Gregor Mendel was a Capuchin friar who began his studies on the transmission of hereditary traits starting from a plant of scented pea. The ancient men noticed the resemblance between parents and children but did not know how to explain it. The most popular theory was that of blending, in which the various traits of the parents would blend into the new individual.
Mendel's Laws
Mendel studied 32 different varieties of plants and understood that every self-fertilization produced plants with the same hereditary traits, known as pure lines. He explained this relationship by hypothesizing the presence of an hereditary unit composed of two components that could or could not be manifested. This hereditary unit (gene) is composed of 2 factors (or alleles). In fertilization, the diploid cell becomes haploid, formed by one component from the mother and one from the father per pair.
Law of Segregation
Every individual has pairs of factors for each hereditary unit that separate for the formation of gametes. Mendel discovered all this without knowing about DNA and chromosomes but understanding the process of fertilization and meiosis, in addition to gametes and homologous chromosomes.
Law of Dominance
From the crossing of two individuals that differ for a pair of hereditary traits, individuals who manifest traits are obtained. The individuals of departure can be homozygous dominant or heterozygous.
Punnett Square
The Punnett square allows to know all the possible combinations of alleles of the descendants from P to F2, and allows to obtain genotypic and phenotypic ratios. It can be developed like a binomial square, where the progeny can appear in two cases: the individual is definitely homozygous (all the same color) or the individual is heterozygous (50%).
Independent Assortment Law
The alleles that form a gene separate to form gametes independently from the alleles of another gene.
Conclusion
Mendel's studies laid the foundation for the science of genetics, providing clear rules for easily replicable scientific methods. Thanks to his experiments and observations, the laws of inheritance and the functioning of heredity were clarified, offering a new understanding of the transmission of traits from one generation to the next.
