Mitosis – one of the most important stages for the cell 20th November 2023 – Tags: cell, Mitosis, zygote
One of the most important skills for a cell is the ability to divide. We know two cell divisions – meiosis and mitosis. Today we will delve into the second one – mitosis.
What is mitosis?
Mitosis is the process by which one cell divides into two identical daughter cells. During this process, chromosomes are replicated and segregated to create two identical cell nuclei, which will then participate in cell division. Occurs after the G2 phase, followed by cytoplasmic division after separation of the nucleus.
The role of mitosis for the body:
- Ensuring genetic stability – by producing daughter cells that are genetically identical and uniform to the parent cells, mitosis helps maintain and maintain the genetic stability of a specific population
- Growth – by producing a large number of cells, the body can grow
- Replacing and regenerating new cells – by creating new cells, it is possible to replace damaged and worn out cells.
- Asexual reproduction – reproduction by cell division in the process of meiosis occurs, for example, during the budding of hydras and yeasts
- Thanks to mitosis, a constant number of chromosomes in the body is maintained
- Mitosis ensures equal distribution of chromosomes in each daughter cell
- Mitosis is needed for the development of the zygote
Stages of mitosis:
- Interphase – Just before mitosis begins, the cell spends most of its time in a phase called interphase. During it, DNA synthesis takes place. During interphase, other phases of the cell cycle also occur – G1 phase, S phase and G2 phase
- Prophase – during this stage, the genetic material condenses to create compact mitotic chromosomes composed of two chromatids attached to the centromere. The end of prophase is determined when the assembly of the mitotic spindle, microtubules and protein components of the cytoplasm is initiated.
- Prometaphase – during this stage, the nuclear envelope disappears. Thanks to this, microtubules are able to stretch from the centromere to the chromosome. They then attach to kinetochores, which will allow the cell to move the chromosome
- Metaphase – during this stage, microtubules begin to attract chromosomes, causing them to arrange themselves in a line in the center of the cell, called the metaphase plate
- Anaphase – during this stage, sister chromatids divide. Then, the sister chromatids become the chromosomes of the daughter nuclei. The chromosomes are then pulled poleward by fibers attached to the kinetochores of each chromosome
- Telophase – chromosomes that have gathered at the two poles of the cell begin to form an undifferentiated mass. A nuclear envelope begins to form around the resulting mass. The nucleolus, Golgi bodies, and ER complex that disappeared after prophase begin to reappear