In short, translation is the synthesis of proteins by ribosomes in the cell. It follows after the process of transcription in which a molecule of mRNA is copied from DNA to produce a specific base sequence. The length and sequence of each molecule of mRNA can vary depending on what polypeptide is being produced, thus there are many different genes which cary this information in our DNA. Firstly, mRNA binds onto the small subunit of a ribosome. An initiator tRNA binds onto the mRNA, this will be on the codon AUG (start codon). Next, a second tRNA molecule with an anticodon complimentary to the next codon will bind to the ribsome. The ribsome then transfers the amino acid from the first to the second tRNA, forming a dipeptide. The ribosome then moves along the mRNA in the 5' to 3' direction whilst the first tRNA is released. Another tRNA wiht a complimentary anticodon binds on and the chain is transfered to the next tRNA. This process is repeated until a stop codon on the mRNA is reached and the completed polypeptide is released.
This process is essential in the production of proteins in the body, Insulin is an example of a peptide hormone which is made in this way. Knowledge and understanding of this mechanism has helped in the production of insulin by bacteria for use medical care such as patients with diabetes.