The Austrian priest and botanist Gregor Johann Mendel laid the foundations for such a science as genetics. He mathematically deduced the laws of genetics, which are now called by his name.

Johann Mendel was born on July 22, 1822 in Heisendorf, Austria. As a child, he began to show interest in the study of plants and the environment. After two years of study at the Institute of Philosophy in Olmütz, Mendel decided to enter a monastery in Brunn. This happened in 1843. During the rite of tonsure as a monk, he was given the name Gregor. Already in 1847 he became a priest.

The life of a clergyman consists not only of prayers. Mendel managed to devote a lot of time to study and science. In 1850, he decided to take the exams for a teacher's diploma, but failed, getting "A" in biology and geology. Mendel spent 1851-1853 at the University of Vienna, where he studied physics, chemistry, zoology, botany and mathematics. Upon his return to Brunn, Father Gregor nevertheless began to teach at the school, although he never passed the exam for a teacher's diploma. In 1868 Johann Mendel became abbot.

From 1856, Mendel carried out his experiments, which eventually led to the sensational discovery of the laws of genetics, in his small parish garden. It should be noted that the environment of the holy father contributed to scientific research. The fact is that some of his friends had a very good education in the field of natural science. They often attended various scientific seminars in which Mendel also participated. In addition, the monastery had a very rich library, of which, naturally, Mendel was a regular. He was very inspired by Darwin's book "The Origin of Species", but it is known for certain that Mendel's experiments began long before the publication of this work.

On February 8 and March 8, 1865, Gregor (Johann) Mendel spoke at meetings of the Natural History Society in Brunn, where he spoke about his unusual discoveries in a still unknown area (which would later become known as genetics). Gregor Mendel set up experiments on simple peas, however, later the range of experimental objects was significantly expanded. As a result, Mendel came to the conclusion that the various properties of a particular plant or animal do not just appear out of thin air, but depend on "parents". Information about these hereditary properties is transmitted through genes (a term coined by Mendel, from which the term "genetics" is derived). As early as 1866, Mendel's book Versuche uber Pflanzenhybriden (Experiments with Plant Hybrids) was published. However, contemporaries did not appreciate the revolutionary nature of the discoveries of the humble priest from Brunn.

Mendel's scientific research did not distract him from his daily duties. In 1868 he became abbot, tutor of an entire monastery. In this position, he perfectly defended the interests of the church in general and the monastery of Brunn in particular. He was good at avoiding conflicts with the authorities and avoiding excessive taxation. He was very much loved by parishioners and students, young monks.

On January 6, 1884, Father Gregor (Johann Mendel) passed away. He is buried in his native Brunn. Glory as a scientist came to Mendel after his death, when experiments similar to his experiments in 1900 were independently carried out by three European botanists who came to similar results with Mendel.

Gregor Mendel - teacher or monk?

The fate of Mendel after the Theological Institute has already been arranged. Ordained as a priest, the twenty-seven-year-old canon received an excellent parish in Old Brunn. He has been preparing for his Doctor of Divinity exams for a year now, when a major change is taking place in his life. Georg Mendel decides to change his fate rather abruptly and refuses to perform religious service. He would like to study nature and for the sake of this passion he decides to take a place in the Znaim gymnasium, where by this time the 7th grade is opening. He asks for the position of "supplement professor".

In Russia, “professor” is a purely university title, and in Austria and Germany even a first-grader mentor was called that way. The gymnasium suplent is rather, it can be translated as “ordinary teacher”, “teacher's assistant”. This could be a person who was fluent in the subject, but since he did not have a diploma, they hired him rather temporarily.

A document has also been preserved explaining such an unusual decision by Pastor Mendel. This is an official letter to Bishop Count Schafgotch from the abbot of the monastery of St. Thomas, Prelate Nappa.” Your Gracious Episcopal Eminence! By Decree No. Z 35338 of September 28, 1849, the High Imperial-Royal Land Presidium considered it a good thing to appoint Canon Gregor Mendel as a supplement at the Znaim Gymnasium. “... This canon has a God-fearing lifestyle, abstinence and virtuous behavior, his dignity is fully appropriate, combined with great devotion to the sciences ... However, he is somewhat less suitable for caring for the souls of the laity, for as soon as he finds himself at the sickbed , as from the sight of suffering, he is seized with insurmountable confusion, and from this he himself becomes dangerously ill, which prompts me to resign from him the duties of a confessor.

