For unicellular or multicellular organisms, division is the only way to reproduce. One of these types of division is mitosis. Mitotic divisionIt takes place after several stages.

It is surrounded by a self-protective membrane, on the outside with organelles. cellbegins to grow from the moment it is first formed. With the development of the organelles and the nucleus within them over time, it is time to share. Agree mitotic division Why? Bride phases and characteristics Let’s take a closer look at that.

Let’s start with the basics, what is mitosis?

Mitotic divisionrefers to the process of cell division where a single cell divides resulting in two identical cells. As a synonym, it means that both cells have the same number of chromosomes and the same genetic content.

Originally, the term mitosis was only used in some cells, such as certain fungi, and in the fertilized eggs of many insects. cytokinesis It meant nuclear division, unaccompanied by cytoplasmic division. Now the term mitosis is used interchangeably with the term cell division. However, another cell division involving sex cells meiosis It is not always available because it has a form.

How does mitosis take place?

Mitosis takes place in somatic cells, especially in the nucleus. A cell is a sequence of cells that results in the formation of two identical daughter cells. mitotic goes through the event. Although these mitotic stages are the same in every asexual cell, they are different in plants. Before all mitotic events in plants, a phase called the prophase takes place.

So what are the stages of mitosis in order?

• Couple
• prophase
• prometaphase
• metaphase
• anaphase
• telephase

Couple:

Before the cell begins to divide by mitosis, DNAis copied in preparation for cell division and two identical sets of chromosomes are formed. Outside the nucleus there are two cells, each with a pair of centrioles. centrosome These structures are crucial for the cell division process. Couple It is by itself divided into 3 phases;

G1 phase is the stage before DNA is synthesized. S phase is the stage where DNA synthesis takes place. The new cell formed as a result of the previous division grows andcontinue her normal activities is the phase. In other words, ATP, RNA, protein, enzyme and organelle synthesis takes place. S phase is the stage where DNA synthesis and replication takes place. When the cell reaches the maturity of division, the command to divide comes from the nucleus thanks to the signaling molecules. The G2 phase is the phase where DNA synthesis ends, DNA replication is controlled, and prophase begins. Here too, the synthesis of ATP, RNA, protein and organelles continues.

Prophase:

Prophase occurs immediately after the S and G2 stages. Chromosomes evolve into X-shaped structures that are easily visible under the microscope. Two siblings with each chromosome containing the same genetic information of chromatid occurs. Then the chromosomes pair so that both copies of each chromosome are together. prophase Eventually, the membrane surrounding the nucleus dissolves in the cell, releasing the chromosomes. This is where the nuclear membrane begins to break down.

Prometaphase:

in prometaphase The membrane around the core is now completely disintegrated. extending from centromere microtubules reaches the chromosomes.

Metaphase:

Chromosomes are neatly arranged along the equator, the center of the cell. Microtubules pull on chromosomes with equal force. Thus, each new cell will be formed. chromosome will be able to receive.

Anaphase:

Separation of sister chromatids anaphase indicates the beginning. These sister chromatids become chromosomes of small nuclei. Sister chromatids are then separated by the mitotic spindle, which pulls one chromatid to one pole and the other to the opposite pole. At this stage, the cell checks to see if the newly formed cells each have identical chromosomes.

Telophase:

It starts with the attraction of sister chromosomes to the poles of the resulting cells. At this stage, the nuclear membrane forms around the chromosomes in the nucleus, as in the mother cell. So the chromosomes from the cytoplasm is separated.

Also in this phase the chromosomes unravel again. Mitotic spindle fibers disappear. In every daughter cell nucleolus occurs again. After all, the last stage is known as the cell cytoplasm dividing stage. cytokinesis begins. The cytokinesis phase can sometimes begin in the anaphase phase.

What are the main features of mitosis?

• It promotes the growth of the organism
• Provides cell repair
• Replaces the cell with a new one
• Regulates the cell division cycle

It ensures the growth of the organism:

An adult human is made up of billions of cells, and all the cells in the body have the same genetic component has. This genetic stability is achieved through mitosis. These cells in the body are formed by mitosis of the first cell zygote. The zygote divides through mitosis to form genetically identical daughter cells.

Provides Cell Repair:

Blows from the outside, injures cells kills or damages. These damaged or dying cells must be replaced with cells of the same type with the same genetic quality. This is achieved through mitosis.

Replaces the cell with a new one:

Let’s take blood cells as an example. Red blood cells have a lifespan of 120 days. After 120 days, it must be replaced with new cells. This one cell change enables mitosis. Likewise, skin cells are constantly replaced.

It performs the control of the cell division cycle:

The cell cycle is controlled by genes. The specific signaling molecules are G1, G2 and M at the 3 checkpoints of the cycle. to carry on smoothly offers. The cell cycle is controlled at these points by the stop and continuous signals. When the cell has reached a sufficient size at the G1 checkpoint, a continuation signal is given.

DNA damage and cell size are checked at the G2 checkpoint. If there is no problem, a continue signal is given. At the M checkpoint, the attachment of the kinetochores to the spindle fibers is checked. If there is no problem, a continue signal is given. Cell cycle control is disrupted for any reason to the formation of cancer causes. These cells do not respond to the division signals, they divide continuously and cause tumor formation and thus the development of cancer.

Let’s take a closer look at the importance of mitosis:

The balance between the nucleus and the cytoplasm is achieved by mitosis, so the shape and size of the cell constant. In multicellular organisms, a unicellular zygote develops into a multicellular embryo. By repeating the same process, the embryo eventually forms the multicellular organism. It is responsible for the transformation of the zygote into an adult. It forms reproductive organs in multicellular organisms. Reproduction in eukaryotic organism occurs through this process. (as with Chlamidomonas).

Mitosis allows for the quantitative and qualitative distribution of chromosomes in all cells of an organism. It maintains a fixed number of chromosomes in all body cells of an organism. Any wound or broken part of the organisms can be quickly transformed by mitosis. to repair can be done. Diseases such as tumors and cancer are caused by uncontrolled mitosis.

Mitosis is used to produce genetically similar offspring. For example, budding hydra and yeast, binary fission in amoeba, etc. Mitosis allows the sexually reproducing organism to grow and develop from a single cell into a sexually mature individual. This allows organisms to reproduce for generations. DNA of the cell and RNA It helps to maintain the balance between the content.