Long lengths of DNA can make up sections called genes. Lots of genes make up a chromosome. We have 23 pairs of chromosomes in each cell, making 46 - 23 from each parent.
- A gene is a section of DNA, contains instructions to make a protein
- Cells make proteins by stringing amino acids in an order
- 20 amino acids used, make thousands of proteins
- Genes tell cells in what order to put the amino acids together
- DNA determines what proteins the cell produces
- Determines what type of cell it is (red blood cell, skin cell, etc)
Everyone's DNA is unique, except for identical twins and clones.
DNA fingerprinting involves cutting up a strand of someone's DNA into small sections and then separating them on a piece of card. This is used in forensic science (eg to discover whose hair was left at the crime scene) and in paternity testing.