Which country does biologist Mendel come from?

Gregor Mendel (1822-1884),1822, was born in a peasant family near Silesia, Austria. He likes gardening since he was a child. Due to family difficulties, he didn't finish college and became an academician in a temple in Bulong. 1847 obtained the position of pastor. With the support of friends, 1850 went to the School of Science of Vienna University for further study. /kloc-in the summer of 0/853, I returned to Bulong Temple and worked as a teacher of zoology and botany in Times School. Combining with teaching, he engaged in hybridization experiments of plants and finally discovered the genetic law. He published his research results in Brno Natural Science Association in 1865, but it was buried until the beginning of the 20th century, thus confirming Mendel's position in genetics. Basic information name: Mendel

Birth and death:1July 22, 822

Constellation: Cancer

Place of birth: Austria

Description: Mendel is the father of modern genetics and the founder of this important biological subject. 1865 found the genetic certainty rate. Childhood experience Mendel Mendel's father loves gardening and is an expert in fruit tree cultivation and grafting. Farmers nearby often ask him for advice. John learned to do all kinds of farm work under the influence of his father since childhood and became interested in fruit tree grafting. Once he asked his father, "Dad, why can a small good scion grow into a rough branch and sweet fruit, even though all the nutrition is provided by poor rootstocks?" "Son, I don't know why! But it's true. What is more powerful than nutrients is the nature of trees, which is what people call the' genetic' nature! " Father answered John's question according to his knowledge. Little Mendel listened quietly, lost in thought: "Nature of Trees" and "Inheritance", what are those? He kept muttering to himself. The grafting experience in childhood and the biological activities organized in primary school laid a deep foundation in Mendel's young mind, which greatly influenced him to become a world-famous great biologist who discovered the genetic law. Career Mendel Mendel was born in Silesia, Austria-Hungary, into a poor fruit farmer's family. He used to take care of fruit trees at home and help raise bees at school, so he has accumulated a lot of experience in this field. In order to help him finish high school, his sister gave up his inheritance. Since then, Mendel entered a monastery in order to study science without involving his parents and sisters, and also to get a good education, which also gave him the opportunity to systematically study modern natural science at Vienna University. All these laid a solid foundation for his later discoveries. After graduating from college, Mendel taught in a middle school run by a local church, teaching natural science. He can concentrate on preparing lessons and teaching seriously, which is very popular with students. 1843, 2 1 year-old Mendel entered the monastery, worked as a science teacher in a nearby high school, and then went to Vienna University for further study. He received a fairly systematic and strict scientific education and training, which laid a solid foundation for later scientific practice. After long-term thinking, Mendel realized that it is more important to understand the mechanism that keeps genetic traits unchanged from generation to generation.

Shortly after Mendel returned to Bruen from Vienna University, he began his pea experiment for eight years. Mendel first got 34 varieties of peas from many seed vendors, and selected 22 varieties for experiments. They all have some stable characters, which can be distinguished from each other, such as tall or short stems, round or wrinkled materials, and gray or white seed coats.

Mendel carefully observed, counted and analyzed the characters and quantity of peas in different generations by artificially cultivating these peas. Using this experimental method requires great patience and rigorous attitude. He loves his research work, and the guests who often visit him point to Doudou and say proudly, "This is my child!" " "

After eight years of hard work, Mendel discovered the basic laws of biological inheritance and obtained the corresponding mathematical relationship. People call his discovery "Mendel's first law" and "Mendel's second rate" respectively, which reveals the basic law of biological genetic mystery.

When Mendel started experimenting with peas, Darwin's theory of evolution had just come out. He studied Darwin's works carefully and absorbed rich nutrition from them. Among Mendel's relics preserved to this day, there are several Darwin's works with Mendel's handwriting on them, which shows his concern for Darwin and his works.

At first, Mendel's pea experiment was not to explore genetic laws. His original intention was to obtain excellent varieties, but during the experiment, he gradually shifted his focus to exploring genetic laws. In addition to peas, Mendel has done a lot of similar research on other plants, including corn, violets and mirabilis jalapa, to prove that the genetic laws he discovered are applicable to most plants.

