and decreases an organisms fitness.
Lethal Mutations
Mutations that lead to the death of an organism. The organism is not even born.
Neutral Mutations
Mutations that have 0 affect on an organisms fitness.
Beneficial Mutations
Mutations that have a positive affect on an organisms fitness and is therefore favored by natural selection.
Genetic Drift
In small populations, some alleles can randomly become fixed (one allele can be at 100% and the other ends up at 0%) which causes a loss of some alleles and an overall loss of genetic diversity.
It usually results in a decline of an organism fitness.
What is Homozygous Dominant?
AA