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Replication of DNA
The cells that make up organisms are always derived from existing cells by process of division. Cell
division occurs in two ways:
1. Nuclear division: this is a process by which a nucleus divides. There are two types of
2. Cell division:it follows nuclear division and is the process by which the whole cell divides.
Before the nucleus divides its DNA must be replicated. This is done to ensure that all daughter
cells have the genetic information to produce the enzymes and other proteins that are needed.
Semi conservative replication is the name given to the method of DNA duplication. Before
semi-conservative replication can take place four requirements must be fulfilled:
1. The four nucleotide must present
2. Both strand of DNA molecules must act as template for the attachment of these
3. DNA polymerisation must be present also to catalyse the reaction
4. Source of chemical energy is required to drive the process