It is difficult to observe and discover the genetic law from the overall form and behavior of organisms, but it is easy to observe from individual traits, which is also the reason for the long-term confusion in the scientific community. Mendel not only inspects the whole organism, but also pays attention to its individual characters, which is one of the important differences between him and his predecessors. Mendel's experimental materials are also very scientific. Because pea is a self-pollinating plant, its variety is stable, easy to plant and separate, and it is counted one by one, which provides favorable conditions for him to discover the genetic law.

Mendel knew that his discovery was of epoch-making significance, but in order to improve it, he carefully repeated the experiment for many years. 1865, Mendel read out his research results twice in the conference hall of Bruen Science Association. For the first time, the participants listened to the report politely and happily, and Mendel just gave a brief introduction? Make the audience confused.

The second time, Mendel made an in-depth theoretical proof based on experimental data. However, the great Mendel's thoughts and experiments are too advanced. Although most of the participants are members of Bruen Natural Science Association, there are chemists, geologists and biologists, as well as botanists and algae experts in biology. However, the audience is not interested in endless numbers and complicated and boring theories. They really can't follow Mendel's thinking. Mendel's secret, told by painstakingly watered peas, has been buried for 35 years.

In his later years, Mendel confidently said to his good friend Geser, a professor of geodesy at Bruen Institute of Advanced Technology, "Look, my time has come." This sentence became a great prophecy. It was not until Mendel's death 16, 34 years after the pea experiment paper was officially published, and 43 years after the pea experiment, the prediction became a reality. Mendel's experimental chart ranged from 1856 to 1864. Mendel chose seven pairs of pea varieties with obvious differences as parents, crossed them respectively, and recorded them in detail according to the pedigree of the hybrid offspring. The number of plants with related traits in hybrid offspring was calculated by statistical method, and the proportional relationship between them was analyzed. These seven pairs of traits are very stable, such as: pea varieties with red flowers only bloom red flowers after self-pollination; The offspring of pea varieties bear many round seeds. They are:

1, seed shape-round and wrinkled;

2. Cotyledon color-yellow and green;

3. Color (seed coat color)-red and white (seed coat is dark brown and white);

4. The position of flowers-axils and tips;

5. Immature pod colors-green and yellow;

6. The height of stems and vines (plants)-high and short;

7, pod-like-full and not full.

In Mendel's cross experiment of safflower× white flower, the ratio of safflower to white flower was close to 3∶ 1, and the same test results were obtained in other related traits. In the first generation, all the plants have the same characters, and only one parent is shown. And the characteristics of the other parent are hidden and displayed. This pair of relative traits is called dominant traits. What is not shown is called recessive trait; In the second generation, some plants show the traits of one parent, and some show the relative traits of another parent, that is, dominant traits and recessive traits appear at the same time, which is the phenomenon of trait separation. Mendel theory Mendel 1866, Mendel published his experimental results in the journal of the natural history society of Brno and the journal of the natural history society, which revealed the granularity of biological inheritance and expounded its genetic law, but his work was soon forgotten by people until 1900. The main contents of Mendel's theory are:

1, separation phenomenon:

Genes are passed down from generation to generation as unique independent units. Paired basic genetic units in cells. In hybrid germ cells, pairs of genetic units come from male and female parents, and these genetic units are separated from each other during gamete formation. According to modern terminology, that is to say, two genes (alleles) in a gene pair are located on two homologous chromosomes in pairs, and the alleles are separated in the process of the mother organism producing sexual cells, half of which have one form of genes and the other half have another form of genes. The offspring formed by these sexual cells can reflect this ratio.

2, independent distribution method:

Alleles in a pair of chromosomes can be inherited independently and have nothing to do with alleles in other chromosome pairs; And sex cells with different gene combinations can be randomly fused with sex cells of another parent. Mendel already knew that any germ cell equivalent to sperm cell or egg cell in human body contains only one gene passed down from generation to generation by chance.

Mendel's two basic laws of heredity are the starting point of new genetics, so Mendel is called the founder of modern genetics by later generations.

