<P> Ribosomal ribonucleic acid (rRNA) is the RNA component of the ribosome, and is essential for protein synthesis in all living organisms . It constitutes the predominant material within the ribosome, which is approximately 60% rRNA and 40% protein by weight, or 3 / 5 of ribosome mass . Ribosomes contain two major rRNAs and 50 or more proteins . The ribosomal RNAs form two subunits, the large subunit (LSU) and small subunit (SSU). The LSU rRNA acts as a ribozyme, catalyzing peptide bond formation . rRNA sequences are widely used for working out evolutionary relationships among organisms, since they are of ancient origin and are found in all known forms of life . </P> <P> The ribosomal RNAs complex with proteins to form two subunits, the large subunit (LSU) and small subunit (SSU). During translation, mRNA is sandwiched between the small and large subunits, and the ribosome catalyzes the formation of a peptide bond between the two amino acids that are contained in the rRNA . </P>

Where is ribosomal rna found in the cell