The role of mitosis is to produce identical daughter cells for growth and the asexual reproduction of cells.
In Mitosis, chromosomes go through interphase, prophase, metaphase and anaphase.
1)Interphase
- The cell prepares to divide, and DNA is replicated by semi-conservative replication. There are now two copies of every chromosome.
- Organelles are also replicated
- More ATP is produced to be used in cell division
2)Prophase
-The nuclear envelope and nucleus break down, and subsequently disappear. Chromosomes are left floating in the cytoplasm.
- The chromosomes coil more tightly (becoming shorter and fatter). They can be seen with an optical microscope.
- Small protein bundles called centrioles move to opposite poles of the cell for mitotic spindle formation.
3)Metaphase
- the chromosomes line up along the equator of the cell (mid line) and attach to the spindle fibres via centromeres
-at this stage, the chromosomes are maximally condensed
4)Anaphase
- The chromosomes break into two chromatids. The sister chromatids separate at the centromere.
-The spindles contract and pull the chromatids to each pole of the cell.
5)Telophase
- The chromatids reach opposite poles and decondense, becoming chromosomes again.
- Nuclear envelopes form around the chromosomes so there are now two nuclei
- The cytoplasm splits and two daughter cells are formed- identical to the original and to each other
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