The Hardy-Weinberg Law and Genetic Drift
Population genetics is the field of studying heredity in a population. His main assumption is a law independently formulated by two scientists, the English mathematician Hardy and the German geneticist Weinberg, named after the discoverers of the Hardy-Weinberg law.
According to this law, the frequency of alleles and genotypes is constant, that is, it does not change from generation to generation. The population to which this law applies is in a state of genetic equilibrium and does not obey the laws of evolution.
The rule formulated by Hardy and Weinberg will only work if the following conditions are met:
• a population consists of a large number of individuals - statistical rules apply only in a group of individuals with a large number;
• individuals intersect randomly within the population (panmixia) - there are no environmental and geographical restrictions, gender preferences are not taken into account, therefore, the probability of mating is the same for all individuals.;
• there are no selection mechanisms - all individuals are equally fertile, and their offspring have the same chance of survival; natural and artificial selection do not work;
• there are no mutations in the population, and the variability of organisms occurs only as a result of recombination;
• Populations are isolated from each other, which means that individuals cannot migrate between them (this prevents gene exchange).
According to the Hardy-Weinberg law, it is possible to determine the frequency of alleles and genotypes in a given population. In a population of diploid species, the specific gene of which has only two alleles: A and a:
p is the frequency of the A allele
q is the frequency of the a allele
p + d = 1
p 2 is the frequency of the dominant homozygote (genotype AA)
q 2 is the frequency of the recessive homozygote (genotype aa) 2
pq is the frequency of the Aa heterozygote
Then we can do it:
p 2 + q 2 + 2 pq = 1
In fact, all the conditions of the Hardy-Weinberg law are never fulfilled simultaneously, so natural populations are not genetically balanced and are subject to evolution.
Genetic drift
Genetic drift is a phenomenon that occurs in small populations and consists in a change in the frequency of alleles in a population. This change is the result of random events, not the effect of natural selection or mutation. The reason for the drift is the diverse reproduction of individuals, which may be the result of problems finding a reproductive partner and accidental mortality of offspring. The influence of genetic drift on the frequency of alleles is greater the smaller the population size. The effect of genetic drift may be the complete elimination of a low-frequency allele (favorable, unfavorable, or neutral) from the gene pool of a population. An example of the effects of genetic drift is the founder effect and the bottleneck effect. How to Sign Up at 1xBet Most bookmakers ask you dozens of questions before you can get into the action. We all know how much of a tedious experience this can become. At 1xBet, however, this is not the case. Here’s how to get started and register at 1xBet. It is in the 1xBet esports tab where the action really begins. Selecting the CS2 option immediately brings up dozens of leagues and matches to bet on. promo code for 1xbet to get up to $130 welcome bonus. 1xBet gives you several options to contact customer service. There’s an ever-present live chat feature, a telephone hotline as Whatsapp and email contacts.
According to this law, the frequency of alleles and genotypes is constant, that is, it does not change from generation to generation. The population to which this law applies is in a state of genetic equilibrium and does not obey the laws of evolution.
The rule formulated by Hardy and Weinberg will only work if the following conditions are met:
• a population consists of a large number of individuals - statistical rules apply only in a group of individuals with a large number;
• individuals intersect randomly within the population (panmixia) - there are no environmental and geographical restrictions, gender preferences are not taken into account, therefore, the probability of mating is the same for all individuals.;
• there are no selection mechanisms - all individuals are equally fertile, and their offspring have the same chance of survival; natural and artificial selection do not work;
• there are no mutations in the population, and the variability of organisms occurs only as a result of recombination;
• Populations are isolated from each other, which means that individuals cannot migrate between them (this prevents gene exchange).
According to the Hardy-Weinberg law, it is possible to determine the frequency of alleles and genotypes in a given population. In a population of diploid species, the specific gene of which has only two alleles: A and a:
p is the frequency of the A allele
q is the frequency of the a allele
p + d = 1
p 2 is the frequency of the dominant homozygote (genotype AA)
q 2 is the frequency of the recessive homozygote (genotype aa) 2
pq is the frequency of the Aa heterozygote
Then we can do it:
p 2 + q 2 + 2 pq = 1
In fact, all the conditions of the Hardy-Weinberg law are never fulfilled simultaneously, so natural populations are not genetically balanced and are subject to evolution.
Genetic drift
Genetic drift is a phenomenon that occurs in small populations and consists in a change in the frequency of alleles in a population. This change is the result of random events, not the effect of natural selection or mutation. The reason for the drift is the diverse reproduction of individuals, which may be the result of problems finding a reproductive partner and accidental mortality of offspring. The influence of genetic drift on the frequency of alleles is greater the smaller the population size. The effect of genetic drift may be the complete elimination of a low-frequency allele (favorable, unfavorable, or neutral) from the gene pool of a population. An example of the effects of genetic drift is the founder effect and the bottleneck effect. How to Sign Up at 1xBet Most bookmakers ask you dozens of questions before you can get into the action. We all know how much of a tedious experience this can become. At 1xBet, however, this is not the case. Here’s how to get started and register at 1xBet. It is in the 1xBet esports tab where the action really begins. Selecting the CS2 option immediately brings up dozens of leagues and matches to bet on. promo code for 1xbet to get up to $130 welcome bonus. 1xBet gives you several options to contact customer service. There’s an ever-present live chat feature, a telephone hotline as Whatsapp and email contacts.
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