So, in the autumn of 1849, Canon and Supplement Mendel arrives in Znaim in order to take up new duties. Mendel receives 40 percent less than his colleagues who had diplomas. He is respected by his colleagues, his students love him. However, he teaches at the gymnasium not subjects of the natural science cycle, but classical literature, ancient languages ​​and mathematics. Need a diploma. This will allow teaching botany and physics, mineralogy and natural history. There were 2 ways to the diploma. One is to graduate from the university, the other is a shorter way - to pass in Vienna, before a special commission of the imperial ministry of cults and education, examinations for the right to teach such and such subjects in such and such classes.

Mendel's laws

The cytological foundations of Mendel's laws are based on:

Pairings of chromosomes (pairings of genes that determine the possibility of developing any trait)

Features of meiosis (processes occurring in meiosis that provide independent divergence of chromosomes with genes located on them to different pluses of the cell, and then to different gametes)

Features of the fertilization process (random combination of chromosomes carrying one gene from each allelic pair)

Scientific method of Mendel

The main patterns of transmission of hereditary traits from parents to offspring were established by G. Mendel in the second half of the 19th century. He crossed pea plants that differ in individual traits, and on the basis of the results obtained substantiated the idea of ​​the existence of hereditary inclinations responsible for the manifestation of traits. In his works, Mendel applied the method of hybridological analysis, which has become universal in the study of the patterns of inheritance of traits in plants, animals, and humans.

Unlike his predecessors, who tried to trace the inheritance of many traits of an organism in the aggregate, Mendel investigated this complex phenomenon analytically. He observed the inheritance of only one pair or a small number of alternative (mutually exclusive) pairs of traits in varieties of garden peas, namely: white and red flowers; low and high growth; yellow and green, smooth and wrinkled pea seeds, etc. Such contrasting traits are called alleles, and the terms "allele" and "gene" are used as synonyms.

For crosses, Mendel used pure lines, that is, the offspring of one self-pollinating plant, which retains a similar set of genes. Each of these lines did not show splitting of signs. It was also essential in the methodology of hybridological analysis that Mendel for the first time accurately calculated the number of descendants - hybrids with different traits, that is, he mathematically processed the results obtained and introduced the symbolism accepted in mathematics to record various crossing options: A, B, C, D and etc. With these letters he designated the corresponding hereditary factors.

In modern genetics, the following symbols are accepted for crossing: parental forms - P; hybrids of the first generation obtained from crossing - F1; hybrids of the second generation - F2, third - F3, etc. The very crossing of two individuals is indicated by the sign x (for example: AA x aa).

Of the many different traits of crossed pea plants in the first experiment, Mendel took into account the inheritance of only one pair: yellow and green seeds, red and white flowers, etc. Such crossing is called monohybrid. If the inheritance of two pairs of traits is traced, for example, yellow smooth pea seeds of one variety and green wrinkled another, then the crossing is called dihybrid. If three or more pairs of traits are taken into account, the cross is called polyhybrid.

Patterns of inheritance of traits

Alleles - denoted by the letters of the Latin alphabet, while Mendel called some signs dominant (predominant) and designated them with capital letters - A, B, C, etc., others - recessive (inferior, suppressed), which he designated with lowercase letters - a, c, c, etc. Since each chromosome (carrier of alleles or genes) contains only one of two alleles, and homologous chromosomes are always paired (one paternal, the other maternal), diploid cells always have a pair of alleles: AA, aa, Aa , BB, bb. Bb, etc. Individuals and their cells that have a pair of identical alleles (AA or aa) in their homologous chromosomes are called homozygous. They can form only one type of germ cells: either gametes with the A allele or gametes with the a allele. Individuals that have both dominant and recessive Aa genes in the homologous chromosomes of their cells are called heterozygous; when germ cells mature, they form gametes of two types: gametes with the A allele and gametes with the a allele. In heterozygous organisms, the dominant allele A, which manifests itself phenotypically, is located on one chromosome, and the recessive allele a, suppressed by the dominant, is in the corresponding region (locus) of another homologous chromosome. In the case of homozygosity, each of the pair of alleles reflects either the dominant (AA) or recessive (aa) state of the genes, which in both cases will show their effect. The concept of dominant and recessive hereditary factors, first applied by Mendel, is firmly established in modern genetics. Later, the concepts of genotype and phenotype were introduced. The genotype is the totality of all the genes that an organism has. Phenotype - the totality of all the signs and properties of the organism, which are revealed in the process of individual development of the given conditions. The concept of phenotype extends to any signs of an organism: features of the external structure, physiological processes, behavior, etc. The phenotypic manifestation of signs is always realized on the basis of the interaction of the genotype with a complex of factors of the internal and external environment.

