What country was the biologist Mendel from?

Gregor Mendel (1822-1884) was born on July 22, 1822, into a peasant family near Silesia, Austria. He grew up as a hobby gardener, and due to the difficulties of his family, he did not finish university and became an academician at a monastery in Boulogne. he obtained the priesthood in 1847. With the financial support of a friend, he furthered his studies at the Faculty of Science of the University of Vienna in 1850, and in the summer of 1853 he returned to the monastery in Boulogne as a teacher of flora and fauna at the period school. Combining his teaching with experimental work on hybridization of plants, he finally discovered the laws of heredity and presented his findings at the Brno Natural Science Society in 1865, but they were buried and not rediscovered until the beginning of the 20th century, thus confirming Mendel's position in genetics. Basic information Name: Mendel

Birth and death: July 22, 1822

Zodiac sign: Cancer

Birthplace: Austria

Description: Mendel is the father of modern genetics, is the founder of this important biological discipline. 1865 discovery of the hereditary rate of fixation. Childhood experience Mendel Mendel's father loved gardening, is a fruit tree cultivation grafting connoisseur, left and right farmers often come to him for advice. John grew up under the influence of his father learned to do all kinds of farm work, and fruit tree grafting developed a strong interest.　　Once he asked his father, "Dad, how is it that a tiny scion of a good species can grow into a thick manly branch and sweet-smelling fruit, even though all the nutrients are supplied by an inferior rootstock?"　　"Son, I don't know why! But it is true. Greater than the power of sustenance is the nature of the tree, that nature which people call 'heredity,' I believe!" The father answered John's question from the knowledge he had.　　Young Mendel listened in silence and was lost in thought: 'The nature of trees', 'heredity', what was that all about? He kept murmuring. Childhood experience of grafting and biological activities organized in the small school, these biological hereditary phenomena in Mendel's young mind took deep root, which greatly influenced him to become a world-famous, great biologist who discovered the laws of heredity. Career Mendel Mendel was born into a poor family of fruit farmers in Silesia, Austria-Hungary, and had gained a great deal of experience in this area as he had often helped his family care for their fruit trees and helped keep bees for the school. After his sister gave up her inheritance in order to pay for his high school education, the young Mendel entered a convent in order to study science without burdening his parents and sisters, as well as to receive a good education, which also gave him the opportunity to systematically study modern natural science at the University of Vienna. All this laid a solid foundation for his later discoveries. After graduating from the university, Mendel taught in a local church-run high school, teaching natural science. In 1843, at the age of 21, Mendel entered a convent, served as a teacher of natural science in a nearby senior high school, and later went to the University of Vienna for further study, where he was subjected to a fairly systematic and rigorous scientific education and training, which laid a solid foundation for his later scientific practice. Mendel realized after long contemplation that it was even more important to understand the mechanisms that make hereditary traits constant from generation to generation.

Shortly after returning to Brunn from the University of Vienna, Mendel began an eight-year experiment with peas. Mendel began by getting 34 varieties of peas from a number of seed dealers, from which he selected 22 varieties for his experiments. They all had some kind of stable traits that could be distinguished from each other, such as tall stems or short stems, round material or wrinkled family, gray seed coat or white seed coat, and so on.

Mendel observed, counted, and analyzed the traits and numbers of peas from different generations in great detail by growing these peas by hand. Utilizing such experimental methods required great patience and rigor. He loved his research work so much that he often pointed out the peas to guests who came to visit and said with great pride, "These are my sons and daughters!"

Eight summers of hard work, Mendel discovered the basic laws of biological inheritance, and got the corresponding mathematical relationship formula. People called his discovery "Mendel's first law" and "Mendel's second rate", which revealed the basic laws of biological heredity.

When Mendel began his pea experiments, Darwin's theory of evolution had just been published. He studied Darwin's work carefully and absorbed a wealth of nutrients from it. Among Mendel's relics that have been preserved to this day, there are several copies of Darwin's writings, with Mendel's handwritten comments on them, which is a clear indication of the attention he paid to Darwin and his writings.

