- The genome is the hereditary information carried in DNA (made of genes and the non-coding area of DNA).
- DNA is used to make mRNA in sets of 3, triplets. The matching set of 3 bases in mRNA is called a codon.
- Another type of RNA called transfer RNA (tRNA) carries the amino acids to the ribosome to be joined together to form the protein. The matching set of 3 bases in tRNA to the bases on mRNA is called the anti-codon.
- The genetic code has four bases (C,G,A,T/U) in triplets and codons (3 bases at a time). This produces 64 different combinations such as AAt, CCG etc.
- However there are only 20 different amino acids
- Therefore more than one codon is used to code for the same amino acid - this is called redundancy due to degeneracy within the genetic code.
Example