ABSTRACT
This chapter begins by very briefly recalling the biosynthesis of informational macromolecules DNA and messenger RNA and, as a result, the building of proteins. Proteins are formed by condensation of amino acids. DNA is an extremely long chain, the links of which are located at four different recurring subunits, the mononucleotides. The information contained in DNA must first be transcribed to a chemical messenger. The latter is a ribonucleic acid named messenger RNA (mRNA). Messenger RNA has a chemical structure very similar to that of DNA. The complete mRNA diffuses into the cytoplasm from the nucleus and attaches to the ribosomes and the protein synthesis occurs on the surface of these ones. The protein biosynthesis is by far the most elaborate biosynthetic mechanism known. It is the reason why it seems interesting to us to mention very briefly its steps before finishing this book by considering the biological information.
