Equilibrium principle Hardy-Weinberg | lists from white box
Gregor Mendel discovered the laws of heredity After observing several features of information has not yet been crossbreeding them, and follow Htbtautn biggest countries in the world offspring. Since Mendel's laws regarding the crossing of hereditary characteristics from generation to generation, that is, in families, biggest countries in the world the genetic makeup if you know the parents, it will be possible biggest countries in the world to know also what is the genetic makeup of their children. These laws were forgotten after publication and only re-discovered in 1900 in the meantime accepted theory of Charles Dro'in and Alfred Russel Wallace that the evolution of the species occurs through a process of natural selection, and then scientists sought biggest countries in the world to unify the theory of evolution with the theory of heredity, and apply the rules Mendel all species populations.
Genetics researchers did not know at first that there is a difference between the family and the population, in terms of the distribution of phenotypes. They believed that if a family where both parents, showing the dominant phenotype biggest countries in the world are heterozygous (Aa), the distribution of phenotypes should be among the offspring biggest countries in the world 3: 1 in favor of the dominant phenotype, and in any case should be the distribution of phenotypes in the population as well. Therefore expected to see that for each inherited trait, 75 percent of individuals (AA + Aa) shall be the dominant phenotype, and 25 percent carry the recessive phenotype (aa).
British mathematician Godfrey Hardy (Godfrey Hardy) and German physician Wilhelm Weinberg (Wilhelm Weinberg) who did not know each other, argued in 1908 that there is no connection between the distribution of phenotypes in the family and the distribution of phenotypes in the population. While the distribution of phenotypes in the family fits the expectations biggest countries in the world under the laws of Mendel, the distribution of phenotypes in the population depends only on the same population alleles frequencies. That is to say, the prospect biggest countries in the world allele from the father, whether allele A or allele a, will meet with the allele from the mother, whether allele A or allele a, is determined solely by the relative Scihoiotihm Halliim of these two genes in the population. The principle also independently discovered by Russian geneticist Tz'tbricob Sergei (Sergei Chetverikov).
What was the explanation of the three? biggest countries in the world Population of each species breeding diploid fertilization strange way, made up of individuals bearing genes Alliim, for example, allele A and allele a, and therefore each individual in the population belongs to one of three genotypes: AA, Aa, aa. The relative frequency of allele A in a given population, their frequency depends on the relative information with genotypes biggest countries in the world AA plus half drastically underestimate the relative information with genotype Aa. This incidence of allele A can be marked with the letter p. Similarly, the relative frequency of allele a given population, their frequency depends biggest countries in the world on the relative information with aa genotype relative drastically underestimate plus half of the individuals biggest countries in the world with the genotype biggest countries in the world Aa. This is the allele frequency of a signal can be marked q.
A
Can be seen from the table that the relative biggest countries in the world frequency of genotype AA is p 2, the relative frequency of genotype Aa is 2pq, and the relative frequency of genotype aa is q 2. Since the sum of the three relative abundances of all individuals is one, it is evident that the sum of p + q is also a first, as p 2 + 2pq + q 2 = 1. From this it follows that although there has been no change to frequency alleles represented biggest countries in the world by p and q, since p 2 plus pq is equal to p, and q 2 is equal to pq plus q. Result that the values p 2, q 2, 2pq, indicate the relative Scihoiotihm of genotypes AA, aa, Aa, the next generation and in fact, in all the generations that will follow.
1 couplings between the different genotypes are done completely randomly. That is, all males in the population has an equal probability of mating with a female population and vice versa. 2 any of the genotypes no advantage in terms of natural selection, and they all equally contribute gametes to the next generation. We can assume that selection is acting on the population, or it works equally to all phenotypes. 3 of the population is not mixed with other populations. It can be assumed that the population is closed to migration from within biggest countries in the world and to, or no difference in migration of individuals from the population not out and from the outside into the population. In other words, there is no possibility that the A allele carriers Details will leave the population or be added to it from the outside, more than the number of individuals carrying the allele a. 4 a very large population, and therefore the occurrence biggest countries in the world of random fluctuations in the different alleles frequencies are negligible 5 no effect of random genetic drift. Ie, there is no random variation of gene frequencies from one generation biggest countries in the world to the various Halliim - a phenomenon that is more common as a smaller population. 6 No mutation pressure. In other words, there is no unfolding of a single gene allelic form different alleles form, for example from A to a. 7 There is no bias Beauty. All heterozygosity produces the same amount of gametes A and a. 8 males alleles frequencies equal proliferation in females. 9 The origin of a population sample. 10 it is possible to distinguish between individuals in the population genetically. 11 There is no overlap between generations. In other words, there is no intergenerational pairings, for example, between parents and their offspring.
It is clear that these conditions can not fully exist in any natural population. Nevertheless, the principle of Hardy-Weinberg great importance, since it describes the theoretical distribution of the frequencies biggest countries in the world of genotypes in the population, which can serve as a basis comparable to contrast the actual observations. If researchers could not make such a comparison, then the observations were meaningless.
The principle of Hardy-Weinberg is also valuable in that it teaches us that Mendelian heredity itself, there is no inherent mechanism that may lead to changes in gene frequency in populations. Such changes, when they occur, should be hanged activity of other factors such as genetic variation, natural selection, genetic drift and migration; In fact, all the factors that drive the evolution.
