Function of Mitosis

Mitosis is the process of cell division. There are three reasons why cells divide mitotically:

  1. Cell Replacement
  2. Growth
  3. Asexual Reproduction

1) Cell Replacement

Cells divide in order to produce new cells that replace damaged, dying or lost cells. Your skin, for example, consists of millions of cells that protect your body against damage and pathogens1. The cells on the surface slough off after a while, for example, when you scratch yourself or because of other forms of abrasion2. The cells lost need to be replaced by new cells. These cells are produced in deep layers of your skin through mitotic cell division.

2) Growth

lzimmermann-zellteilung-embryo.jpg

We all started out as a single cell. When your mother's egg cell and your father's sperm cell fused, this single cell was created. Then the cell divided mitotically often enough to produce the millions of cells in your body. The picture to the right (AOK Mediendienst) shows an image of a human embryonic cell that has already divided a few times. Each of these cells differentiates to fulfill a special function in your body. Some cells, for example, will become part of your heart, while others will develop into bone cells. All the cells of your body work together in tissues and organs in very complex ways so that you can speak, learn, eat, play and perform all the other activities that are part of your daily life.

3) Asexual Reproduction

lzimmermann-cilliate.jpg

Sometimes, mitosis even functions to produce a whole new organism. To the left, you see a microscopic picture of an organism that consists of a single cell (author of the picture: The Alpha Wolf). This organism, called a cilliate, reproduces by mitotic cell division: it simply divides in half. Thus, the new cell has a single parent cell and is genetically identical with its parent. Asexual reproduction occurs in single-celled organisms, but also in plants and more complex animals. If you clip part of a plant off, for example, it can develop into a whole new plant. Sea stars can also reproduce asexually. If a sea star loses an arm, for example, this arm can regenerate into a whole new sea star.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License