Mitosis, also known as mitosis and caryomytosis, is a concept related to biology which represents the cell division process indirect by the differentiation of chromosomes and their distribution into two equal parts. It is the normal process of dividing the cell nucleus in two that precedes cell division.
It usually occurs as a form of homeotypic cell division, which has the function of transmitting to daughter cells the genetic information of the chromosomes of the nucleus without any quantitative or qualitative alteration, in what is different gives meiosis.
At interface, the period between two nuclear divisions, the doubling of chromosomes and identical replication of DNA take place. Mitosis can take a few minutes or take several hours.
Normally, a cell division is followed by another cell division. A multiplication of the number of chromosomes may appear when a longitudinal division takes place, repeated in the chromosomes, without the subsequent distribution of child chromosomes and formation of child nuclei (endomitosis). This type of nuclei with multiple chromosomes is called
polyploids.See also the meaning of Fetal develop.
Mitosis Phases
Mitosis is divided into several phases:
- Prophase: the amorphous chromatin condenses to form chromosomes, which are composed of two chromatids, united only in the region of the centromeres; the nuclear membrane and nucleolus begin to dissolve and fibrous masses appear at the poles that constitute the miotic apparatus or achromatic spindle. In it, the chromosomes are inserted through the centromere, which start their displacement towards the equatorial plate;
- Metaphase: the chromosomes, greatly shortened due to a spiraling retraction of the chromosomes, join in the center of the cell, forming the equatorial plate;
- Anaphase: the identical halves of the chromosomes (now called the child chromosomes) separate towards the poles under the influence of the achromatic spindle; a new longitudinal division of the chromosomes often becomes visible in preparation for the next nuclear division. The child chromosomes cluster at the poles;
- Telophase: the child chromosomes clustered at the poles surround themselves with a new cell membrane and the nucleolus reappears; in the end, the fully unfolded chromosomes become invisible.
Mitosis and Meiosis
Mitosis and meiosis are two cell division processes carried out in the human body and there are some differences between the two processes.
Mitosis occurs in somatic cells and there is no reduction in the number of chromosomes, while meiosis occurs in germ cells and the number of chromosomes in the daughter cell is half the number of the cell mom.
A cell that has gone through the process of mitosis can undergo mitosis again, whereas a cell produced by meiosis cannot go through this process again.
The two cells generated by mitosis are genetically the same. The four cells generated by meiosis, on the other hand, are genetically different from each other and also differ from the mother cell.
Read more about eukaryotic cell.