6385704531 | Macroevolution | Evolutionary change above species level. | 0 | |
6385704532 | Microevolution. | Evolutionary change within allele frequencies in species. | 1 | |
6385704533 | Hardy-Weinberg Equations | Used to calculate allele frequencies to determine if evolution is occuring. | 2 | |
6385704534 | Allele Frequency Equation | p + q = 1 | 3 | |
6385704535 | p | Frequency of dominant allele. | 4 | |
6385704536 | q | Frequency of recessive allele. | 5 | |
6385704537 | Genotype Frequency Equation | p^2 + 2pq + q^2 = 1 | 6 | |
6385704538 | p^2 | Frequency of homozygous dominant individuals. | 7 | |
6385704539 | 2pq | Frequency of heterozygote individuals. | 8 | |
6385704540 | q^2 | Frequency of homozygous recessive individuals. | 9 | |
6385704541 | Hardy-Weinberg Equilibrium | Large population size, no gene flow (immigration/ emigration), no mutations, random mating, and no natural selection. | 10 | |
6385704542 | Factors that Lead to a Change in Allele Frequency | Small population size (genetic drift), bottleneck, founder effect. | 11 | |
6385704543 | Genetic Drift | A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next; effects are most pronounced in small populations. | 12 | |
6385704544 | Bottleneck | Genetic drift that occurs when the size of a population is reduced, as by a natural disaster or human actions; typically, the surviving population is no longer genetically representative of the original population | 13 | |
6385704545 | Founder Effect | Genetic drift that occurs when a few individuals become isolated from a larger population whose gene pool composition is not reflective of that of the original population. | 14 | |
6385704546 | Sexual Selection | Adaptive changes that lead to an increased ability to secure a mate. | 15 | |
6385704547 | Sexual Dimorphism | A difference in secondary sexual characteristics between males and females of the same species (size, color, ornamentation, behavior). | 16 | |
6385704548 | Natural Selection | Only mechanism of evolution that leads to adaptation to environment. | 17 | |
6385704549 | Directional Selection | A mode of natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype. | ![]() | 18 |
6385704550 | Disruptive Selection | Describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups. | ![]() | 19 |
6385704551 | Stabilizing Selection | Instead of favoring individuals with extreme phenotypes, it favors the intermediate variants. It reduces phenotypic variation and maintains the status quo. | ![]() | 20 |
6385704552 | Diploidy | Unfavorable recessive alleles can "hide" in the population as heterozygotes. Only expressed when two heterozygotes have offspring. | 21 | |
6385704553 | Balanced Polymorphism | Natural selection maintains stable frequencies of two or more phenotypes in a population (heterozygote advantage). | 22 | |
6385704554 | Genetic Variation | Differences among individuals in the composition of their genes or other DNA sequences. | 23 | |
6385704555 | Gene Flow | The transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes. | 24 | |
6385704556 | Neutral Variation | Differences in DNA sequence that do not confer a selective advantage or disadvantage. | 25 |
AP Biology Chapter 21 Flashcards
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