Translation: elongation.

  1. The anticodon of an incoming tRNA base-pairs with the complementary codon in the A site.

  2. A peptide bond is formed between the new amino acid in the A site and the growing polypeptide in the P site.

  3. The ribosome translocates the tRNA in the A site to the P site.

  4. The empty tRNA in the P site is moved to the E site and released. The mRNA moves the next codon into the A site.