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The damaged skin will get replaced with new cells when we have an injury on your skin. This replacement of new cells is happening because of the cell division process called as Mitosis. A different type of cell division occurs during reproduction which enables the formation of offspring called Meiosis.
  • New cells are formed in an organism to grow, replace cell (old, dead, injured) and form gametes during sexual reproduction.
  • Cell division is a process of formation of new cells from the pre-existing cells.
All living things are made up of cells. There are two significant classifications of cell in plants and animals.
  • Somatic cells or vegetal cells
  • Reproductive cells
These are of two types.
  • Mitosis
  • Meiosis
Mitosis or Mitotic cell division
It is the kind of cell division where cell divides can produce twogenetically identical daughter cells from the dividing cells of the mother cell.
Mitosis division occurs in almost all the body's cells called somatic cells which includes eyes, skin, hair, and muscle cells. In animals, mitotic cell division only takes place in the diploid somatic cells, whereas plant shows mitotic division happens in both haploid and diploid cells. Mitotic cell division is also called an equational division. In this, the number of chromosomes in parents and offspring's remain the same. Each daughter cell has the same chromosome number as that of a mother cell.
 
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Mitosis division
Meiosis or Meiotic cell division
This cell division occurs in the sexually reproducing cells. This kind of cell division forms the gametes. The male (sperm) and female (egg) gamete, both are haploid in nature, unite to form zygote (diploid cell) after fertilization give rise to offspring (young ones). When a cell divides by meiosis, it forms four new cells instead of two.
The process of meiosis happens in two stages, i.e. meiosis-I and meiosis-II. In meiosis-I, the germ cells divide into two daughter cells that have only half the number of chromosomes compared to mother germ cells. In contrast to meiosis-I, meiosis-II resembles a normal mitosis.
 
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Meiosis division
  
Important!
In the next topic, we will be discussing in detail cell division.