Translation occurs in living cells. Explain how translation is carried out, from the initiation stage onwards.

The mRNA was transcribed, (or copied) form a piece of DNA and it holds the information that is needed for protein synthesis. mRNA is read and the amino acids are eventually put together in a chain (polypeptide) that makes up a protein - and this is this process that is called translation. The process is important because it is responsible for creating the proteins that make up most cells.

Protein translation happens in an organelle in the cell called a ‘ribosome’. The first stage of translation, the initiation stage, is that the mRNA binds to a small subunit of the ribosome. tRNA connects mRNA codons to the amino acids they encode. One end of each tRNA has a sequence of three nucleotides called an anticodon, which can bind to specific mRNA codons. tRNA molecule binds to the ribosome, but its anticodon must match the codon on the messenger RNA, which is done through complementary base pairing. These two form a hydrogen bond together. Other tRNA molecule then bonds to the mRNA. Two tRNA molecules can bind at once. Then the two amino acids, that the tRNA brought with it, form a peptide bond. The first tRNA then detaches from the ribosome and the second one takes its place. The ribosome moves along the mRNA to the next codon so that another tRNA can bind. Again, a peptide bond is formed between the amino acids and the process continues. Eventually, a polypeptide chain is formed, and this is the basis of protein synthesis.