Mendel 1857, known as the "freak", farmers in the southern suburbs of Brno, the second largest city in Czech Republic, found a strange monk in Brno monastery. This "go looking for trouble" weirdo dug a pea field behind the monastery, and propped up the spreading pea seedlings with sticks, branches and ropes all day to keep them in an upright position. He even carefully drove away butterflies and beetles that spread pollen. This weirdo is Mendel. In the eyes of other monks, Mendel's appearance is unforgettable: "He has a big head, a little fat, wears a hat, shorts and boots, and walks unsteadily, but he has a pair of eyes staring at the world through gold-rimmed glasses." Mendel was born in a poor peasant family. He likes natural science very much and is not interested in religion or theology. In order to get rid of hunger and cold, he had to enter the monastery against his will and become a monk. In Europe at that time, people were keen to understand the mystery of biological heredity and variation through plant hybridization experiments, and the first thing to study heredity and variation was to choose appropriate experimental materials. Mendel chose peas. /kloc-in the summer of 0/857, Mendel started his work with 34 pea seeds and started a series of experiments called "meaningless actions", which lasted for 8 years.

The research results were buried by Mendel. 1865 On the evening of February 8th, the weather was fine. With the experimental report accumulated in eight years, Mendel boarded the platform of the Austrian Higher Technical School in Bruen (now Brno, Czech Republic). More than 40 listeners came to listen to his speech, most of whom were members of Bruen Natural Science Research Association-famous chemists, geologists, botanists and algae scientists, majoring in biology. In this speech, almost no one understood what Mendel said. At that time, the diary recorded: "No one asked questions, and no one discussed Mendel's speech." They can't understand how biology and mathematics are linked, and they can't understand what this monk has been doing for eight years. Mendel named his speech "Plant Hybridization Experiment". In the second year, Mendel's paper was published in the Journal of Bruen Natural Science Research Society as usual, and was sent to more than 0 universities and libraries in Europe 100 with the journal. But who will pay attention to the journals of a local organization? Mendel himself knew the importance of this discovery. After he received the monograph (* * * 40), he distributed it to famous botanists all over the world, trying to attract the attention of the scientific community. But which botanist will pay attention to the results of an amateur researcher? In desperation, Mendel wrote many letters to KarlvonNageli, the most famous botanist at that time, hoping to attract the attention of this great botanist. After a long time, he finally received a reply from Named. Nagori told Mendel that his experiment was just the beginning and he could not draw a conclusion easily. He suggested that Mendel repeat these experiments with chamomile (Nagri's favorite research material). After a perfunctory reply to this letter, Nagory forgot Mendel. Almost twenty years later, he published a large-scale academic book on plant genetics, summarizing all the experiments he knew about plant genetics, but said nothing about Mendel. Mendel also sent a copy to Darwin, and later found in Darwin's library that the booklet had not even been cut. Mendel 1822, the founder of modern genetics, was born in a poor peasant family in German Silesia, Austria, the year after Napoleon's death. His childhood name was John Mendel, and he was the only boy among five children. His hometown is known as the "Flower of the Danube", and everyone in the village loves gardening. A man named Schreiber once started a fruit tree training class in his hometown to guide local residents to cultivate and graft different plant varieties. He was deeply impressed by Mendel's extraordinary intelligence. He persuaded Mendel's parents to send the boy to a better school to continue his studies. 1833, Mendel entered a middle school. 1840, he was admitted to a philosophy school. In college, he was almost penniless, and he had to go to school frequently. 1843, after graduating from college, 2 1 entered the monastery, not because he was inspired by God, but because he felt "forced to take the first stop in life, so as to free himself from the pain of struggling for survival". Therefore, for Mendel, "the environment determines his career choice".

1849 He got a chance to be a middle school teacher. However, in the 1850 teacher qualification examination, his performance was terrible. In order to "at least be competent as a primary school teacher", his monastery sent him to Vienna University according to an education order, hoping that he could get a formal teacher diploma.

In this way, Mendel was allowed to study in Vienna University, and spent four semesters from 185 1 to 1853. During this period, he studied physics, chemistry, zoology, entomology, botany, paleontology and mathematics. At the same time, he was also influenced by outstanding scientists, such as Doppler and Mendel as his physics demonstration assistants; Another example is Howard Johnson Yi Ting, a mathematician and physicist. There is Engel, who is an important figure in the development of cell theory, but was attacked by the priest for denying the stability of plant species. Mendel may have learned from him that cells are regarded as the structure of animal and plant organisms. Engel is the best biologist Mendel has ever seen. His view on heredity is concrete and practical: the law of heredity is not determined by spiritual essence, nor by vitality, but by real facts. Mendel was also deeply influenced by Engels in this respect.