Gregor Mendel a brief biography of the Austrian biologist and botanist is set out in this article. He is the founder of the theory of heredity, later called Mendelism after him.

Gregor Mendel biography briefly

Johann Mendel was born in 1822 into a poor peasant family in a small village in the Austrian Empire (today it is the territory of the Czech Republic).

Johann graduated from high school, then two-year philosophical courses. In 1843, Mendel entered the Augustinian monastery in Brno, where he received the priesthood and received his middle name - Gregor. Later he went to Vienna, where he spent two years studying natural history and mathematics at the university, after which he returned to the monastery in 1853. Where to do gardening and asked for a small fenced area for a garden. He devoted many years of his life to the study of genetics.

While in Vienna, Mendel became interested in the process of hybridization in plants and, in particular, in the different types of hybrid descendants and their statistical relationships. From 1856 to 1863, he experimented on peas, and as a result formulated the laws of inheritance ("Mendel's laws").

In 1865 he published the work "Experiments on plant hybrids", in which he outlined the basic laws of heredity. Handel himself was sure that he had made the greatest discovery. But scientists ridiculed his ideas, and he left his scientific studies and became the abbot of the monastery.

MENDEL, GREGOR JOHANN(Mendel, Gregor Johann) (1822–1884), Austrian biologist, founder of genetics.

Born July 22, 1822 in Heinzendorf (Austria-Hungary, now Ginchice, Czech Republic). He studied at the Heinzendorf and Lipnik schools, then at the district gymnasium in Troppau. In 1843 he graduated from philosophical classes at the University of Olmutz and took the vows as a monk at the Augustinian monastery of St. Thomas in Brunn (Austria, now Brno, Czech Republic). He served as an assistant pastor, taught natural history and physics at the school. In 1851-1853 he was a volunteer at the University of Vienna, where he studied physics, chemistry, mathematics, zoology, botany and paleontology. Upon his return to Brunn, he worked as a teacher's assistant in a secondary school until 1868, when he became abbot of the monastery. In 1856, Mendel began his experiments on crossing different varieties of peas that differ in single, strictly defined characteristics (for example, in the shape and color of seeds). Accurate quantitative accounting of all types of hybrids and statistical processing of the results of experiments that he conducted for 10 years allowed him to formulate the basic laws of heredity - the splitting and combination of hereditary "factors". Mendel showed that these factors are separated and do not merge or disappear when crossing. Although when two organisms with contrasting traits (for example, yellow or green seeds) are crossed, only one of them appears in the next generation of hybrids (Mendel called it “dominant”), the “disappeared” (“recessive”) trait reappears in subsequent generations. (Today Mendel's hereditary "factors" are called genes.)

Mendel reported the results of his experiments to the Brunn Society of Naturalists in the spring of 1865; a year later, his article was published in the proceedings of this society. No questions were asked at the meeting, and the article received no response. Mendel sent a copy of the article to K. Negeli, a well-known botanist, an authoritative specialist on the problems of heredity, but Negeli also failed to appreciate its significance. And only in 1900 the forgotten work of Mendel attracted everyone's attention: three scientists at once, H. de Vries (Holland), K. Correns (Germany) and E. Chermak (Austria), having carried out their own experiments almost simultaneously, were convinced of the validity of Mendel's conclusions . The law of independent splitting of traits, now known as Mendel's law, marked the beginning of a new direction in biology - Mendelism, which became the foundation of genetics.

Mendel himself, after unsuccessful attempts to obtain similar results when crossing other plants, stopped the experiments and until the end of his life was engaged in beekeeping, gardening and meteorological observations.

