A change in one base of DNF in a chromosome is not considered a chromosomal variation?

Dear, these two concepts are particularly easy to mix.

Gene mutation refers to a change in the molecular structure of a gene, that is, a change in the order of the deoxynucleotides in the gene, resulting in a change in genetic information. The frequency of genetic mutations is low, but it can produce new genes, which is important for the evolution of organisms. Genetic mutations occur because DNA is duplicated due to internal and external factors.

The classic example is sickle cell anemia. Genetic mutation is the theoretical basis of mutation breeding.

Chromosomal variation is a change in the number or structure of chromosomes. The focus is on the change in numbers. The concept of the chromosome group is important to understand.

There are no homologous chromosomes and no alleles in a chromosome set, but the genetic information contained in a chromosome set is a complete set of genetic information required for ontogeny, that is, a genome is often called. For diploid organisms, all the chromosomes in the gamete are a set of chromosomes. Individuals with an even number of chromosomes are generally of childbearing potential, but individuals with an odd number of chromosomes are highly infertile, such as monoploid and triploid.

These are two different concepts, there is no relationship between who belongs to whom, these two are equal, remember that chromosomal variation becomes more than genetic mutation, and a change is a paragraph...

Chromosomal variation refers to changes in the structure and number of chromosomes, and all variations about DNA are genetic mutations.

When the number of chromosomes changes (missing, increases) or the structure of chromosomes changes, the genetic information changes, which brings about a change in the traits of the organism's offspring, which is chromosomal variation. It is a type of heritable variation. Depending on the cause of variation, it can be divided into two categories: structural variation and quantitative variation.

Play the game and play crazy - -

The change in the base is usually a genetic mutation, okay?

Not necessarily.

First of all, it is necessary to clarify the concept that the so-called gene is the base sequence that contains genetic information.

Chromosomal variations include:

1. Deletion refers to the loss of a segment on a chromosome and the gene it carries2The same segment is added to the repeating chromosome.

3.Inversion is the reversal of the internal segment of a chromosome, resulting in the reversal of the original genetic order of that segment.

4.Translocation is when a segment of one chromosome is transferred to another non-homologous chromosome, and the change in chromosomes does not necessarily affect the change in genes, such as an increase in chromosomes, where the original gene remains unchanged but only increases the number of genes.

Upstairs is absolutely right.

Supplements: 1 There are two types of chromosome variation: chromosome number variation and structural variationStructural variation: deletion.

Increase inversion. Changes in the chromosome structure mentioned above, such as ectopy, can change the number or order of genes arranged on chromosomes.

Number variation: multiplies or decreases in the form of a set of chromosomes.

Increase or decrease of individual chromosomes.

What else don't you understand?

Does chromosomal variation necessarily cause changes in gene structure? Why --- first clarify the concept that a gene is a sequence of bases that contain genetic information. Chromosomal changes do not necessarily affect gene changes, for example, chromosomes increase, the original gene remains the same, but only increases the number of genes.

Genetic mutations generally do not cause chromosomal variations.

Analysis: 1A genetic mutation is a change in a gene caused by the addition, deletion, or replacement of base pairs in a DNA molecule.

It is a variation at the molecular level and can be a change in one or more base pairs in a gene. Gene mutations cause changes in the structure of genes, resulting in the creation of new genes, but the number of genes remains the same.

2.Chromosomal variation includes chromosomal structure and number variation, and chromosomal structural variation is variation at the cellular level.

Genetic mutations and chromosomal variations are two different levels of variation.

Analysis: Chromosomal variation, such as the "inversion" in chromosome structural variation, is only the reversal of the position of the gene, but the structure has not changed.