THE VARIETY OF LIVING ORGANISMS

The Cell Cycle – Mitosis

The Cell Cycle – Mitosis

Mitosis creates identical cells, each with exactly the same genetic information. In the body, it’s vital for growth and also tissue repair.

Similar to meiosis, mitosis takes place in a number of stages.

  • Prophase: DNA condenses into chromosomes. As the genetic information has been duplicated each chromosome has an identical copy of itself known as its sister chromosome. However, each chromosome in the pair is known as a chromatid although, once separated, they’re called chromosomes again. The nucleus membrane dissolves and the centrioles move to opposite poles of the cell, forming a spindle structure.
  • Metaphase: the spindle attaches to kinetochores at each pole of the cell. The chromosomes then line up in the middle of the spindle.
  • Anaphase: the sister chromosomes then separate and migrate to opposite poles of the cell.
  • Telophase: the spindle elongates and nuclear envelope for each prospective cell begins to form.
  • Cytokinesis: this is the process in which the cells physically separate. In animal cells, the cell membrane creates a cleavage furrow which pinches apart. In plant cells, a cell plate is formed which forms the new cell wall of the daughter cells.