Meiosis

The main difference between Meiosis and Mitosis is that in Meisosis, a single cell divides twice to produce four cells containing half the original amount of genetic materials (i.e. number of chromosomes).

An example of meiotic cell division occurs in sex cells.

Sex cells are commonly known as sperm cells in males, and egg cells in females.

 

A microscope image of a cell undergoing meiosis forming four daughter cells. 

Meiosis occurs in 8 steps (or stages):

  1. Prophase I. --- The chromosomes condense, and the nuclear envelope breaks down
  2. Metaphase I. --- Pairs of homologous chromosomes (that have the same structure) move to the equator (along the diameter) of the cell.
  3. Anaphase I.--- Homologous chromosome move to the opposite ends (poles) of the cell
  4. Telophase I and Cytokinesis. --- Chromosomes gather around the poles and the cytoplasm is forced to divide
  5. Prophase II. --- Chromosomes form new spindles
  6. Metaphase II. --- Chromosomes move towards the equatr and line-up
  7. Anaphase II. --- Centromeres divides forcing the cell to pinch and split as chromatids move to the opposite poles again
  8. Telophase II and Cytokinesis. -- A nuclear membrane fors around each new sets of chromosomes and the cytoplasm breaks apart into two identical lobes