Ribosome

In cell biology, a ribosome is an organelle composed of RNA and ribosomal proteins; which translates mRNA into a polypeptide chain (e.g., a protein).

They can be thought of as a factory that builds a protein from a set of genetic instructions. Ribosomes are found in the cytosol (the internal fluid of the cell) of all cells. . Ribosomes consist of two subunits (Fig. 1) that fit together (Fig. 2) and work as one to translate the mRNA into a polypeptide chain (Fig.3). Each subunit consists of one or two very large RNA molecules (known as ribosomal RNA or rRNA) and several smaller protein molecules.