1953, 3 1 year-old Mendel returned to the monastery in Brno. At the same time, I have the opportunity to teach in a newly established technical school in Brno. It was about this time that Mendel decided to devote his life to specific experiments in biology.

/kloc-in the summer of 0/854, Mendel started his work with thirty-four pea strains. 1855, and continue to test their invariance when transmitting characteristic traits. 1856, he started a series of famous experiments, and the result of eight years' experiments was 1865, a paper he read in the Bloom Society of Natural History. This paper was published in 1866. It was this paper that was completely ignored at that time and was excavated in the future, which laid the position in Mendel's genetic history.

1868, Mendel was elected as the abbot, and the management deprived him of time and energy for scientific research. To Mendel's contemporaries, this educated old monk seems to be killing time in some stupid but harmless ways. 1On June 6th, 884, Mendel died of chronic kidney disease. His successor burned his personal documents. So we have little direct knowledge of Mendel's original materials or inspiration.

Now, let's turn to the eccentric research conducted by this man who is considered a little eccentric.

Mendel first collected 34 pea strains with easily recognizable morphological characteristics. In order to ensure the stability of the unique traits of these strains (that is, the offspring of each strain have the same traits), he planted these strains for two years and finally selected 22 purebred pea strains with obvious differences. Mendel's pea field, different peas.

After Mendel selected purebred peas, he used them to cross, such as crossing tall and short, crossing round and wrinkled, crossing white peas with grayish brown peas, and crossing plants that bloom from bottom to top along pea vines with plants that only bloom at the top. The purpose of his experiment is to "observe the changes of each pair of traits through this hybridization, and deduce the laws that control the appearance of these traits in the offspring of hybridization."

In eight years, Mendel studied 28,000 plants, of which12,835 plants were "carefully transformed". Through these experiments, Mendel obtained a lot of experimental data.

He found that the first generation hybrid (F 1) only showed the traits of one parent if only one pair of lines crossed. For example, a smooth round bean crosses a wrinkled rough bean, and the result is a completely smooth round bean. If F 1 selfs, there will be two situations in the second generation (F2): smooth round beans and rough wrinkled beans. One of his experimental results is: 5474 smooth seeds and 0/850 rough seeds. The ratio of the two is about 2.96: 1. This is only the experimental result of Mendel's study on a character of pea. Mendel studied seven personalities. Mendel's experimental results about F2 generation are as follows: It can be found that all experiments have similar results. F 1 generation has only one trait, but both parents will appear in F2 generation, and the ratio of traits that have appeared in F 1 generation to those that have not appeared in F 1 generation is close to 3: 1.

Mendel's experiments did not stop at F2 generation, and some experiments lasted for five or six generations. However, in all experiments, the ratio of hybrid production was 3: 1. It was through these experiments that Mendel founded the famous ratio of 3: 1. But how to explain such experimental results?

Mendel introduced the Mendel factor. He thinks that every character of pea is controlled by a pair of factors. For example, for pure smooth peas, it can be assumed that it is determined by a pair of RR factors; For purebred rough-wrinkled peas, the hypothesis is determined by a pair of rr factors. For the hybrid generation, one factor is obtained from each parent, so Rr is obtained. Because only round beans appear in this trait, the trait that appears in F 1 is called dominant trait, and the trait that does not appear in F 1 is called recessive trait. Accordingly, the factors that determine dominant traits are called dominant factors, and the factors that determine recessive traits are called recessive factors. For F 1 generation with Rr factor, self-intersection has four results: Rr, Rr, RR. Or simply: RR+2RR+RR. Combining dominance and recessive traits, it is obvious that the ratio of dominant traits to recessive traits is 3: 1. And "the offspring of hybrids are separated from generation to generation, and the ratio is 2 (miscellaneous): 1 (stable foot type): 1 (stable foot type) ..."

Mendel pea experiment-biological display. Therefore, under the assumption of Mendel factor, the experimental results are perfectly explained.

