Genetic Recombination

Heredity and variability of the living world are inseparable features of living things that define the specificity of species, each species having its own assets or its own dowry hereditary genetic variability and its own capacity. The phenomenon of heredity and variability of the living world, including the human species, has aroused interest of all thinkers and it was interpreted differently, depending on the level of knowledge attained by mankind, in various epochs of its evolution. Genetic recombination is the second source of variability in the living world. Genetic recombination makes a huge genotypic and phenotypic diversity of organisms in the living world, diversity representing the potential source of survival, adaptation and evolutionary change of organisms and species.

Genetic recombination is a universal phenomenon in the living world, based on the principle of duality, which occurs at all levels of organization: at the molecular level with pairs of nitrogenous bases and at the macromolecular level called DNA recombination, by two complementary strands for each DNA molecule, between the chromosomes, two chromatids of each chromosome ready for cell division, at the cellular level between two differentiated cells with complementary sexual potential such as egg and sperm in the wide body between organs that are bilateral with symmetry duality and the population level in the differentiation of opposite sex individuals, male and female. Meiotic division provides the formation of sex cells. Chromosomal recombination is achieved by the process of crossing-over which is the mutual exchange of chromosomal segments also known as genes, between homologues recombination chromosomes, which occur in the first phase of meiotic recombination.

Genetic recombination disjunction is performed by independent pairs of chromosomes associated in bivalent chromosomes from each of the counterparts, one of maternal origin, the other of paternal origin. This occurs at the transition from metaphase I to anaphase I of the first meiotic division. Because of this genetic recombination, children do not inherit the genetic program of the mother or the father, but new combinations of genes, maternal and paternal chromosomes to separate poles, resulting constellations of genes of great diversity.