What is the significance of Mitosis?

Mitosis is a very important process in eukaryotic organisms. It is a type of cell division in which a diploid (2n) mother cell divides to form two genetically identical diploid daughter cells. It occurs in somatic (body) cells and also in diploid germ cells (before meiosis begins). Mitosis maintains the same number of chromosomes in daughter cells as in the parent cell. This division is highly regulated and accurate so that each new cell gets a full and equal set of genetic material.

The significance of mitosis can be explained under the following points:

1. Genetic Stability and Chromosome Number Maintenance:

This is the most basic and important function of mitosis. It ensures that every daughter cell receives the same number and exact copy of chromosomes as the parent cell. For example, if a human somatic cell with 46 chromosomes divides by mitosis, both daughter cells will also have 46 chromosomes. This helps maintain genetic stability across tissues and organs and ensures organismal identity is preserved during growth and repair.

2. Growth of Multicellular Organisms:

Mitosis is the reason why a single-cell zygote develops into a multicellular body. All cell multiplication during embryonic development and postnatal body growth occurs through mitosis. It increases the number of cells, which helps in tissue formation, organ development, and body size increase in both plants and animals.

3. Tissue Repair and Replacement:

When body tissues are injured or old cells die, new cells are needed to repair or replace them. Mitosis produces genetically identical new cells that restore tissue structure and function. For example, healing of wounds, replacement of skin cells, and renewal of red blood cells from bone marrow all depend on mitosis.

4. Asexual Reproduction in Lower Organisms:

In many unicellular and simple multicellular organisms like Amoeba, Paramecium and Hydra, mitosis is used for asexual reproduction. It allows production of offspring without gametes and all daughter organisms are clones of the parent. This helps in rapid multiplication in favourable conditions.

5. Maintenance of Proper Cell Size and Function:

As cells grow larger, their efficiency decreases because the surface area to volume ratio becomes less favourable. Mitosis helps divide large cells into smaller daughter cells, keeping the ratio in balance. This supports better exchange of nutrients and waste and keeps cellular metabolism normal.






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