In the beginning, Mendel's pea experiment was not intended to explore the laws of heredity. His original intention was to obtain good varieties, only in the course of the experiment, gradually shifted the focus to explore the laws of heredity. In addition to peas, Mendel also made a large number of similar studies on other plants, including corn, violets and purple jasmine, etc., in order to prove that the laws of heredity that he discovered are applicable to most plants.

The difficulty of observing and discovering the laws of heredity in the overall form and behavior of organisms, but the ease with which they can be observed in individual traits, has long puzzled the scientific community. Mendel not only examined organisms as a whole, but also looked at their individual traits, which is one of the important differences between him and his predecessors as a biologist. Mendel's choice of experimental materials was also very scientific. Because peas are self-pollinating plants with stable varieties, they are easy to plant and easy to separate and count one by one, which provided favorable conditions for his discovery of the laws of heredity.

Mendel was aware of the epochal significance of his discovery, but he carefully repeated the experiment for many years, with a view to perfecting it even more. In 1865, Mendel read out the results of his research in two separate sessions in the conference hall of the Brunn Scientific Society. The first time, the attendees listened politely and excitedly to the report, Mendel only briefly introduced ? leaving the audience as if they had fallen into a cloud.

The second time, Mendel focused on the experimental data based on in-depth theoretical proof. However, the great Mendel thinking and experimentation is too far ahead. Although the vast majority of the participants were members of the Bruun Society of Natural Sciences, among them were chemists, geologists and biologists, as well as botanists and algae scientists specializing in biology. The audience, however, was not interested in the endless numbers and tedious proofs. They could not follow Mendel's thinking. Mendel with the heart and blood of the pea told him the secret, the current people can not be with the **** knowledge, has been buried for more than 35 years!

Mendel in his later years had confidently said to his close friend, Nijssel, professor of geodesy at the Higher Institute of Technology in Bruun, "Behold, my time has come." This statement became a great prophecy. The prophecy did not become reality until 16 years after Mendel's death, 34 years after the official publication of the pea experiment paper, and 43 years after he had engaged in the pea experiment. Mendel's experiments experimental map Mendel in 1856 to 1864 to choose the obvious differences between the 7 pairs of relative traits of pea varieties as parents, respectively, hybridization, and according to the genealogy of the hybrid progeny for a detailed record of the use of statistical methods, the calculation of hybrid progeny performance of the relative traits of the number of strains of plants and finally analyzed the proportion of their relationship. These seven pairs of traits are very stable, for example: red pea varieties, self-pollinated, its progeny only red flowers; round pea varieties of the progeny of the round seeds, they are:

1, seed shape - round and wrinkled grain;

2, cotyledon color - yellow and green;

3, flower color (seed coat color) - red and white (seed coat black-brown and white)

4, flower insertion position - leaf axils and tips;

5, immature pod color - green and yellow;

6, stem and vine (plant) height - tall and short;

7, pod shape - full and not full.

In Mendel's trials of the red-flowered × white-flowered hybrid combinations, the ratio of red flowers to white flowers was counted to be close to 3:1, and the same results were obtained in all the other pairs of crosses for relative traits. All the plants in the offspring generation showed the same traits, and all of them showed the traits of only one parent. And the trait of the other parent was hidden to be expressed. The traits that are expressed in this pair of relative traits are called dominant traits. Not shown, known as recessive traits; children in the second generation of plants in the performance of traits, part of the plants show a parental traits, the rest of the plants show another parental traits, that is, dominant traits and recessive traits have appeared at the same time, which is the phenomenon of segregation of traits. Mendel's Doctrine Mendel In 1866, Mendel published the results of his experiments in the Journal of the Brno Natural History Society, exposing the particles of biological inheritance and clarifying the laws of heredity, but his work was soon forgotten, and it was only in 1900 that he was reacquainted with his work. Mendel's work was soon forgotten and was only recognized in 1900. The main contents of Mendel's doctrine are:

