ribosomes
Last reviewed 01/2018
Ribosomes are composed of ribosomal RNA derived from nuclear DNA. They are particulate structures found:
- on the surface of the rough endoplasmic reticulum, often joined together by strands of messenger RNA - polyribosomes
- free within the cytoplasm - polysomes
They function in protein synthesis by:
- acting as a site for the junction of messenger RNA and transfer RNA
- catalyzing the formation of a peptide bond in the growing peptide chain
- ensuring the correct site of initiation and termination of the peptide chain