Term
| deleterious recessive allele |
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Definition
it is expected that a deleterious allele will persist in a population at very low frequencies for many loci
recessive deleterious alleles are "hidden" from natural selection by their dominant non-deleterious counterparts. An individual carrying a single recessive deleterious allele will be healthy and can easily pass the deleterious allele into the next generation.
Cannot really be removed because they are repeatidally introduced to the pluton through mutation and migration
Because it is hard to remove they go torawds stable equilibrium |
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Term
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Definition
measure of the rate at which various types of mutations occur during some unit of time
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Term
| mutations and the constraints that effect them... |
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Definition
No reason to think that there are any
constraints on mutation at the level of DNA as to what mutations can occur |
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Term
| frequency dependent selection |
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Definition
NEGATIVE DEPENDENT SELECTION: The rarer phenotype in the population has the higher fitness
POSITIVE DEPENDENT SELECTION: positive frequency-dependent selection gives an advantage to common phenotypes |
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Term
| what is the difference between effective population size and census population size? |
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Definition
census population size = N :: total number counted
effective population size= Ne:: the number of breeding individuals in an idealized population that would show the same amount of dispersion of allele frequencies under random genetic drift or the same amount of inbreeding as the population under consideration |
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Term
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Definition
Most mutations are deleterious • Selection will act to eliminate them • Deleterious alleles persist in the population because they are continuously reintroduced by mutation • When the rate of creation of new alleles by mutation is the same as the rate at which they are removed from the population the frequency of the allele is at equilibrium
Q hat! = square root of mutation rate/selection coefficient
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Term
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Definition
a genetic bottleneck
Occurs when a new population is founded by a small number of colonists
Or a larger population has crashed because of external forces
colony founded by a small number of individuals will suffer from some loss in genetic diversity
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Term
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Definition
have higher fitness due to genetic diversity
example: sickel cell anemia heterozygote people
Leads to stable equilibrium
Rare in nature |
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