MITOSIS
What is Mitosis?
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When your hair, fingernails or other cells in your body grow, that growth is through the process of mitosis. If you have an injury, and your body undergoes repairs, that repair is also done through mitosis. Mitosis is the process of a parent cell dividing into two identical daughter cells. For example, if your skin is cut, existing skin cells divide to form additional skin cells.
The actual division of the cell happens pretty quickly. Most of the time a cell is in a state of interphase - and it is during this state that the cell creates a second set of chromosomes. Once two sets of chromosomes have been created, the cell divides quickly through the stages of prophase, metaphase, anaphase, and telephase. The last stage is cytokinesis which is the process when the cell actually divides into two new cells. |
https://www.youtube.com/watch?v=AhgRhXl7w_g
Phases of Mitosis |
Interphase - The resting stage. DNA is replicated during this stage.
Prophase -
Prophase -
- The chromosomes condense and become visible
- The centrioles form and move toward opposite ends of the cell ("the poles")
- The nuclear membrane dissolves
- The mitotic spindle forms
- Spindle fibers from each centriole attach to each sister chromatid at the kinetochore
- The Centrioles complete their migration to the poles
- The chromosomes line up in the middle of the cell ("the equator")
- Spindles attached to kinetochores begin to shorten.
- This exerts a force on the sister chromatids that pulls them apart.
- Spindle fibers continue to shorten, pulling chromatids to opposite poles.
- This ensures that each daughter cell gets identical sets of chromosomes
- The chromosomes decondense
- The nuclear envelope forms
- Cytokinesis reaches completion, creating two daughter cells
- The chromosomes decondense
- The nuclear envelope forms
- Cytokinesis reaches completion, creating two daughter cells