Please explain Mitosis

Background knowledge

DNA - carry the genetic code that determines characteristics of an organism

Chromosomes - made from long DNA molecules, many genes all coiled up into a chromosome. A healthy person will have 23 pairs of chromosomes.

Genes - a section of DNA that codes for a protien

Mitosis is all about replication of DNA

Cells reproduce in two ways - Mitosis and Meiosis.

remeber the difference

Mitosis - Cellular reproduction (making new cells), growth (gowing tissue), repair (replace damaged tissue), and asexual reproduction.

Meiosis - To create genetic diversity for sexual reproduction. 

Stages

1. In the parent (original) cell, chromosomes make identical copies of themselves so there are 46 chromosomes. 

2. They line up along the centre, and then the pairs break apart and move to opposit ends of the cell

3. A split is made in the middle of the cell. Two daughter cells form with identical chromosomes to the parent cell. Each cell will have 26 chromosomes which will later replicate back to 46.

These two daughter cells are genetically identical to the original cell. They may simply create new tissue, or could be the start of a new organism.

See image for a diagram for the steps. http://www.bbc.co.uk/staticarchive/6e72c0727b01ab432efaadf3e4a262e1a7a1acfa.gif