List two essential roles of ribosomes during translation

Two essential roles played by ribosomes during translation are: .
(i) One of the ribosomal RNA (rRNA, 23S in prokaryotes) acts as a peptidyl transferase ribozyme for the formation of peptide bonds.
(ii) The mRNA and charged tRNAs are attached to ribosomal sites. Thus, these provide sites for the attachment during protein synthesis.