1. The law of segregation:

Genes are transmitted from generation to generation as unique independent units. Cells have pairs of basic units of inheritance, and in the germ cells of a hybrid, the pairs of units come from the male parent and the female parent, and these units are separated from each other when the gametes are formed. In modern terminology, this means that the two genes (alleles) in the pair are located on two homologous chromosomes in pairs, and that during the production of sex cells by the parent organism, these alleles are separated, with one half of the sex cells having a certain form of the gene, and the other half having the other form of the gene. The offspring formed from these sex cells can reflect this ratio.

2, the law of independent distribution:

In a pair of chromosomes in the gene pair in the allele can be independently inherited, and other chromosomes in the gene pair in the allele; and contains a different pair of gene combinations of the sex cells can be randomly fused with another parent's sex cells. Mendel had already recognized that any germ cell equivalent to a sperm cell or an egg cell in the human body contains only one gene that is transmitted from one generation to the next by chance.

Mendel's two fundamental laws of heredity were the starting point of the new genetics, and Mendel has come to be known as the founder of modern genetics.

Mendel was known as the "strange man". In 1857, farmers in the southern suburbs of Brno, the second-largest city in the Czech Republic, discovered that a strange monk had arrived at the Brno monastery. This strange man, who had nothing better to do, reclaimed a field of peas behind the monastery, and spent his days using sticks, branches and ropes to prop up the pea seedlings spreading around, keeping them in an "upright position", and he even carefully chased away pollinating butterflies and beetles. He even carefully chased away pollinating butterflies and beetles. This strange man was Mendel. In the eyes of the other monks, Mendel's appearance was unforgettable: "Big head, a little fat, wearing a big bowler hat, shorts and boots, wobbling on the road, but with eyes that gazed at the world through gold-rimmed glasses." Born into a poor farming family, Mendel loved the natural sciences and had no interest in religion or theology. In order to escape a life of hunger and cold, he had to enter a monastery against his will and become a monk. At that time in Europe, people were keen to understand the mystery of biological heredity and mutation through plant hybridization experiments, and the study of heredity and mutation first need to choose the appropriate experimental materials, Mendel chose peas. 1857 summer, Mendel began to use 34 pea seeds to carry out his work, began a series of experiments that were known as "meaningless move", and lasted for 8 years. a series of experiments that lasted eight years.

Research results buried MendelThe evening of February 8, 1865, was a fine one, and Mendel, with the report of his experiments, which had been accumulated over a period of eight years, mounted the podium of the Higher Industrial School of Bruun, a small town in Austria (now Brno, Czechoslovakia), where an audience of more than 40 people, the majority of them members of the Bruun Society of Research in the Natural Sciences, came to hear him speak! -- a well-known chemist, geologist, and botanist and algalist specializing in biology. Almost no one understood what Mendel was really talking about in this lecture, and the logbook of the time reads, "There were no questions asked by anyone about Mendel's lecture, nor was there any discussion." They couldn't understand how biology and math could be connected, and they couldn't understand at all what the monk had wasted eight years of his life doing. Mendel titled his lecture "Experiments in the Hybridization of Plants". The following year Mendel's paper appeared, as was customary, in the Society's Journal of the Bruhn Society for the Study of Natural Science, and with it was sent to more than a hundred universities and libraries in Europe. But who pays attention to a locally organized journal? Mendel himself was aware of the importance of the discovery, and after receiving a single copy of the paper (*** forty copies), he distributed it to prominent botanists around the world in an attempt to draw the attention of the scientific community. But what botanist would pay any attention to the results of an amateur researcher? In desperation, Mendel wrote many letters to Karl von Nageli, the most famous botanist of his time, hoping to attract the attention of this great botanist. After a long time, he finally received a reply from Nageli. Nageli told Mendel, his experiment is still only a beginning, can not easily conclude. He suggested that Mendel repeat these experiments using camomile (Nagori's preferred research material) instead. After responding perfunctorily to this letter, Nagori put Mendel out of his misery. Almost twenty years later, he produced a major scholarly work on plant genetics that summarized all the experiments he knew about plant genetics, without a single word about Mendel.　　 Mendel also sent a copy of it to Darwin, and it was later discovered in Darwin's collection that the pamphlet had not even had its margins cut. Mendel, the founder of modern genetics Mendel was born in 1822, the year after Napoleon's death, to a poor peasant family in the then German-speaking region of Silesia, Austria. His childhood name was Johann Mendel, and he was the only boy in a family of five children. His hometown was known as the "Flower of the Danube", and everyone in the village loved gardening. A man named Schreiber conducted fruit tree training classes in his hometown, instructing the local residents in the cultivation and grafting of different plant varieties. He was impressed by Mendel's superior intellect. He persuaded Mendel's parents to send the boy to a better school to continue his studies, and in 1833 Mendel enrolled in a secondary school, and in 1840 in a philosophical college. In 1843, after graduating from college, at the age of 21, he entered a convent, not because he was called by God, but because he felt "compelled to take the first step in life which would relieve him of his arduous struggle for existence". Thus, for Mendel, "circumstances determined the choice of his profession."

