The biological significance of mitosis is very high. It’s hard to even imagine for the unenlightened what role the process of simple cell division in the body plays in life. The ability of cells to divide is their most important fundamental function. Without this, the continuation of life on Earth, the increase in the populations of unicellular organisms is impossible, the development and continued existence of a large multicellular organism is impossible , sexual reproduction and the development of new life from a fertilized egg are also impossible.
The biological significance of mitosis would be much less if cell division were not the essence of most biological processes occurring on our planet. This process takes place in several stages. Each of them includes several actions inside the cell. The result of this is the mandatory multiplication of the genetic basis of one cell in two by duplication of DNA, so that subsequently the mother cell gave birth to two daughter cells.
The whole life of a cell can be concluded from the formation of a daughter to its subsequent division into two. This period is called "cell cycle" in biology.
The very first phase of mitosis is the actual preparation for cell division. The period in which cells endowed with nuclei perform direct preparation for division is called interphase. All the most important things happen in it, namely, the doubling of the DNA chain and other structures, as well as the synthesis of a large amount of protein. Thus, the chromosomes of the cells become doubled, and each half of such a double chromosome is called “chromatid”.
After interphase, the fission process itself begins - mitosis. It also passes in several steps. As a result, all doubled parts stretch symmetrically along the cell, so that after the formation of the central septum in each new cell, the same number of formed components remains.
The phases of mitosis and meiosis are similar, but in the latter (in the division of germ cells) there are two divisions, and as a result, not two, but four “daughter” cells are obtained. Also, before the second division, there is no doubling of the chromosomes, so their set in daughter cells remains half.
1. Prophase. In this phase, the centrioles of the cells are very clearly visible. They are present only in the cell of animals and humans. Plants do not have centrioles.
2. Prometaphase. At this point, the prophase ends and the metaphase begins.
3. Metaphase. At this point, the chromosomes lie on the "equator" of the cell.
4. Anaphase. Chromosomes move to different poles.
5. Telophase. One “mother” cell is divided by forming a central septum into two “daughter” cells. So cell division or mitosis ends.
The most important biological significance of mitosis is the absolutely identical division of doubled chromosomes into 2 identical parts and their placement in two “daughter” cells. Different types of cells and cells of different organisms have a varying time of the duration of division - mitosis, but on average it takes about one and a half hours. There are many factors that influence this very fragile process. Any changing environmental conditions, for example, the ambient temperature, the regime of light phases, the pressure in the environment and inside the body and cells, as well as many other factors, can significantly affect the duration and quality of the cell division process. Also, the duration of all mitosis and its individual steps can directly depend on the type of tissue in which it flows.
The biological significance of mitosis with each new discovery in the field of cytology becomes more valuable, because without this process life on the planet is impossible.