Chronological summary of the discovery of genetic material
All living organisms have unique features, some of which are inherited and these form the basis of evolution. A body is a diversified set of functions, organized, focused and develops the capacity to reproduce its kind. A living entity never appears, but always the same from a preexisting body.
In general, all biological systems are equipped genetic continuity, which is directly related to the biochemical composition, mainly with proteins and nucleic acids DNA and RNA.
genetic material
Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the biochemical constituents, carriers of genetic information in all forms of cellular life and viruses. The discovery of the hereditary process began with the theory of pangenesis, which dates back to ancient Greece. The proposal argued that the semen, the reproductive element, consisted of particles representing all parts of the body (pangenes).
This idea was widespread in the late eighteenth century by Jean Baptiste de Lamarck, who, in his theory known as Lamarckism, postulated that the physical characteristics acquired by an individual, would be transmitted to their descendants.
The hypothesis proposed in pangenesis and some precepts of Lamarque, were accepted by most biologists of the nineteenth and mid-century, it was determined that each organism is derived from a single cell.
Nineteenth and twentieth century:In 1835 Hegel published work Aesthetics Where states that mature in a living organism there is nothing that has not already on the vine.
In 1864, the English philosopher Herbert Spencer, in his principles of biology, stated that, throughout the whole body of inherited property is determined by different physiological units, which come together to form highly complex compounds.
In 1866, Haeckel noted that the nucleus contains the chromosomes is the cellular organelle that should be the preservation and transmission of hereditary characteristics. En1892 Six years later, Weismann stated that hereditary traits were located on the chromosome. This conclusion, obtained from research conducted on the germ plasm, indicating that the sperm and eggs such as germ cells are direct descendants of the germ cells of the preceding generation and the remaining cells of the body, known as somatic cells, although derived from germ cells in turn, can not generate them.
Chromosome, as Weismann, consists of spherical bodies or ides. Each id contains determinants and each determinant is composed of biophorids, representing all of them a different character. The Weismann biophorids gene corresponds to current, ie the unit of genetic material and biological order.
The quantitative study of the transmission of hereditary characteristics was initiated in 1865 by Gregor Mendel, but Mendel’s laws came to be known until 1900, when they were rediscovered independently by Hugo de Vries, Correns and Tschermak. This was the beginning of formal genetics and each gene was assigned a specific location on the chromosome.
Schrodinger in 1944, established that small molecules from large aggregates can be built without boring repetition. Each cell is a complex organic molecule, wherein each group of atoms plays a specific individual, different to that carried out the other constituents, but essential and complementary.
Schrodinger pointed out that the atoms in an organic molecule, are joined by forces that are similar to those unions that are observed in a solid structure. Thus, the essential structure of all living things, the chromosomal fiber has the same strength that a crystal, therefore, may be referred to as an aperiodic crystal.
Despite all the research about the molecular structure related to inheritance, it was not until mid-twentieth century, around 1944, when the genetic material was identified chemically and its structure was not determined until 1953.
The system vivo is highly complex and evolving continuously, this will combine inheritance, variation and environmental action. The Research on the DNA in all living organisms has demonstrated that every living summarizes the constituent parts and sets out specific functions for each of them. All this based on biochemical information that is contained in the structures carrying the genetic information.