In 1849 he was offered an opportunity to work as a high school teacher. But he scored miserably in the 1850 teachers' qualifying examination. In order to be "at least competent as a primary school teacher", his convent sent him to the University of Vienna under an educational decree in the hope that he would receive a full teaching diploma.

In this way, Mendel was permitted to study at the University of Vienna for four semesters, from 1851 to 1853. During this time, he studied physics, chemistry, zoology, entomology, botany, paleontology and mathematics. At the same time, he was influenced by distinguished scientists such as Doppler, for whom Mendel worked as an assistant in physics demonstrations; Ettinghausen, a mathematician and physicist; and Engel, an important figure in the development of the cell theory but who was attacked by the clergy for his denial of the stability of plant species. Mendel may have learned from him to view the cell as the structure of plant and animal organisms. Engel was the best biologist Mendel ever encountered. His view of heredity was concrete and practical: the laws of heredity were not determined by mental essence, nor by vital forces, but by real facts. Mendel was also greatly influenced by Engel in this respect.

In 1953, already 31 years old, Mendel returned to the monastery in Brno. At the same time there was an opportunity to teach at a recently created technical school in Brno. Around this time, Mendel decided to devote his life to specific experiments in biology.

In the summer of 1854 Mendel began his work with thirty-four strains of peas, and in 1855 continued to test their invariance in transmitting characteristic traits. 1856 saw the beginning of his famous series of experiments, the result of which for eight years was the paper read at the "Société d'Histoire Naturelle de Boulogne" in 1865. This paper was published in 1866 in the "Société d'Histoire Naturelle de Boulogne". This paper was published in the Proceedings of that Society in 1866. It was this paper, completely ignored at the time and later unearthed, that established Mendel's place in the history of genetics.

In 1868, Mendel was elected abbot of a monastery, and his stewardship deprived him of time and energy for scientific research. To Mendel's contemporaries, the cultured old monk seemed to be killing time in silly, but harmless, ways.On June 6, 1884, Mendel died of chronic kidney disease. His successors burned his private papers. As a result we have little direct knowledge of Mendel's source material or inspiration.

Now, let's turn to the eccentric research undertaken by this man who was seen as somewhat eccentric.

