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BIOGRAPHIES OF GREAT SCIENTISTS
Mendel Gregor Johann. Biography of a scientist
Directory / Biographies of great scientists
The Austro-Hungarian scientist Gregor Mendel is rightfully considered the founder of the science of heredity - genetics. The work of the researcher, "rediscovered" only in 1900, brought posthumous fame to Mendel and served as the beginning of a new science, which was later called genetics. Until the end of the seventies of the XX century, genetics basically moved along the path laid down by Mendel, and only when scientists learned how to read the sequence of nucleic bases in DNA molecules, did they begin to study heredity not by analyzing the results of hybridization, but based on physicochemical methods. Gregor Johann Mendel was born in Heinzendorf in Silesia on July 20, 1822 into a peasant family. In elementary school, he showed outstanding mathematical abilities and, at the insistence of his teachers, continued his education at the gymnasium in the small nearby town of Opava. However, there was not enough money in the family for the further education of Mendel. With great difficulty they managed to scrape together to complete the gymnasium course. The younger sister Teresa came to the rescue: she donated the dowry accumulated for her. With these funds, Mendel was able to study for some more time at university preparation courses. After that, the family's funds dried up completely. The way out was proposed by professor of mathematics Franz. He advised Mendel to enter the Augustinian monastery in Brno. It was headed at that time by Abbot Cyril Napp, a man of broad views who encouraged science. In 1843, Mendel entered this monastery and received the name Gregor (at birth he was given the name Johann). Four years later, the monastery sent the twenty-five-year-old monk Mendel as a teacher to a secondary school. Then, from 1851 to 1853, he studied natural sciences, especially physics, at the University of Vienna, after which he became a teacher of physics and natural science at a real school in the city of Brno. His teaching activity, which lasted fourteen years, was highly appreciated by both the leadership of the school and the students. According to the memoirs of the latter, he was considered one of the most beloved teachers. For the last fifteen years of his life, Mendel was the abbot of the monastery. From his youth, Gregor was interested in natural science. More of an amateur than a professional biologist, Mendel was constantly experimenting with various plants and bees. In 1856 he began the classic work on hybridization and analysis of the inheritance of traits in peas. Mendel worked in a tiny, less than two and a half acres, monastery garden. He sowed peas for eight years, manipulating two dozen varieties of this plant, different in flower color and seed type. He did ten thousand experiments. With his zeal and patience, he brought to considerable amazement the partners who helped him in necessary cases - Winkelmeyer and Lilenthal, as well as the gardener Maresh, who was very prone to drinking. If Mendel gave explanations to his assistants, they could hardly understand him. Slowly life flowed in the monastery of St. Thomas. Gregor Mendel was also slow. Persistent, observant and very patient. Studying the shape of seeds in plants obtained as a result of crossings, in order to understand the patterns of transmission of only one trait ("smooth - wrinkled"), he analyzed 7324 peas. He examined each seed with a magnifying glass, comparing their shape and making notes. With Mendel's experiments, another countdown began, the main distinguishing feature of which was, again, Mendel's introduction of a hybridological analysis of the heredity of individual traits of parents in offspring. It is difficult to say what exactly made the naturalist turn to abstract thinking, to digress from bare figures and numerous experiments. But it was precisely this that allowed the modest teacher of the monastic school to see a complete picture of the study; to see it only after having had to neglect the tenths and hundredths due to the inevitable statistical variations. Only then did the alternative traits literally "marked" by the researcher reveal something sensational to him: certain types of crossing in different offspring give a ratio of 3:1, 1:1, or 1:2:1. Mendel turned to the work of his predecessors for confirmation of a hunch that had flashed through his mind. Those whom the researcher considered to be authorities came at different times and each in his own way to a general conclusion: genes can have dominant (suppressive) or recessive (suppressed) properties. And if so, Mendel concludes, then the combination of heterogeneous genes gives the same splitting of features that is observed in his own experiments. And in the very ratios that were calculated using his statistical analysis. "Checking the harmony of algebra" of the changes taking place in the resulting generations of peas, the scientist even introduced letter designations, marking the dominant state with a capital letter, and the recessive state of the same gene with a lower case letter. Mendel proved that each trait of an organism is determined by hereditary factors, inclinations (later they were called genes), transmitted from parents to descendants with germ cells. As a result of crossing, new combinations of hereditary traits may appear. And the frequency of occurrence of each such combination can be predicted. Summarized, the results of the scientist's work look like this: • all hybrid plants of the first generation are the same and show the trait of one of the parents; • among hybrids of the second generation, plants appear with both dominant and recessive traits in a ratio of 3:1; • two traits behave independently in the offspring and occur in all possible combinations in the second generation; • it is necessary to distinguish between traits and their hereditary inclinations (plants exhibiting dominant traits may latently bear the makings of recessive traits); • The combination of male and female gametes is random in relation to the inclinations of what traits these gametes carry. In February and March 1865, in two reports at meetings of the provincial scientific circle, called the Society of Naturalists of the city of Brno, one of its ordinary members, Gregor Mendel, reported the results of his many years of research completed in 1863. Despite the fact that his reports were rather coldly received by the members of the circle, he decided to publish his work. She saw the light in 1866 in the works of a society called "Experiments on plant hybrids." Contemporaries did not understand Mendel and did not appreciate his work. For many scientists, the refutation of Mendel's conclusion would mean nothing less than the assertion of their own concept, which said that an acquired trait can be "squeezed" into the chromosome and turned