Term
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Definition
| A group of individuals of the same species that occupy the same environment. |
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Term
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Definition
| All of the alleles for every gene in a given population. |
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Term
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Definition
| the frequency that a specific allele will reproduce in a non evolving population |
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Term
| Define: genotype frequency |
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Definition
| the frequency that a specific genotype will reproduce in a non evolving population |
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Term
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Definition
| Changes in a population’s gene pool from generation to generation. |
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Term
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Definition
| Relative likelihood that a genotype will contribute to the gene pool of the next generation as compared with other genotypes. |
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Term
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Definition
| Changes in populations of living organisms that promote their survival and reproduction in a particular environment. |
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Term
| Explain how new alleles are produced. |
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Definition
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Term
| State the Hardy-Weinberg law and list the five assumptions for the maintenance of genetic equilibrium. |
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Definition
It predicts an equilibrium if:
-No new mutations occur
-No natural selection occurs
-The population is so large that allele frequencies do not change due to random chance.
-No migration occurs between different populations.
-Random mating occurs |
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Term
| Discuss how genetic drift (bottleneck and founder effect) alter allele frequencies or genotypic frequencies in a population. |
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Definition
bottleneck- A population can be reduced
dramatically by a natural disaster.
Now only a few individuals
contribute to the gene pool.New population likely to have less
genetic variation.
founder- Small group of individuals separates from a larger population and
establishes a colony in a new location. Relatively small founding population expected to have less genetic
variation than original population.
Allele frequencies in founding population may differ markedly from
original population. |
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Term
| Discuss how gene flow alter allele frequencies or genotypic frequencies in a population. |
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Definition
Gene flow is the movement of alleles between populations by migration.
Migration tends to reduce differences in allele frequencies between the 2
populations. Tends to increase genetic diversity within a population. |
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Term
| Discuss how nonrandom mating (forms of nonrandom mating) alter allele frequencies or genotypic frequencies in a population. |
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Definition
Assortative- Positive assortative mating:Individuals with similar phenotypes are more likely to mate -Increases the proportion of homozygotes and decreases
heterozygotes.
Negative assortative mating: Dissimilar phenotypes mate preferentially
-Increases numbers of heterozygotes
Inbreeding- mating of two genetically related individuals
-May have negative consequences
with regard to recessive alleles.In humans, increases the frequency of
recessive abnormalities |
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Term
| Discuss how mutation alter allele frequencies or genotypic frequencies in a population. |
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Definition
| it can introduce new alleles into the gene pool |
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Term
| Discuss how natural selection alter allele frequencies or genotypic frequencies in a population. |
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Definition
| the individuals who adapt due to natural selection have a better chance of survival |
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Term
| Discuss directional selection and its' effect on variation and the type of environment in which each occurs. |
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Definition
| Individuals at one extreme of a phenotypic range have greater reproductive success in a particular environment.Favors an extreme phenotype and changes the characteristics of a population. |
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Term
| Discuss disruptive selection and its' effect on variation and the type of environment in which each occurs. |
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Definition
| Favors the survival of two or more different genotypes that produce different phenotypes. The fitness values of a particular genotype are higher in one environment and lower in a different environment. The fitness values of the other genotype vary in the opposite manner. |
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Term
| Discuss balancing selection and its' effect on variation and the type of environment in which each occurs. |
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Definition
Maintains genetic diversity in a population.
malaria/sickle cell |
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Term
| Discuss stabilizing selection and its' effect on variation and the type of environment in which each occurs. |
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Definition
Favors the survival of individuals
with intermediate phenotypes and
selects against extreme phenotypes. Preserves the characteristics of a population. Occurs in a relatively stable environment. |
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Term
| Discuss sexual selection and its' effect on variation and the type of environment in which each occurs. |
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Definition
Form of natural selection that is directed at certain traits of
sexually reproducing species that make it more likely for individuals to find or choose a mate and/or engage in successful mating. |
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