3.24b Mitosis 2

1. The cell which will undergo the process of mitosis will have to copy its chromosomes. 
2. The process of copying chromosomes is called DNA replication. In this process each chromosome undergoes a copying process to form an identical copy of itself, with the same genes. 
3. These pairs of copies are held together through a bonding in the centre region called the centromere. 
4. These pairs are referred to as a pair of chromotids 
5. The process of DNA replication takes place in the nucleus while its still intact. We cannot see the process. 
6. This is known as the interphase of the cell cycle. It is during this resting stage of the cycle during which the chromosomes are copied.