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Unit 14
Population Genetics, Natural Selection
| Question | Answer |
|---|---|
| Evolution | changes in gene frequencies in populations overtime |
| Evolutionary Fitness | the ability of an organism or allele to survive and reproduce to other individuals or alleles within the population |
| Population | A group of organisms that interbreed such as to produce viable offspring |
| Gene Frequency | Numeric rate at which a gene occurs in a gene pool, relative to the other alleles in its gene pair |
| Genetic Diversity | The variety of genes and genotypes in a gene pool |
| Genetic Drift | Changes in gene frequencies owing to random factors |
| Gene Flow | Movement of genes into or out of a population resulting from migration |
| Mutation | Alteration to the nucleotide sequence of a gene |
| Directional Selection | genetically-related change in mean overtime follows a progressive trend. selective pressure moves population from one average to another |
| Stabilizing Selection | No genetically-related change in population mean overtime. Selective pressure keeps population centered around an average. |
| Disruptive Selection | Genetically-related change in mean overtime that produces two "means" (modes). Selective pressure splits population around two "averages" or modes. Leads to Speciation |
| How to calculate gene frequencies | Example A = 11, 11/20 = .55 percent a = 9, 9/20 = .45 percent 11+9 = 20 |