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| 6180273831 | microevolution | evolution on its smallest scale | 0 | |
| 6180273832 | genetic variation | differences among individuals in the composition of their genes or other DNA sequences | 1 | |
| 6180273833 | 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 | |
| 6180273834 | formation of genetic variation | formation of new alleles, altering gene number of position, rapid reproduction, sexual reproduction | 3 | |
| 6180273835 | population | a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring | 4 | |
| 6180273836 | gene pool | all copies of every type of allele at every locus in all members of the population | 5 | |
| 6180273837 | Hardy-Weinberg equilibrium | a population that isn't evolving | 6 | |
| 6180273838 | conditions for Hardy-Weinberg equilibrium | No mutations, random mating, no natural selection, extremely large population size, no gene flow | 7 | |
| 6180273839 | adaptive evolution | evolution that results in a better match between organisms and their environment (caused by natural selection) | 8 | |
| 6180273840 | genetic drift | allele frequencies fluctuating unpredictable from one generation to the next, especially in small populations | 9 | |
| 6180273841 | 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 | |
| 6180273842 | bottleneck effect | a severe drop in population which results in an overrepresented allele an underrepresented allele | 11 | |
| 6180273843 | 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 | |
| 6180273844 | Gene flow | the transfer of alleles into or out of a population due to the movement of retile individuals or their gametes | 13 | |
| 6180273845 | relative fitness | the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals | 14 | |
| 6180273846 | 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 |
| 6180273847 | Disruptive selection | occurs when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes |  | 16 |
| 6180273848 | Stabilizing selection | acts against extreme phenotypes and favors intermediate variants |  | 17 |
| 6180273849 | sexual selection | a form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates | 18 | |
| 6180273850 | sexual dimorphism | a diference in secondary sexual characteristics between males and females of the same species. a result of sexual selection | 19 | |
| 6180273851 | intrasexual selection | selection within the same sex. individuals of one sex compete directly for mates of the opposite sex. most common among males | 20 | |
| 6180273852 | 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 | |
| 6180273853 | balancing selection | natural selection that maintains two or more phenotypic forms in a population | 22 | |
| 6180273854 | 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 | |
| 6180273855 | frequency-dependent selection | the fitness of a phenotype depends on how common it is in the population | 24 | |
| 6180273856 | 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 | |
| 6180273857 | 5 conditions of HW | 1) Populations must be large (can happen) 2) Populations must be isolated (no genetic drift...hard to happen) 3) No mutations occur (impossible) 4) Mating is completely random (can never be met) 5) Every species has equal chance of survival (impossible due to natural selection) | 26 | |
| 6180273858 | What two processes make evolution possible? | Mutation and sexual reproduction | 27 | |
| 6180273859 | Why is Diploid useful? | Allows for recessive genes to be hidden | 28 | |
| 6180273860 | Point Mutation | -Mutation affecting one gene -Could be harmless (synonmous) -Could cause a new protein that is harmful (most common), a new protein that is better, or a protein that functions like the original | 29 | |
| 6180273861 | Natural selection act on... | Individual, but populations evolve | 30 | |
| 6180273862 | Forms of variation | Sexual recombination and mutation | 31 | |
| 6180273863 | Sexual combination | The re-arranging of genes during meoisis which natural selection acts upon (new phenotypes, same genotypes) | 32 | |
| 6180273864 | Mutation | new genotypes | 33 | |
| 6180273865 | Limits to natural selection | -can only act on exisitng variations -Historical limits (ex; ice age) | 34 | |
| 6180273866 | Gene Duplication | gene goes from one chromsome to the other, results in new protein (ex: myoglobin and hemoglobin) | 35 | |
| 6180273867 | neutral mutation | -naturally evolving species due to biological clock -examples are how we evolved from slugs, and you can compare our similarities by cytocrhom c and hemoglobin | 36 | |
| 6180273868 | Evolution | descent with modification; change over time; both pattern and process | 37 | |
| 6180273869 | Fossils | 1) groundwork for Darwin's ideas 2) remains or traces of organisms from the past 3) usually found in sedimentary rock= appears in layers (strata) | 38 | |
| 6180273870 | Natural Selection | cause of adaptive evolution | 39 | |
| 6180273871 | Artificial Selection | 1) Humans have modified other species by selecting and breeding animals with desired traits 2) Darwin experimented with pigeon breeding to test natural selection | 40 | |
| 6180273872 | Homology | similarity resulting from common ancestry | 41 | |
| 6180273873 | Homologous structures | anatomical structures that function on a basic plan due to common ancestry; have differentiated to fit different function; verbrate | 42 | |
| 6180273874 | Vestigial Structure | 1) remnants of features that served important homologies in organism's ancestors 2) have lost or reduced function | 43 | |
| 6180273875 | Phylogenetic trees (AKA evolutionary trees) | 1) show hypothesis of evolutionary relationships bet. different organismal groups 2) use many different types of data: anatomical differences & DNA sequence data | 44 | |
| 6180273876 | Convergent Evolution | 1) evolution of similar (analogous) features in distantly related groups 2) happen when groups independently adapt to similar environments in similar ways 3) does not provide ancestry | 45 | |
| 6180273877 | Biogeography | geographic distribution of species (living and extinct) | 46 | |
| 6180273878 | Pangea | single large continent formerly existing on Earth; separated by continental drift | 47 | |
| 6180273879 | endemic | (of a plant or animal) native or restricted to a certain country or area. | 48 | |
| 6180273880 | catatrophism | the theory that changes in the earth's crust during geological history have resulted chiefly from sudden violent and unusual events. | 49 | |
| 6180273881 | uniformitarianism | the theory that changes in the earth's crust during geological history have resulted from the action of continuous and uniform processes. | 50 | |
| 6180273882 | Pangea | was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It assembled from earlier continental units approximately 300 million years ago, and it began to break apart about 175 million years ago. | 51 |
