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Genitcal Theory of Natural Selection
Genitcal Theory of Natural Selection

... Allele Frequency - the proportion of gene copies in a population that are at a given allele Evolution - origin of genetic variation by mutation or recombination, followed by changes in the frequencies of alleles and genotypes Fitness - the success of an entity in reproducing; average contribution of ...
Chapter 15 and 16 Quiz
Chapter 15 and 16 Quiz

... ____ 23. The number of phenotypes produced for a given trait depends upon a. the number of genes that control the trait. b. which form of the trait is dominant. c. the relative frequencies of the various alleles. d. the relationship of allele frequencies to Mendelian ratios. ____ 24. A polygenic tra ...
Lecture 24 Evolution Genotype vs. Phenotype Ontogeny Genotype
Lecture 24 Evolution Genotype vs. Phenotype Ontogeny Genotype

... individual organism to optimize the energy flow to maintain its nonequilibrium state long enough to reproduce (survival fitness) • 2nd approximation: reproductive fitness = the relative efficiency at producing viable ...
Topic 10 Genetics and Evolution
Topic 10 Genetics and Evolution

... • Large gene pools create large variation • Small gene pools create small variation • Allele frequency measures the proportion of a specific allele in a population. • Does not mean what % of the population have the allele. ...
Example - Harrison High School
Example - Harrison High School

File
File

...  Darwin devoted much of On The Origin of Species to exploring ...
Chapter 4 Heredity and Evolution
Chapter 4 Heredity and Evolution

... Genetic drift is directly related to population size. Genetic drift occurs when some individuals contribute a disproportionate share of genes to succeeding generations. Drift may also occur solely because the population is small: Alleles with low frequencies may simply not be passed on to offspring ...
LEQ: What did Mendel discover about the patterns of inheritance?
LEQ: What did Mendel discover about the patterns of inheritance?

... Monohybrid Crosses  Genetic cross of individuals differing in one trait  Trait – a characteristic that is inherited from parent to offspring; controlled by a gene  Examples: flower color, plant height, etc… ...
LEQ: What did Mendel discover about the patterns of inheritance?
LEQ: What did Mendel discover about the patterns of inheritance?

... Monohybrid Crosses  Genetic cross of individuals differing in one trait  Trait – a characteristic that is inherited from parent to offspring; controlled by a gene  Examples: flower color, plant height, etc… ...
Population genetics theory (lectures 7
Population genetics theory (lectures 7

... to each other, at a rate that is controlled by the migration rates. In the end their gene frequencies will be expected to be the same as if all the gene copies at that locus had been dumped into one big gene pool. 8. Natural selection and genetic drift can cause gene frequencies in different populat ...
Sex-Linked Genes
Sex-Linked Genes

... * Red-Green color blindness is an example of a sex-linked trait. ...
Questions - Kettering Science Academy
Questions - Kettering Science Academy

... (a) Scientists investigated one aspect of diet on the growth of six people. When the six people were babies, they had different masses of calcium in their diets. The height of each person was recorded when they were 10 and 18 years old. The results are shown in the table. ...
SBI 3U1 – EVOLUTION UNIT TEST REVIEW
SBI 3U1 – EVOLUTION UNIT TEST REVIEW

... on evolution: Buffon, Lamarck, Lyell, Malthus, Wallace, Darwin. 2. How do Lamarck’s explanations of adaptation differ from those of Darwin? 3. Define genetic bottlenecks and the founder effect. Give an example of each. 4. State the conditions required for Hardy-Weinberg equilibrium. State the equati ...


... 3. In a certain population, approximately one child in 2500 is homozygous for the gene z. Assuming Hardy-Weinberg equilibrium, what is the proportion of “carriers” (heterozygotes) in the population? 4. The frequency of sickle-cell anemia (ss) among the children in one malarial region of Africa is 14 ...
0 Mutation Selection Balance (very brief notes)
0 Mutation Selection Balance (very brief notes)

... 0.4 Heterozygote advantage If mutation cannot explain the high frequency of the CF allele, then what other explanations are possible? One possibility is that there is that the mutation may have a fitness advantage in heterozygotes. When the heterozygote has the highest fitness then neither allele wi ...
Gene pool
Gene pool

... • Random mating? An organism’s genotype does influence its mate selection, the physical efficiency and frequency of mating, its fertility so random mating just doesn’t exist! • No natural selection. All alleles have equal chance of existing. ...
Unit 4.1 Evolution Review Game File
Unit 4.1 Evolution Review Game File

Population Genetics - Nicholls State University
Population Genetics - Nicholls State University

Population Genetics - Nicholls State University
Population Genetics - Nicholls State University

... factors may result in some genotypes not mating in the proportions expected. As a result, some genotypes may increase in frequency quickly while other decrease in frequency. Even if a population is large, if few individuals produce the next generation, the alleles those individuals have will be more ...
Evolution Unit 5 Overview
Evolution Unit 5 Overview

... resistance, while naturally resistant varieties survived and reproduced. 25. Although similar in many respects, two species of organisms exhibit differences that make each well adapted to the environment in which it lives. The process of change that may account for these differences is evolution. ...
The Genetic Engine
The Genetic Engine

... • Natural selection can “happen” if the trait undergoing selective pressure is genetically determined • Natural selection can only work toward traits' that increase fitness for survival and reproduction • Natural selection acts by changing the frequency of alleles in the gene pool over time – thus p ...
HARDY-WEINBERG Practice - local.brookings.k12.sd.us
HARDY-WEINBERG Practice - local.brookings.k12.sd.us

... cause allele frequencies to not change? non-evolving population REMOVE all agents of evolutionary change 1. very large population size (no genetic drift) 2. no migration (no gene flow in or out) 3. no mutation (no genetic change) 4. random mating (no sexual selection) 5. no natural selection (everyo ...
Simulating Population Genetics
Simulating Population Genetics

... lethal recessive; that is, if the a allele is lethal recessive, aa mice die at birth but Aa and AA mice don’t. How does this change the equilibrium? Can any starting conditions change the final equilibrium? In some inherited lethal recessive diseases, such as Huntington’s chorea, alleles continue to ...
Recessive and dominant heredity in humans
Recessive and dominant heredity in humans

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Genetic drift



Genetic drift (or allelic drift) is the change in the frequency of a gene variant (allele) in a population due to random sampling of organisms.The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces. A population's allele frequency is the fraction of the copies of one gene that share a particular form. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation.When there are few copies of an allele, the effect of genetic drift is larger, and when there are many copies the effect is smaller. In the early twentieth century vigorous debates occurred over the relative importance of natural selection versus neutral processes, including genetic drift. Ronald Fisher, who explained natural selection using Mendelian genetics, held the view that genetic drift plays at the most a minor role in evolution, and this remained the dominant view for several decades. In 1968, Motoo Kimura rekindled the debate with his neutral theory of molecular evolution, which claims that most instances where a genetic change spreads across a population (although not necessarily changes in phenotypes) are caused by genetic drift. There is currently a scientific debate about how much of evolution has been caused by natural selection, and how much by genetic drift.
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