Among the works of the scientist - Autobiography(Gregorii Mendel autobiography iuvenilis, 1850) and a number of articles, including Experiments on plant hybridization (Versuche über Pflanzenhybriden, in Proceedings of the Brunn Society of Naturalists, vol. 4, 1866).

MENDEL (Mendel) Gregor Johann (1822-84), Austrian naturalist, monk, founder of the doctrine of heredity (Mendelism). Applying statistical methods to analyze the results of hybridization of pea varieties (1856-63), he formulated the laws of heredity.

MENDEL (Mendel) Gregor Johann (July 22, 1822, Heinzendorf, Austria-Hungary, now Ginchice - January 6, 1884, Brunn, now Brno, Czech Republic), botanist and religious figure, founder of the doctrine of heredity.

Difficult years of teaching

Johann was born as the second child of a peasant family of mixed German-Slavic origin and middle income, to Anton and Rosina Mendel. In 1840, Mendel completed six classes at the gymnasium in Troppau (now the city of Opava) and the following year entered the philosophical classes at the university in Olmütz (now the city of Olomouc). However, the financial situation of the family during these years worsened, and from the age of 16, Mendel himself had to take care of his food. Not being able to constantly endure such stress, Mendel, after graduating from philosophical classes, in October 1843, entered the Brynn Monastery as a novice (where he received the new name Gregor). There he found patronage and financial support for further studies. In 1847 Mendel was ordained a priest. At the same time, from 1845, he studied for 4 years at the Brunn Theological School. Augustine Monastery of St. Thomas was the center of scientific and cultural life in Moravia. In addition to a rich library, he had a collection of minerals, an experimental garden and a herbarium. The monastery patronized school education in the region.

monk teacher

As a monk, Mendel enjoyed teaching physics and mathematics at a school in the nearby town of Znaim, but did not pass the state teacher certification exam. Seeing his passion for knowledge and high intellectual abilities, the abbot of the monastery sent him to continue his studies at the University of Vienna, where Mendel studied as a volunteer for four semesters in the period 1851-53, attending seminars and courses in mathematics and the natural sciences, in particular, the course of the famous physics K. Doppler. A good physical and mathematical background helped Mendel later in formulating the laws of inheritance. Returning to Brunn, Mendel continued teaching (he taught physics and natural history at a real school), but the second attempt to pass the certification of a teacher was again unsuccessful.

Experiments on pea hybrids

From 1856, Mendel began to carry out in the monastery garden (7 meters wide and 35 meters long) well-thought-out extensive experiments on crossing plants (primarily among carefully selected varieties of peas) and elucidating the patterns of inheritance of traits in the offspring of hybrids. In 1863 he completed the experiments and in 1865 at two meetings of the Brunn Society of Naturalists he reported the results of his work. In 1866, in the proceedings of the society, his article "Experiments on Plant Hybrids" was published, which laid the foundations of genetics as an independent science. This is a rare case in the history of knowledge when one article marks the birth of a new scientific discipline. Why is it considered so?

Work on plant hybridization and the study of the inheritance of traits in the offspring of hybrids was carried out decades before Mendel in different countries by both breeders and botanists. The facts of dominance, splitting and combination of characters were noticed and described, especially in the experiments of the French botanist C. Naudin. Even Darwin, crossing varieties of snapdragons that differ in flower structure, obtained in the second generation a ratio of forms close to the well-known Mendelian splitting of 3: 1, but saw in this only a "capricious play of the forces of heredity." The variety of plant species and forms taken in the experiments increased the number of statements, but reduced their validity. The meaning or "soul of facts" (the expression of Henri Poincaré) remained vague until Mendel.

Quite different consequences followed from the seven-year work of Mendel, which rightfully constitutes the foundation of genetics. Firstly, he created the scientific principles for describing and studying hybrids and their offspring (what forms to take in crossing, how to analyze in the first and second generations). Mendel developed and applied an algebraic system of symbols and designations for features, which was an important conceptual innovation. Secondly, Mendel formulated two basic principles, or the law of inheritance of traits in a number of generations, allowing predictions to be made. Finally, Mendel implicitly expressed the idea of ​​discreteness and binarity of hereditary inclinations: each trait is controlled by a maternal and paternal pair of inclinations (or genes, as they were later called), which are transmitted to hybrids through parent germ cells and do not disappear anywhere. The inclinations of traits do not affect each other, but diverge during the formation of germ cells and then freely combine in descendants (the laws of splitting and combining traits). The pairing of inclinations, the pairing of chromosomes, the double helix of DNA - this is the logical consequence and the main path for the development of genetics of the 20th century based on the ideas of Mendel.

