Is a recombination of alleles on homologous chromosomes a genetic recombination?

This question tests the concept and causes of genetic recombination, and only tests students' ability to understand the basic concepts of biology.

Genetic recombination refers to the recombination of genes that control different traits during the sexual reproduction of organisms. The premise is that during sexual reproduction, there are two causes of occurrence: the free combination of non-allelic genes on non-homologous chromosomes, and the cross-exchange of non-sister chromatids on homologous chromosomes.

Answer: D and A are not strictly stated, so the correct answer is D.

Summary. An allele is a gene that is located at the same position on the homologous chromosome that controls a pair of relative traits, but the gene at the same location on the homologous chromosome is not necessarily an allele, or it may be the same gene A chromosome group refers to a group of non-homologous chromosomes in a cell, which are different in morphology and function, but carry all the information that controls the growth, development, inheritance, and variation of an organism The characteristics of the chromosome set are that it does not contain homologous chromosomes and does not contain alleles

Is the same position on a homologous chromosome necessarily an allele? Is it possible that they are the same gene? Why?

An allele is a gene that is located at the same position on the homologous chromosome that controls a pair of relative traits, but the gene at the same location on the homologous chromosome is not necessarily an allele, or it may be the same gene A chromosome group refers to a group of non-homologous chromosomes in a cell, which are different in morphology and function, but carry all the information that controls the growth, development, inheritance, and variation of an organism The characteristics of the chromosome set are that it does not contain homologous chromosomes and does not contain alleles

Why the same location genes on homologous chromosomes may be alleles or may be identical genes.

It's clear that it can be the same person, or it can be said to be a different person.

The same people are the same genes? Different people are waiting? Why?

You have the same genes as your relatives, can you have the same genes as other children? It's not the same.

Is the gene mutation the cause of the allele?

Genetic mutations are usually serious illnesses and interest rates rise.

Can you explain that clearly?

The general mutation is the y-body. The X body has never changed.

First, the allele is located on the homologous chromosome.

2. Explanation of terms: Alleles refer to genes located in the same position of a pair of homologous chromosomes that control different forms of the same trait.

3. Extended content:

1. Different alleles produce changes in genetic traits such as hair color or blood type. Alleles control the dominant recessive relationship and genetic effects of relative traits, and alleles can be divided into different classes.

2. In an individual, one form of allele (dominant) can be expressed more than other forms (recessive). For example, the locus of the human Rh blood group gene is in the 3rd region 5 band of the short arm of chromosome 1, and RH and RH in the same position of two chromosome 1 are a pair of alleles.

Alleles can be located on the same chromosome.

An allele is a gene located at the same location on a pair of homologous chromosomes that controls the different morphologies of a trait.

By definition, alleles are located on homologous chromosomes, at least originating from homologous chromosomes.

However, taking into account individual differences in chromosomal variation, such as translocation of non-homologous chromosome segments, it is possible to distribute alleles between non-homologous chromosomes.

a. Genes with the same position on the same pair of homologous chromosomes are not necessarily alleles, but may also be the same genes, a is wrong;

b. Allele refers to a gene that controls relative traits in the same position of a pair of homologous chromosomes, b correct;

c. The allele is on the homologous chromosome, not on the two chromatids of the same chromosome, c is wrong;

d. The allele is on the homologous chromosome, not on the two chromatids of one chromosome, d is wrong

Non-allelic genes: genes located at different locations on homologous chromosomes or on non-homologous chromosomes.

The result of swapping alleles is genetic recombination between non-alleles. For example, B and B are swapped, and the sister monomer is AB before the swap, and AB after the swap. This is called genetic recombination. BB is an allele, and AA and BB are non-alleles.

Each of several non-allelic genes has only a partial effect on the phenotype of the same trait, and such genes are called additive genes or polygenes. In the accumulation of genes, each gene has only a small part of the phenotypic effect, so it is also called a microgene effect. In contrast to micro-genes, a single gene determines the genes of a trait.

Summary. This is a problem of genetic linkage.

Usually two pairs of alleles are located on the same pair of homologous chromosomes, linked to each other, and can be considered a pair of genes. If B and C are on the same pair of chromosomes, there are only three alleles of B and C, including BBCC, BBCC, and BBCC, and if you consider A, there are 9.

If we also consider the cross-swapping of homologous non-sister chromatids, that is, b, b, c, and c can also be genetically recombined, the genotype of the progeny is 3*3*3=27.

Both pairs of heterozygous alleles are located in two pairs of homology chromosomes, how to cross and interchange, how to swap the genotypes of the offspring A and A, it is not a genetic recombination. The problems encountered are all two hypothetical alleles on a pair of homologous chromosomes.

This is a problem of gene linkage, usually two pairs of alleles are located on the same pair of homologous chromosomes, linked to each other, and can be regarded as a pair of genes. For example, B and C are on a pair of homologous chromosomes, and there are only three types of alleles such as BBCC, BBCC, and BBCC, and if you consider the book A, there are 9 kinds. If we also consider the cross-swapping of homologous non-sister chromatids, that is, b, b, c, and c can also be genetically recombined, the genotype of the progeny is 3*3*3=27.

I'm talking about two pairs of alleles located on two pairs of homologous chromosomes, undergoing cross-swapping.

Cross-swapping occurs between homologous chromosomal non-allelic genes that are prematurely rounded. If the two pairs of AABB genes are on the same pair of chromosomes, there may be two gametes (without cross-swapping) between the two pairs of genes: ab, ab, or ab, ab (depending on whether ab is on a chromosome or ab on a chromosome). It is also possible to produce four gametes (with cross-swaps) ab, ab, ab, ab, ab If cross-swapped, the gametes will definitely produce a new genotype after fertilization.