During the elongation the codon is being read in (c.) A site, A site also known as aminoacyl or acceptor site. During elongation, the site in the ribosome that represents the location where a codon is being read is the A site. This is because the purpose of the A site is to act as the acceptor for the growing protein during peptide bond formation. The P site, on the other hand, is the peptidyl site that binds to the tRNA holding the growing.