Ribosome protein synthesis. Illustration of a protein (green chain) being produced in a cell by a unit known as a ribsome. This process is also known as translation. Ribosomes consist of two subunits composed of protein and ribosomal ribonucleic acid (rRNA). They read the sequence of mRNA (messenger ribonucleic acid) and translate it into a string of amino acids, the building blocks of proteins. The terminal end of the protein chain (bottom right) is known as the N-terminus, consisting of an amine group (NH2). For this artwork with labels, see image C023/8737.