Genes
For a long time considered as part of the gene for the hereditary material (one), which provides the development of a particular trait of an organism. But how genes function remained unclear. In 1945, George Beadle and E. Tatum hypothesis was formulated, which can be expressed by the formula "one gene - one enzyme". Later it was shown that many proteins, enzymes have a quaternary structure (consisting of several simple proteins (polypeptide chains, polypeptides)), encoded by different genes. Therefore, the formula that reflects the relationship between gene and trait was somewhat transformed: "One gene - one polypeptide". Thus, the gene is a function of the elementary unit of hereditary material. This means that a fragment of DNA corresponding to a particular gene and determining, by the contained biological information, the possibility of a specific trait is more functionally indivisible. Under the sign of the unit to understand the morphological, physiological, bi...