Great discoveries are often not immediately recognized.

Although the works of the Society, where Mendel's article was published, were received by 120 scientific libraries, and Mendel sent an additional 40 prints, his work received only one favorable response - from K. Negeli, professor of botany from Munich. Negeli himself was engaged in hybridization, introduced the term "modification" and put forward a speculative theory of heredity. However, he doubted that the laws revealed on peas are universal and advised to repeat the experiments on other species. Mendel respectfully agreed with this. But his attempt to replicate the results obtained on peas on the hawk, with which Negeli worked, was unsuccessful. It wasn't until decades later that it became clear why. Seeds in the hawk are formed parthenogenetically, without the participation of sexual reproduction. Other exceptions to Mendel's principles were also observed, which were interpreted much later. This is part of the reason for the cold reception of his work. Since 1900, after the almost simultaneous publication of articles by three botanists - H. De Vries, K. Correns and E. Cermak-Seisenegg, who independently confirmed Mendel's data with their own experiments, there was an instant explosion of recognition of his work. 1900 is considered the birth year of genetics.

A beautiful myth has been created around the paradoxical fate of the discovery and rediscovery of Mendel's laws that his work remained completely unknown and that three rediscoverers came across it only by chance and independently, 35 years later. In fact, Mendel's work was cited about 15 times in the 1881 summary of plant hybrids and was known to botanists. Moreover, as it turned out recently when analyzing the workbooks of K. Correns, back in 1896 he read Mendel's article and even made an abstract of it, but at that time he did not understand its deep meaning and forgot.

The style of conducting experiments and presenting the results in Mendel's classic article makes it very likely that the English mathematical statistician and geneticist R. E. Fisher came up with in 1936: Mendel first intuitively penetrated the "soul of facts" and then planned a series of many years of experiments in such a way that illumined his idea came out in the best way. The beauty and rigor of the numerical ratios of forms during splitting (3:1 or 9:3:3:1), the harmony in which they managed to put the chaos of facts in the field of hereditary variability, the ability to make predictions - all this internally convinced Mendel of the universal nature of the facts he found on pea laws. It remained to convince the scientific community. But this task is as difficult as the discovery itself. After all, knowing the facts does not mean understanding them. A major discovery is always associated with personal knowledge, feelings of beauty and wholeness based on intuitive and emotional components. It is difficult to convey this non-rational kind of knowledge to other people, because efforts and the same intuition are needed on their part.

The fate of Mendel's discovery - a delay of 35 years between the very fact of the discovery and its recognition in the community - is not a paradox, but rather the norm in science. So, 100 years after Mendel, already in the heyday of genetics, a similar fate of non-recognition for 25 years befell B.'s discovery of mobile genetic elements. And this despite the fact that, unlike Mendel, by the time of her discovery she was a highly respected scientist and a member of the US National Academy of Sciences.

In 1868, Mendel was elected abbot of the monastery and practically retired from scientific studies. His archive contains notes on meteorology, beekeeping, and linguistics. On the site of the monastery in Brno, the Mendel Museum has now been created; a special journal "Folia Mendeliana" is published.

Gregor Mendel(Gregor Johann Mendel) (1822-84) - Austrian naturalist, botanist and religious figure, monk, founder of the doctrine of heredity (Mendelism). Applying statistical methods to analyze the results of hybridization of pea varieties (1856-63), he formulated the laws of heredity.

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Gregor Johann Mendel Biology teacher Kuzyaeva A.M. Nizhny Novgorod

Gregor Johann Mendel (July 20, 1822 - January 6, 1884) Austrian naturalist, botanist and religious figure, Augustinian monk, abbot, founder of the doctrine of heredity (Mendelism). Applying statistical methods to analyze the results of hybridization of pea varieties, he formulated the laws of heredity - Mendel's laws - which became the basis of modern genetics.

