; Heizendorf today Hynčice, now the Czech Republic, 1822 - Brno, Brno today, id., 1884) Austrian biologist . His father was a veteran of the Napoleonic wars and his mother, the daughter of a gardener. After a childhood marked by poverty and hardship, in 1843 Johann Gregor Mendel entered the Augustinian monastery Königskloster, near Brno, where he took the name of Gregor and was ordained priest in 1847. He lived in the abbey of St. Thomas (Brno), and to continue the teaching career, was sent to Vienna, where he received his doctorate in mathematics and science (1851).
Mendel in 1854 became assistant professor at the Royal School of Brno, and in 1868 was appointed abbot of the monastery, following which definitively abandoned scientific research and is devoted exclusively to the tasks of their role .
The core of his work, which began in 1856 from crossing experiments with peas made in the monastery garden allowed him to discover the three laws of inheritance and Mendel's laws, by which it is possible to describe the mechanisms of inheritance and were explained later by the father of modern experimental genetics, the American biologist Thomas Hunt Morgan (1866 - 1945).
In the eighteenth century had already developed a number of important studies on plant hybridization, among which were those carried out by Kölreuter, W. Herbert, CC Sprengel and A. Knight, and by the nineteenth century, and Sageret Gärtner (1825). The culmination of all this work was done by, first, of C. Naudin (1815-1899) and, on the other, Gregor Mendel, who arrived Naudin far.
The three laws discovered by Mendel are stated as follows: the first, when you cross two pure strains of the same species, the offspring are all equal and can resemble either parent or any of them, the second states that , crossing each other hybrids of the second generation, the offspring were divided into four parts, one of which resembles her grandmother, another of his grandfather and the other two as their parents, and finally, the third law concludes that In the case of the two varieties differ in starting in two or more characters, each is transmitted in accordance with the first law, regardless of others.
developed the fundamental principles that today is the modern science of genetics. Mendel demonstrated that heritable traits are carried in discrete units that are inherited separately in each generation. These discrete units, which Mendel called elements, are today known as genes.
Mendel presented his experiments in 1865.
At that time, scientific knowledge was walking by:
The cell theory is commonly accepted.
already described the major organelles visible with optical microscopy.
He had published The Origin of Species that Darwin presented natural selection as a mechanism of transmission of certain characters.
Mendel's experimental method
The value and utility of any experiment depends on the choice of material suitable for the purpose for which it is used.
Mendel reasoned that an organism suitable for genetic experiments should have:
1. a number of different features, easily studied with two or three different phenotypes.
2. self-fertilize and plant should have a flower structure that limits accidental contact, fast growing and large number of descendants.
3. The descendants of self-fertilizing plants should be fertile.
First Law Mendel
Statement of the law This law is also called the Law of the uniformity of the first generation hybrids (F1). , Said that when crossed two varieties of purebred individuals both (homozygous) for a given character, all the first generation hybrids are equal.
Mendel's Second Law
Wording of the law â A Mendel's second law is also called separation or disjunction of alleles.
Mendel's Third Law
Wording of the law to this law is known as the independent inheritance of characters, and refers to if it is covering two different characters. Each of them is transmitted following the previous laws regardless of the presence of another character.
taken from: http://www.biotech.bioetica.org/ap1.htm and http://www.biografiasyvidas.com/biografia/m/mendel.htm
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