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| 5114480728 | microevolution | evolution on its smallest scale | 0 | |
| 5114480729 | genetic variation | differences among individuals in the composition of their genes or other DNA sequences | 1 | |
| 5114480730 | neutral variation | differences in DNA sequences that do not confer s selective advantage or disadvantage, usually a result of point mutations in noncoding regions | 2 | |
| 5114480731 | formation of genetic variation | formation of new alleles, altering gene number of position, rapid reproduction, sexual reproduction | 3 | |
| 5114480732 | population | a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring | 4 | |
| 5114480733 | gene pool | all copies of every type of allele at every locus in all members of the population | 5 | |
| 5114480734 | Hardy-Weinberg equilibrium | a population that isn't evolving | 6 | |
| 5114480735 | conditions for Hardy-Weinberg equilibrium | No mutations, random mating, no natural selection, extremely large population size, no gene flow | 7 | |
| 5114480736 | adaptive evolution | evolution that results in a better match between organisms and their environment (caused by natural selection) | 8 | |
| 5114480737 | genetic drift | allele frequencies fluctuating unpredictable from one generation to the next, especially in small populations | 9 | |
| 5114480738 | founder effect | when individuals separate from the population, the smaller group may establish a new population whose gene pool differs from the source population. The larger population (the source) will not be effected by genetic variation | 10 | |
| 5114480739 | bottleneck effect | a severe drop in population which results in an overrepresented allele an underrepresented allele | 11 | |
| 5114480740 | Effects of genetic variation | genetic drift is significant in small populations, genetic drift can cause allele frequencies to change at random, genetic drift can lead to a loss of genetic variation within populations, genetic drift can cause harmful alleles to become fixed | 12 | |
| 5114480741 | Gene flow | the transfer of alleles into or out of a population due to the movement of retile individuals or their gametes | 13 | |
| 5114480742 | relative fitness | the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals | 14 | |
| 5114480743 | directional selection | occurs when conditions favor individuals exhibiting one extreme of a phenotype range, thereby shifting a population's frequency curve for the phenotypic character in one direction or the other. Common when a population changes or members migrate |  | 15 |
| 5114480744 | Disruptive selection | occurs when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes |  | 16 |
| 5114480745 | Stabilizing selection | acts against extreme phenotypes and favors intermediate variants |  | 17 |
| 5114480746 | sexual selection | a form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates | 18 | |
| 5114480747 | sexual dimorphism | a diference in secondary sexual characteristics between males and females of the same species. a result of sexual selection | 19 | |
| 5114480748 | intrasexual selection | selection within the same sex. individuals of one sex compete directly for mates of the opposite sex. most common among males | 20 | |
| 5114480749 | intersexual selection | also called mate choice; individuals of one sex (usually females) are choosy in selecting their mates from the other sex. It usually depends of the showiness of the male's appearance or behavior | 21 | |
| 5114480750 | balancing selection | natural selection that maintains two or more phenotypic forms in a population | 22 | |
| 5114480751 | heterozygote advantage | if individuals who are heterozygous at a particular locus have a greater fitness than do both kinds of homozygotes, they exhibit heterozygote advantage | 23 | |
| 5114480752 | frequency-dependent selection | the fitness of a phenotype depends on how common it is in the population | 24 | |
| 5114480753 | Why can't natural selection fashion perfect organisms? | 1. Selection can act only on existing variations. New advantageous alleles do not arise on demand. 2. Evolution is limited by historical constraints. New structures aren't formed, but instead evolution adapts to the existing structures. 3. Adaptations are often compromises. We can be versatile and athletic but our limbs are prone to sprains. 4. Chance, natural selection, and the environment interact. Alleles are sometimes "left behind" or the organism lives in a constantly changing environment | 25 |