Johann Mendel was born on July 20, 1822 into a peasant family of Anton and Rosina Mendel in the small rural town of Heinzendorf (Austrian Empire, now the village of Hinchitsy, Czech Republic). The date July 22, which is often given in the literature as the date of his birth, is in fact the date of his baptism. House of Mendel

He began to show interest in nature early, already as a boy working as a gardener. After graduating from high school, he studied for two years at the philosophical classes of the Olmutz Institute, in 1843 he took the vows of the Augustinian monastery of St. Thomas in Brunn (now Brno, Czech Republic) and took the name Gregor. From 1844 to 1848 he studied at the Brünn Theological Institute. In 1847 he became a priest. Starobrnensky Monastery

He independently studied many sciences, replaced the absent teachers of the Greek language and mathematics in one of the schools, but did not pass the exam for the title of teacher. In 1849-1851 he taught mathematics, Latin and Greek at the Znojmo gymnasium. In the period 1851-1853, thanks to the rector, he studied natural history at the University of Vienna, including under the guidance of Unger, one of the first cytologists in the world. Franz Unger (1800-1870) University of Vienna

From 1856, Gregor Mendel began to conduct well-thought-out extensive experiments in crossing plants (primarily among carefully selected varieties of peas) and elucidating the patterns of inheritance of traits in the offspring of hybrids in the monastery garden (7 * 35 meters). A separate card (10,000 pieces) was entered for each plant.

In 1863, he completed the experiments, and on February 8, 1865, at two meetings of the Brunn Society of Naturalists, he reported the results of his work. In 1866, in the proceedings of the society, his article "Experiments on Plant Hybrids" was published, which laid the foundations of genetics as an independent science.

Mendel ordered 40 separate prints of his work, almost all of which he sent to major botanical researchers, but received only one favorable response - from Karl Naegeli, professor of botany from Munich. He suggested repeating similar experiments on the hawk, which he himself was studying at that time. Later it will be said that Naegeli's advice delayed the development of genetics for 4 years ... Carl Naegeli (1817-1891)

Kingdom: Plants Department: Angiosperms Class: Dicotyledonous Order: Asteraceae Family: Asteraceae Genus: Hawkweed Mendel tried to repeat the experiments on the hawk, then bees. In both cases, the results obtained by him on peas were not confirmed. The reason was that the fertilization mechanisms of both hawks and bees had features that science was not yet aware of at that time (reproduction through parthenogenesis), and the crossing methods used by Mendel in his experiments did not take into account these features. In the end, the great scientist himself lost faith that he had made a discovery.

In 1868, Mendel was elected abbot of the Starobrnensky Monastery and was no longer engaged in biological research. In 1884 Mendel died. Since 1900, after the almost simultaneous publication of articles by three botanists - H. De Vries, K. Correns and E. Cermak-Seisenegg, who independently confirmed Mendel's data with their own experiments, there was an instant explosion of recognition of his work. 1900 is considered the birth year of genetics. H. De Vries H. De Vries E. Cermak

Significance of the works of Gregor Mendel Mendel created the scientific principles for the description and study of hybrids and their offspring (what forms to take in crossing, how to analyze in the first and second generation). Developed and applied an algebraic system of symbols and designations of features, which was an important conceptual innovation. He formulated two basic principles, or the law of inheritance of traits in a number of generations, which make it possible to make predictions. Mendel implicitly expressed the idea of ​​discreteness and binarity of hereditary inclinations: each trait is controlled by a maternal and paternal pair of inclinations (or genes, as they were later called), which are transmitted to hybrids through parent germ cells and do not disappear anywhere. The inclinations of traits do not affect each other, but diverge during the formation of germ cells and then freely combine in descendants (the laws of splitting and combining traits).

Illustration of Mendel's laws

On January 6, 1884, Gregor Johann Mendel died. Shortly before his death, Mendel said: “If I had to go through bitter hours, then I must acknowledge with gratitude that there were many more beautiful, good hours. My scientific works have given me a lot of satisfaction, and I am convinced that not much time will pass - and the whole world will recognize the results of these works. The Mendel monument in front of the memorial museum in Brno was built in 1910 with funds raised by scientists from all over the world.