The above is only an experiment of univariate factors. What if it's a multivariate factor? Mendel has also done some experiments and research on this. He did two two-variable factor hybridization experiments and one three-variable factor hybridization experiment. The result is very consistent with his prediction based on the above theory. Various experiments have proved that his theoretical hypothesis is correct. He solved the mystery of heredity and obtained important genetic laws. Mendel's discovery is summarized into two laws: (1) separation phenomenon: genes are not fused, but separated from each other; If both parents are hybrids, the offspring are separated according to the ratio of 3 dominance: 1 recessive; (2) Law of free combination: each pair of genes can be combined or separated freely, and is not affected by other genes. Mendel's outstanding research achievements are reflected in his 1865 papers and 1866 Bloom conference proceedings. The minutes of this meeting have been sent to about 120 libraries, and 40 papers have also been sent to other botanists. However, Mendel's extraordinary work was mentioned by German botanist Fokker and others. It can be said that there was almost no response at that time, and Mendel's research results were completely ignored. As an episode, Darwin let Fogg's articles referring to Mendel's work slide under his eyes: Darwin read the catalogue of Fogg's articles, but he didn't pay attention to the text. What if Darwin could read the text carefully? We have no intention of making more historical reverie.

After being ignored for more than 30 years, this great paper was independently discovered by three botanists at the beginning of the twentieth century. As a result, this unknown pioneer was re-evaluated and his paper was recognized as opening up modern genetics. 1965, an English evolutionist said in a speech celebrating the 0/00th anniversary of Mendel's publication of the above paper105 that "a science was born completely in one's mind, which is the only example". In another speech in the same year, he pointed out more clearly: "It is unusual to say exactly when and where a branch of science was born. Genetics is an exception, and its birth is attributed to one person: Mendel. It was he who expounded the basic laws of genetics in Brno on February 8 and March 8 of 1865. " 1868 After his death, Mendel was elected as the abbot. After that, he gradually shifted his energy to the monastery work, and finally gave up scientific research completely. He is only forty-six years old this year, and he is too young to be an abbot. At that time, after the abbot died, the government would send someone to audit the accounts and levy heavy taxes. It is for this reason that monasteries tend to elect young monks as deans. 1874, the Austrian government promulgated a strict tax law. Mendel thought the new tax law was unfair, refused to pay taxes, and spent a lot of money to fight a protracted lawsuit with the government. The directors of other monasteries were bought by the government and gave in. Only Mendel resolutely rejected the threats and inducements of the government and was determined to resist to the end. The result can be imagined. The court ruled that Mendel lost the case and the monastery's funds were confiscated. Monks in the monastery also turned their backs on Mendel and compromised with the government. Mendel's body and mind completely collapsed, and he had a serious heart attack. 1October 6, 1884, his spirit looks "good", and the nurse greets him: "You look really good." Five minutes later, the nun who visited Mendel found that he had stopped breathing by leaning on the sofa.

This achievement is recognized as Mendel's full-length portrait. 17 and 1900 years later, Dutch biologist Defrees discovered the laws of genetics through experiments similar to Mendel's. He went to the library to consult the literature and found that as early as 35 years ago, Mendel's plant hybridization experiment had demonstrated the genetic law of plants. At the same time, German biologist Collins and Austrian biologist Cermak also discovered this point. Three famous European biologists all mentioned Mendel's theory in their published papers, and claimed that they only confirmed Mendel's point of view. Mendel's name immediately spread all over Europe, and people rushed to plant peas in their own experimental fields to test Mendel's genetic law. 1965, an English evolutionist said in a speech celebrating the anniversary of the publication of Mendel's paper 100: "The birth of genetics is attributed to a person-Mendel, who expounded the basic laws of genetics in Brno on February 8, 1965. A science was born completely in a person's mind, which is the only example. " In his later years, Mendel once said to his friend G Nelson, "Wait and see, my time will come one day." With the cock crowing for the first time in the 20th century, three scholars from three countries independently "rediscovered" Mendel's genetic law. 1900 is an epoch-making year in the history of genetics and even in the history of biological sciences. Since then, genetics has entered the Mendel era. Personal influence Mendel With scientists deciphering the genetic code, people have a deeper understanding of the genetic mechanism. Now, people have begun to control the genetic mechanism, prevent genetic diseases and synthesize life, which will be more beneficial to human beings. However, all this is related to the name of the monk who devoted himself to science in St. Thomas Cathedral.

Today, after the research of several generations of scientists such as Morgan, Avery, hershey and Watson, the problem of biological genetic mechanism that puzzles Mendel has been based on the genetic material DNA.