Mendel began with a collection of 34 pea lines that each had easily recognizable morphological characteristics. In order to ensure that the unique characteristics of these lines were stable (i.e., that the self-propagated offspring of each line had consistent characteristics), he grew these lines for two years, eventually selecting 22 purebred pea plant lines that were significantly different from each other. Mendel's pea field of different peas

After selecting the purebred peas, Mendel used them for crossbreeding, for example, crossing the tall ones with the shorter ones, crossing the round ones with the wrinkled ones, crossing the plants that produced white peas with the ones that produced grayish-brown peas, and crossing the plants that flowered along the pea vines from bottom to top with the ones that flowered at the top only. The purpose of his experiments was to use such crosses "to observe how each pair of traits varies, and to deduce the laws that control the emergence of these traits from generation to generation in the progeny of the cross."

Over the course of eight years, Mendel studied 28,000 plants, of which 12,835 were "carefully modified". Through these experiments, Mendel obtained a large amount of experimental data.

He found that if he crossed lines that had only one pair of traits, the first generation of hybrids (F1) would have only the traits of one parent. For example, crossing smooth round bean kernels with wrinkled rough bean kernels resulted in perfectly smooth round bean kernels. If the F1 generation is allowed to self-cross, then in the second generation of the resulting hybrid (F2) there are two situations: both smooth round bean grains and rough wrinkled bean grains. One of his experiments resulted in 5,474 smooth seeds and 1,850 rough seeds. The ratio of the two was about 2.96:1. This was the result of an experiment on just one trait of peas studied by Mendel. Mendel studied seven traits in one ****. The results of Mendel's experiments on the F2 generation are shown in the table below. It can be noticed that all the experiments had similar results. In the F1 generation only one trait will appear, while in the F2 generation both parents' traits will appear, and the ratio of traits that have appeared in the F1 generation to those that have not appeared in the F1 generation is close to 3:1.

Mendel's experiments didn't stop at the F2 generation, some experiments continued for five or six generations. But in all the experiments, the hybrids produced a 3:1 ratio. It was through these experiments that Mendel created the famous 3:1 ratio. But how to explain the results of such experiments?

Mendel introduced the Mendelian factor. He hypothesized that each trait in peas was controlled by a pair of factors. For example, for a purebred smooth round pea, it could be assumed to be determined by a pair of RR factors; for a purebred rough wrinkled pea, it was assumed to be determined by a pair of rr factors. For the hybrid generation, one factor is obtained from each of the parents, so that Rr is obtained. since the trait is only the appearance of round pea grains, this trait appearing in the F1 is called the dominant trait, while the trait not appearing in the F1 is called the recessive trait. Accordingly, the factor that determines the dominant trait is called the dominant factor, while the factor that determines the recessive trait is called the recessive factor. For the F1 generation with the Rr factor, self-crossing results in four outcomes: RR, Rr, Rr, rr, or simply RR + 2Rr + rr. Combining dominant and recessive, it is clear that the ratio of dominant traits to recessive traits is exactly 3:1. And "the offspring of the hybrid, segregation occurs from generation to generation in the ratio of 2 (heterozygous):1 (stable type):1 (stationary type)..."

Mendel's Pea Experiment - The Biology ShowThe results of the experiment were then perfectly explained under the assumption of the Mendelian factor.

The above is only an experiment with a single change factor. What if it is a multiple change factor? Mendel also did some experiments and research on this. He did two two-factor hybridization and one three-factor hybridization experiments. The results matched very well with his predictions based on the above theory. Various experiments proved that his theoretical assumptions were correct. He had solved the riddle of heredity and obtained the important laws of heredity. Mendel's discoveries have been summarized by later generations into two laws: (1) the law of segregation: genes do not merge, but are separated; if both parents are hybrids, the offspring are separated in the ratio of 3 dominant: 1 recessive; (2) the law of free combination: each pair of genes combines or separates freely without being affected by other genes. Mendel's outstanding research results are reflected in his 1865 paper and the 1866 Proceedings of the Bloom Conference. The proceedings were sent to about 120 libraries, and 40 copies of the paper were distributed to other botanists. However, apart from a few mentions by the German botanist Falk and others, it can be said that Mendel's extraordinary work had little repercussions at the time, and Mendel's findings were completely ignored. As an interlude, Darwin allowed Falk's article, which mentioned Mendel's work, to slip under the radar: Darwin had read the table of contents of Falk's article, but did not bother to pay attention to the main text. What would have been the result if Darwin had taken a serious look at the main text? We have no intention of engaging in more historical reverie.

