Mendel, the pioneer of Mendel genetics, chose pea as the "protagonist" in the experiment of genetic factors. And found genetic factors from peas, becoming a pioneer in genetics.

182 1 On July 22nd, Mendel was born in Heisendo, Czech Republic (then belonging to Austria). He is the only boy among five children in the family. When the farmer's father thinks farming is too hard, he hopes Mendel can read more books and find a better job in the future.

On the other hand, Mendel did live up to expectations. He has shown outstanding qualifications since he was a child and has always been among the best in school work. When Mendel was in middle school, the headmaster also noticed that he was a talented person, and if he stayed in this small middle school in his hometown, he would be buried, so he persuaded his parents to transfer him to a bigger school-Lepinik Middle School.

After graduating from pre-university high school, he re-entered the pre-university school with excellent results. Mendel's tuition and fees for school have always been saved under the condition of patchwork at home. By the time I went to college, the huge tuition and miscellaneous fees had exhausted the last strength of my family, and I was unable to pay for meals. My parents take turns to walk more than 30 kilometers every day to deliver bread to Mendel. Under this pressure, Mendel still tried his best to study hard, but hard life and overwork still dragged down his health.

For an excellent scientist, it is really great happiness to see his inventions or discoveries recognized by people all over the world and even awarded medals, such as Roentgen, Watt, Edison, Madame Curie and others. However, there is another kind of scientist, whose research before his death found that he was not understood by the world. It was not until many years after his death that his theory was taken seriously and then affirmed by the world. This kind of scientist has been alone on the road of discovering truth all his life. Our "father of genetics" Mendel is such a scientist.

Farmer's children

Mendel is an Austrian, born in 1822. His father took part in several battles against Napoleon. He is a well-informed man. After the war, he returned to his hometown to farm and run an orchard. Mendel often goes to the garden to help his father with his work. Orchard is the best natural school for teenagers. Perhaps it is this environment that gave birth to Mendel's motivation to explore genetic laws by cultivating plants in the future. Although Mendel's father was only a farmer, he had extraordinary foresight. He knew that if farmers want to get rid of the oppression of landlords and autocratic governments, they must learn and ask questions to gain a higher position, so he tried his best to train Mendel to receive higher education.

However, Mendel's academic career was not very smooth, mainly because of the poor economic situation at home. Mendel had to go on a diet when he left home to study, which led to malnutrition and illness. In severe cases, he even had to drop out of school and rest at home. Despite this, Mendel finally entered a short-term university-Olmertz College with his perseverance and the support of his sister's dowry. Later in 1843, Mendel accepted the recommendation of a professor and entered a monastery of St. Augustine's school as a trainee priest to learn knowledge. After graduating from the monastery, he should have been a full-time priest, but after serving for one year, Mendel felt that he was more suitable for learning and teaching, so he asked to be a substitute teacher in a middle school.

A substitute teacher is better.

During his tenure as a substitute teacher, Mendel was very popular with students because of his earnest teaching. So the school asked him to take the formal teacher qualification examination. I didn't expect Mendel to fail in biology and geology. Nevertheless, Mendel's monastery sent him to Vienna University for further study. At the University of Vienna, Mendel studied various natural subjects and mathematics, and got the guidance of many excellent professors, which laid his research ability.

After finishing his studies in Vienna, Mendel returned to teach at a college in Brno, where the monastery is located. Mendel and all kinds of experts and professors in the school get along day and night, and the time is14 (1854-1868). These fourteen years of teaching career have become the most important golden years in Mendel's life; The famous Mendel's law of heredity was also developed at this time. From the data, it seems that Mendel did not get a formal teacher qualification in his life, but his academic support and teaching ability will never be lost to a university professor. Therefore, diplomas and academic qualifications do not mean everything, but their own abilities and strengths are more important.

Pea experiment in open space

During 14 years, Mendel lived in schools and monasteries. He is a good teacher at school; He is a researcher at the monastery. In the backyard of the monastery, next to the window, there is a clearing 35 meters long and 7 meters wide.

Naturally, Mendel confirmed the scientific truth in this liquidation and explained people's long-term doubts. At that time, although people had found some similarities between the previous generation and the next generation, they always thought, "That's the way it is! There is nothing strange ",and the scientific community has not conducted in-depth research and discussion.

Mendel found peas in the open space, some with white flowers and some with yellow flowers; There are tall stems and short stems; Some pods are round, others are dry and flat. Mendel used long-term observation and comparison to see the similarities and differences between the next generation of peas. During the pea harvest, he made a systematic statistics on the harvest results, and the number of recorded plants exceeded 2 1000. After long-term observation and a large number of statistical data, Mendel found that if long-stemmed peas mate with short-stemmed peas, offspring and grandchildren will be long-stemmed, until the fourth generation, only one of the four plants is short-stemmed. Mendel further experimented with animals: white mice and black mice.

The clearing where Mendel once experimented with peas is behind the monastery.

Mice mate, and the second generation is all black mice; Let the second generation of black mice mate with each other, and a quarter of the third generation will be white mice. Mendel gradually sorted out some clues about the relationship between parents and offspring through animal and plant experiments.

mendel's genetic law

After nearly nine years of hard work, his efforts finally paid off. 1865, he published his research results in the local natural history society in Brno, and his thesis was entitled "Plant hybridization experiment". 1869 published his second paper "Research on Animal and Plant Genetics", which is the crystallization of his lifelong research on genetics. Unfortunately, these two papers did not attract the attention of the world, because people at that time did not know what practical value genetics had, let alone what impact it had on human beings.

Mendel's theory, the little jar teacher simply sorted him into the following points:

First, there is a basic unit (now called gene) in biological tissue, through which parents' characteristics can be passed on to the next generation.

Second, every individual characteristic, such as the color or height of peas, is determined by a pair of genes, which are composed of a pair of genes inherited from the previous generation.

3. If the genes inherited by future generations have different characters, such as one gene will show the characteristics of high stem and the other gene will show the characteristics of low stem, then only the characteristics of strong stem will be shown (we call it dominance). Take peas as an example, high stem will appear. This phenomenon is called "the law of superiority". But the recessive gene will not disappear or be destroyed, it will be passed on to the next generation through natural probability distribution.

Parents' genes are distributed and then passed on to their offspring. Which gene is paired with which gene is completely random and accidental.

5. Heredity is closely related to sex cells, and features that do not belong to sex cells cannot be inherited. Therefore, diseases caused by acquired environment and work will not be inherited, and diseases caused by bacterial infections will not be inherited; But some mental disorders and neurasthenia are hereditary.

Belated applause

1868, Mendel was appointed as the director of the local monastery. Since then, due to the busy administrative affairs, he was unable to continue his genetic research. In addition, the monasteries at that time were often unhappy with the government because of tax issues, which made Mendel entangled in these heavy tasks and eventually died of illness in 1884. After more than 30 years of silence in the cemetery, Mendel suddenly became famous. The reason is that in 1900, scientists from Holland, Germany and Austria experimented with different plants and got the same results as Mendel. At this time, his research has been valued and affirmed by the scientific community.

Since then, more scientists have repeated Mendel's genetic experiments and further discovered genes through chromosome research, and then expanded from gene research to cytology, embryology, eugenics, biochemical technology, and even the most popular technologies such as "cloning sheep" and "cloning human beings".

Mendel walked in the forefront of the times, leaving him alone to die; However, the beauty of studying science is that as long as it is "truth", there will be applause one day, but you don't know when. Copernicus, Galileo and Mendel are all such people!