BY1 BIOLOGY - MITOSIS

Interphase is the stage when the cell is carrying out it's normal activity. Examples of this is:

• Chromosomes replicate
• Organelles are produced
• ATP synthesis occurs
• Protein synthesis occurs
• DNA is doubled

Prophase is the first stage during mitosis.

•  The chromosomes become visible due to the chromatin condensing.
• Centrioles move to the opposite pole and start to form spindles
• The nuclear envelope disintegrates
• The nucleolus disappears.

This is the second stage of mitosis.

• The chromosomes arrange themselves at the equator of the cell
• The spindle fibres attach themselves to the centromere.

This is the third stage of mitosis.

• The spindle fibres contract and seperate the sister chromatids and move them to opposie poles
• They are now called sister chromosomes

This is the final stage of mitosis.

• The spindle fibres break down
• The nuclear envelope re-forms and the nucleolus reappears. 
• The chromosomes uncoil and lenghten to form chromatin

At the end of telophase the cell splits (cytokinesis) to form two identicle daughter cells

• Repair and replace cells and tissues
• It is important in the growth of organisms
• Asexual reproduction e.g. plants
• Genetic stability - produces identicle offspirng
• Two identicle daugher cells
• Diploid daughter cells produced.