This great paper was discovered independently by three botanists at the beginning of the twentieth century, after more than 30 years of neglect. As a result, the obscure pioneer was reevaluated, and his paper was recognized as having opened up modern genetics. In 1965, in a speech celebrating the 100th anniversary of the publication of Mendel's paper mentioned above, a British expert on evolution said, "This is the only instance in which a science has been born wholly in the mind of a single man! ". In another speech in the same year, he stated even more explicitly: "It is a rarity to state exactly when and where a branch of science was born, with the exception of heredity, which owes its birth to one man: Mendel. It was he who, on February 8 and March 8, 1865, at Brno, enunciated the fundamental laws of heredity." Dying in 1868, Mendel was elected abbot of the monastery, and from then on he gradually shifted his energies to monastic work, eventually giving up scientific research altogether. He was only forty-six years old in that year, and seemed too young to be an abbot. In those days, when an abbot died, the government would send someone to check the accounts and impose heavy taxes. It was for this reason that monasteries tended to elect younger monks as abbots, and in 1874 the Austrian government enacted a harsh tax code. Mendel refused to pay the taxes, believing the new law to be unfair, and spent large sums of money on a protracted lawsuit against the government. The abbots of other monasteries were bribed by the government and gave in, but only Mendel resisted the government's threats and inducements and was determined to resist to the end. The result was predictable. The court ruled against Mendel, and the monastery's funds were confiscated. The monks of the monastery also turned their backs on Mendel and surrendered to the government. Mendel's mind and body collapsed and he suffered a serious heart attack. On January 6, 1884, he "seemed to be in good spirits," and the nurse greeted him with the words, "You are looking well." Five minutes later, the nun who had gone to visit Mendel found him leaning on a couch, having stopped breathing.

Results recognizedMendel's full-body imageSeventeen years later, in 1900, Dutch biologist De Vries discovered the laws of genetics through experiments similar to Mendel's. He went to the library to check the literature and found that as early as 35 years ago, Mendel's "Experiments in Plant Hybridization" had already argued the laws of plant heredity. At the same time, the German biologist Kollens and the Austrian biologist Cermak also coincidentally discovered this. All three well-known European biologists mentioned Mendel's doctrine in their respective published papers and declared that they had only confirmed Mendel's view. Mendel's name immediately spread throughout Europe, and people clamored to test Mendel's laws of genetics by planting peas in their own experimental fields. 1965, in a speech celebrating the 100th anniversary of Mendel's papers, a British evolutionist said, "Genetics owes its birth to a single man--Mendel. -Mendel, who on February 8, 1865, in Brno, enunciated the fundamental laws of heredity. This is the only example of a science born entirely in the mind of one man." In his later years, Mendel once told his friend G. Nelson, "Wait and see, my time will come someday." With the first crow of the rooster in the 20th century, three scholars from three countries simultaneously and independently "rediscovered" Mendel's laws of heredity, and 1900 became an epochal year in the history of genetics and even in the history of biological sciences. From then on, genetics entered the Mendelian era. Personal Influence Mendel With scientists deciphering the genetic code, people have a deeper understanding of the genetic mechanism. Now, people have begun to move toward controlling the genetic mechanism, combating genetic diseases, synthesizing life, and other greater work for the benefit of mankind. Yet all of this is linked to the name of the monk at St. Thomas Abbey who dedicated himself to science.

Today, through the work of generations of scientists such as Morgan, Avery, Hirsch, and Watson, it has been made possible to base the mechanism of biogenetic inheritance - the question that haunted Mendel - on the genetic material DNA.