The function of DNA

The function of DNA

DNA is found in the nuclei of eukaryotic cells, it is wound up so it can fit. It's wound around proteins called histones and these help to support the DNA. It's loose in the cytoplasm of prokaryotic cells and is short and circular, it isn't wound around histones. Small molecules of DNA are found in mitochondra, chloroplasts and some viruses. Evidence has also shown that DNA appeared very early in evolution.

DNA has two main functions which are replication and protein synthesis.

DNA replication

In order for cells to divide chromosomes must copy themselves. This means each daughter cell recieves an exact copy of the genetic information which is needed. The copying of DNA is called replication and it takes place in the nucleus during interphase.

• Conservative replication: the parental double helix remains intact, i.e it's conserved and a whole new double helix is made
• Semi-conservative replication: parental double helix separates into two strands, which then act as a template for the synthesis of new strands (This is the what actually occurs)
• Dispersive replication: the two new double helices contain fragments from both strands of the parental double helix

Experiments were carried out to test which of the…