Born naturalist, ancient literature lover and collector of historical information. Made through the RSS RSS Subscription - records ben.hateva@gmail.com contact page on the website image Author Recent Entries How evolved the Swiss solo thing that gets the whole world? Twilight Zone categories have interesting things in the fleet service department
Gregor Mendel discovered the laws of heredity After observing several features of information has not yet been crossbreeding them, and follow Htbtautn biggest countries in the world offspring. Since Mendel's laws regarding the crossing of hereditary characteristics from generation to generation, that is, in families, biggest countries in the world the genetic makeup if you know the parents, it will be possible biggest countries in the world to know also what is the genetic makeup of their children. These laws were forgotten after publication and only re-discovered in 1900 in the meantime accepted theory of Charles Dro'in and Alfred Russel Wallace that the evolution of the species occurs through a process of natural selection, and then scientists sought biggest countries in the world to unify the theory of evolution with the theory of heredity, and apply the rules Mendel all species populations.
Genetics researchers did not know at first that there is a difference between the family and the population, in terms of the distribution of phenotypes. They believed that if a family where both parents, showing the dominant phenotype biggest countries in the world are heterozygous (Aa), the distribution of phenotypes should be among the offspring biggest countries in the world 3: 1 in favor of the dominant phenotype, and in any case should be the distribution of phenotypes in the population as well. Therefore expected to see that for each inherited trait, 75 percent of individuals (AA + Aa) shall be the dominant phenotype, and 25 percent carry the recessive phenotype (aa).
British mathematician Godfrey Hardy (Godfrey Hardy) and German physician Wilhelm Weinberg (Wilhelm Weinberg) who did not know each other, argued in 1908 that there is no connection between the distribution of phenotypes in the family and the distribution of phenotypes in the population. While the distribution of phenotypes in the family fits the expectations biggest countries in the world under the laws of Mendel, the distribution of phenotypes in the population depends only on the same population alleles frequencies. That is to say, the prospect biggest countries in the world allele from the father, whether allele A or allele a, will meet with the allele from the mother, whether allele A or allele a, is determined solely by the relative Scihoiotihm Halliim of these two genes in the population. The principle also independently discovered by Russian geneticist Tz'tbricob Sergei (Sergei Chetverikov).
What was the explanation of the three? biggest countries in the world Population of each species breeding diploid fertilization strange way, made up of individuals bearing genes Alliim, for example, allele A and allele a, and therefore each individual in the population belongs to one of three genotypes: AA, Aa, aa. The relative frequency of allele A in a given population, their frequency depends on the relative information with genotypes biggest countries in the world AA plus half drastically underestimate the relative information with genotype Aa. This incidence of allele A can be marked with the letter p. Similarly, the relative frequency of allele a given population, their frequency depends biggest countries in the world on the relative information with aa genotype relative drastically underestimate plus half of the individuals biggest countries in the world with the genotype biggest countries in the world Aa. This is the allele frequency of a signal can be marked q.
A
Can be seen from the table that the relative biggest countries in the world frequency of genotype AA is p 2, the relative frequency of genotype Aa is 2pq, and the relative frequency of genotype aa is q 2. Since the sum of the three relative abundances of all individuals is one, it is evident that the sum of p + q is also a first, as p 2 + 2pq + q 2 = 1. From this it follows that although there has been no change to frequency alleles represented biggest countries in the world by p and q, since p 2 plus pq is equal to p, and q 2 is equal to pq plus q. Result that the values p 2, q 2, 2pq, indicate the relative Scihoiotihm of genotypes AA, aa, Aa, the next generation and in fact, in all the generations that will follow.
1 couplings between the different genotypes are done completely randomly. That is, all males in the population has an equal probability of mating with a female population and vice versa. 2 any of the genotypes no advantage in terms of natural selection, and they all equally contribute gametes to the next generation. We can assume that selection is acting on the population, or it works equally to all phenotypes. 3 of the population is not mixed with other populations. It can be assumed that the population is closed to migration from within biggest countries in the world and to, or no difference in migration of individuals from the population not out and from the outside into the population. In other words, there is no possibility that the A allele carriers Details will leave the population or be added to it from the outside, more than the number of individuals carrying the allele a. 4 a very large population, and therefore the occurrence biggest countries in the world of random fluctuations in the different alleles frequencies are negligible 5 no effect of random genetic drift. Ie, there is no random variation of gene frequencies from one generation biggest countries in the world to the various Halliim - a phenomenon that is more common as a smaller population. 6 No mutation pressure. In other words, there is no unfolding of a single gene allelic form different alleles form, for example from A to a. 7 There is no bias Beauty. All heterozygosity produces the same amount of gametes A and a. 8 males alleles frequencies equal proliferation in females. 9 The origin of a population sample. 10 it is possible to distinguish between individuals in the population genetically. 11 There is no overlap between generations. In other words, there is no intergenerational pairings, for example, between parents and their offspring.
It is clear that these conditions can not fully exist in any natural population. Nevertheless, the principle of Hardy-Weinberg great importance, since it describes the theoretical distribution of the frequencies biggest countries in the world of genotypes in the population, which can serve as a basis comparable to contrast the actual observations. If researchers could not make such a comparison, then the observations were meaningless.
The principle of Hardy-Weinberg is also valuable in that it teaches us that Mendelian heredity itself, there is no inherent mechanism that may lead to changes in gene frequency in populations. Such changes, when they occur, should be hanged activity of other factors such as genetic variation, natural selection, genetic drift and migration; In fact, all the factors that drive the evolution.
Born naturalist, ancient literature lover and collector of historical information. Made through the RSS RSS Subscription - records ben.hateva@gmail.com contact page on the website image Author Recent Entries How evolved the Swiss solo thing that gets the whole world? Twilight Zone categories have interesting things in the fleet service department
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