into an inherited one. As soon as they did not crush the "seditious" conclusion of the modest abbot of the monastery from Brno, venerable scientists invented all sorts of epithets in order to humiliate and ridicule. But time has decided in its own way. Yes, Gregor Mendel was not recognized by his contemporaries. Too simple, unsophisticated seemed to them a scheme in which, without pressure and creaking, complex phenomena, which, in the minds of mankind, were the foundation of an unshakable pyramid of evolution, fit in. In addition, there were vulnerabilities in Mendel's concept. So, at least, it seemed to his opponents. And the researcher himself, too, because he could not dispel their doubts. One of the "culprits" of his failures was a hawk. The botanist Karl von Negeli, a professor at the University of Munich, after reading Mendel's work, suggested that the author check the laws he discovered on a hawk. This small plant was Naegeli's favorite subject. And Mendel agreed. He spent a lot of energy on new experiments. Hawkweed is an extremely inconvenient plant for artificial crossing. Very small. I had to strain my eyesight, and it began to worsen more and more. The offspring obtained from crossing the hawk did not obey the law, as he believed, correct for everyone. Only years after biologists established the fact of a different, non-sexual reproduction of the hawk, the objections of Professor Negeli, Mendel's main opponent, were removed from the agenda. But neither Mendel nor Negeli himself, alas, were already dead. The greatest Soviet geneticist Academician B. L. Astaurov, the first president of the All-Union Society of Geneticists and Breeders named after N. I. Vavilov, spoke very figuratively about the fate of Mendel’s work: "The fate of Mendel's classical work is perverse and not alien to drama. Although he discovered, clearly showed and to a large extent understood very general laws of heredity, the biology of that time had not yet matured to realize their fundamental nature. Mendel himself with amazing insight foresaw the general significance of the laws found on peas and obtained some evidence of their applicability to some other plants (three kinds of beans, two kinds of levkoy, corn, and night beauty).However, his persistent and tedious attempts to apply the regularities found to the crossing of numerous varieties and species of hawk did not justify hopes and failed completely. happy was the choice of the first object (peas), just as unsuccessful was the second. Only much later, already in our century, it became clear that the peculiar patterns of inheritance of traits in the hawk are an exception that only confirms the rule. In Mendel's time, no one could suspectthat the crossings of hawkweed varieties he attempted did not actually take place, since this plant reproduces without pollination and fertilization, in a virgin way, by means of the so-called apogamy. The failure of painstaking and strenuous experiments that caused almost complete loss of vision, the burdensome duties of a prelate that fell on Mendel and advanced years forced him to stop his favorite studies. A few more years passed, and Gregor Mendel passed away, not anticipating what passions would rage around his name and what glory it would eventually be covered with. Yes, glory and honor will come to Mendel after death. He will leave life without unraveling the secrets of the hawk, which did not "fit" into the laws of uniformity of hybrids of the first generation and the splitting of characters in the offspring that he derived. It would have been much easier for Mendel if he had known about the work of another scientist Adams, who by that time had published a pioneering work on the inheritance of traits in humans. But Mendel was not familiar with this work. But Adams, on the basis of empirical observations of families with hereditary diseases, actually formulated the concept of hereditary inclinations, noticing the dominant and recessive inheritance of traits in humans. But botanists had not heard of the doctor's work, and the doctor probably had so much practical medical work that there was simply not enough time for abstract reflection. In general, one way or another, but geneticists learned about Adams's observations only when they began to seriously study the history of human genetics. Not lucky and Mendel. Too early the great explorer reported his discoveries to the scientific world. The latter was not yet ready for this. Only in 1900, having rediscovered Mendel's laws, the world was amazed at the beauty of the logic of the researcher's experiment and the elegant accuracy of his calculations. And although the gene continued to be a hypothetical unit of heredity, doubts about its materiality were finally dispelled. Mendel was a contemporary of Charles Darwin. But the article of the Brnov monk did not catch the eye of the author of The Origin of Species. One can only guess how Darwin would have appreciated Mendel's discovery if he had read it. Meanwhile, the great English naturalist showed considerable interest in the hybridization of plants. Crossing different forms of snapdragon, he wrote about the splitting of hybrids in the second generation: "Why is this so. God knows ..." Mendel died on January 6, 1884, the abbot of the monastery where he conducted his experiments with peas. Unnoticed by his contemporaries, Mendel, however, did not hesitate at all in his rightness. He said: "My time will come." These words are inscribed on his monument, installed in front of the monastery garden, where he set up his experiments. The famous physicist Erwin Schrodinger believed that the application of Mendel's laws is tantamount to the introduction of the quantum principle in biology. The revolutionary role of Mendelism in biology became more and more evident. By the early thirties of our century, genetics and the laws of Mendel underlying it had become the recognized foundation of modern Darwinism. Mendelism became the theoretical basis for the development of new high-yielding varieties of cultivated plants, more productive livestock breeds, and useful types of microorganisms. Mendelism gave impetus to the development of medical genetics ... A memorial plaque has now been erected in the Augustinian monastery on the outskirts of Brno, and a beautiful marble monument to Mendel has been erected next to the front garden. The rooms of the former monastery, overlooking the front garden where Mendel conducted his experiments, have now been turned into a museum named after him. Here are collected manuscripts (unfortunately, some of them perished during the war), documents, drawings and portraits related to the life of the scientist, books that belonged to him with his notes in the margins, a microscope and other tools that he used, as well as those published in different countries. books dedicated to him and his discovery. Author: Samin D.K.
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