Can genetic recombination change gene frequencies in a population?

In nature, genetic mutations, genetic recombination, and natural selection all affect changes in gene frequencies. The change of gene frequency is essentially the evolutionary process of organisms, and genetic mutations provide raw materials for evolution.

If biological mating is random and free, each individual has an equal chance of mating with other individuals of the opposite sex in the population, and the offspring do not die, etc., then genetic recombination does not change the gene frequency of the population. But in fact, this is the ideal condition, which does not exist in nature. Individual mating between organisms is not free, and not every individual has an equal chance of mating with other individuals within the same population.

Some individuals have many chances of mating, while others don't. For example, there are many opportunities for the king monkey in the monkey group to mate with the female monkeys in the monkey group, and the chances of mating in other male monkeys are reduced, so genetic recombination will cause a lot of opportunities for a certain gene to be passed on due to the unequal mating opportunity, and the chance for other genes to be passed on is reduced, which will cause changes in the gene frequency of the population.

Under the absolute ideal conditions, that is, each individual has an equal chance of mating, and there is no migration in and out. Suppose that the frequency of a is x, and a is y=1-x, it is easy to prove that the frequency of a and a is unchanged, aa=x2 aa=2xy aa=y2 total genes 2(2*(x+y)2), a is (2*x2+2xy) 2=x, unchanged.

Not really, because no matter how recombined, the number and variety of alleles are constant. What I have to say at the same time is that the recombinant genotype is naturally eliminated or accumulated, resulting in a change in frequency, but this is already considered a natural selection.

No, only genetic mutations alter the gene frequencies of a population.

Hardy-Weinberg's law, nothing will change without migration drift or something.

In the textbook, the conditions are no migration, no genetic mutation, no genetic mutation, no natural predators, and random mating.

Of course, that's ideal, but it's not that coincidental in reality.

And the case of random mating is not very likely.

You just remember it in high school knowledge, unchanged.

In reality, change.

The above is true, genetic recombination cannot be changed.

No. Only the rate of phenotypic can be changed.

Not necessarily.

The two cases in the diagram are very different. Both statements are true.

Figures 1 and 2 are about the change that says "never look back", apparently the gene frequency corresponding to one of the phenotypes under some natural selection.

There has been a significant increase and accounts for the vast majority of the population. This is indeed an evolutionary process (but note that it does not necessarily mean new speciation, but it is clear that the new population is at least a subpopulation to the original population (if there is one).

Figure 3 also points out"Directional change".is the essence of evolution. In the case of other factors,Changes in gene frequencies within populations are commonplace

For example, it is possible that individual genes die directly because there are very few individuals, and directly because there are no offspring due to bad luck, but this process is not called evolution, but genetic drift.

Dead genes are not lost by natural selection).

Gene frequencies of the population.

Refers to the ratio of a certain gene.

In general, gene frequencies do not change, but if a mutation occurs, a gene is recombined.

This can lead to changes in gene frequencies.

Factors that affect the gene frequency of a population must change the number of genes, including: gene mutations, chromosomal variations, natural selection, genetic drift, etc., these factors can cause changes in the number of genes, and thus can affect the gene frequency of the population.

The gene frequencies for populations are calculated as follows:

Suppose there are two alleles A and A on a locus in a diploid organism, and assuming that there are n individuals in the population, and the number of individuals in the three genotypes of AA, AA, and AA are N1, N2, and N3 respectively, then the frequencies of gene A and the frequencies of AA genotypes in the population are respectively

Frequency of a gene = total number of a genes (total number of a genes + total number of a genes) = 2n1 + n2 2n or n1 n + n2 2n.

Frequency of aa genotype = number of individuals of aa genotype Total number of this diploid population = n1 n.

The calculated relationship between gene frequency and genotype frequency is derived from the above:

Frequency of gene a = n1 n + 1 2·n2 n = frequency of aa genotype + frequency of 1 2aa genotype. For example, 30% of a population is AA, 60% is AA, and 10% is AA

Calculate the frequencies of genes a, a. [Analysis] the frequency of gene A is 30% + 1 2 60% = 60% The frequency of gene A is 10% + 1 2 60% = 40% [Answer] 60% 40%.

Conclusion: The sum of the frequencies of a pair of alleles in a population is equal to 1, and the sum of the frequencies of genotypes in a population is also equal to 1Changes in gene frequencies lead to changes in the gene pool of populations, so biological evolution is essentially a process of changes in gene frequencies in populations.

Gene frequency refers to the ratio of a gene to the number of alleles in a population's gene pool. The frequency of a particular gene in a population can be estimated from the genotype frequency.

Gene frequency refers to the proportion of a gene to the total number of alleles in a population's gene pool. The sum of the frequencies of the different genes at a certain locus and the frequencies of the various genotypes in a population is equal to 1.

For a population, the gene frequency of the population is ideally stable from generation to generation, but under natural conditions, it is affected by genetic mutation, genetic recombination, natural selection, migration and genetic drift, and the gene frequency of the population is constantly changing, so that the organisms continue to develop and evolve.

Therefore, it is useful to understand the evolution of a population by calculating the gene frequencies of that population. Ideally, a population is one that is in genetic equilibrium, following Hardy Weinberg's law of equilibrium.

Genetic equilibrium refers to the fact that in a population of great random free mating, under the conditions of no mutations, no natural selection and migration, the gene frequencies and genotype frequencies of the population are stable and unchanged from generation to generation, and remain balanced.

For populations living in nature, the ideal conditions are not possible to exist at the same time, and the gene frequencies of the population cannot be balanced, but are constantly changing and developing.

This unbalanced population often uses data obtained by sampling surveys to calculate its gene frequencies, which can be divided into two types according to the location of genes.

It's impossible, but it's okay to do it the other way around. If you are in high school, it is recommended that you understand the formula I wrote next with you to avoid confusion.

Suppose there are two alleles A and A on a locus in a diploid organism, and assuming that there are n individuals in the population, and the number of individuals in the three genotypes of AA, AA, and AA are N1, N2, and N3 respectively, then the frequencies of gene A and the frequencies of AA genotypes in the population are respectively

Frequency of a gene = total number of a genes (total number of a genes + total number of a genes) = 2n1 + n2 2n or n1 n + n2 2n.

Frequency of aa genotype = number of individuals of aa genotype Total number of this diploid population = n1 n.

The relationship between gene frequency and genotype frequency is deduced from the above: the frequency of gene a = n1 n + 1 2·n2 n = frequency of aa genotype + frequency of 1 2aa genotype.