Biology. Basic questions. Gene (۲)

How is any trait passed from parents to children? After all, why are parents and children the same? The idea that has been popular for a long time is that there is a small man inside the sperm. Completely made in a small package and it becomes human. This little man is homeless. And within this little man there are people of the next generation, and so on. It was all placed with the first man. This is how all human beings came to earth at the beginning of the human race. Closed inside one next humancoles. This theory became so popular that it did not disappear after the invention of the microscope. In 1699, a Dutch microscopist claimed to have seen many small humans in human sperm. (It was the same imagination that shows faces on clouds). In the seventeenth century, sperm was depicted as a scalp with long hair on the back. This was the idea of ​​pre-formationism. Transfer code is not the whole person.

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Not everyone agreed with the pre-formation. It did not explain at all what happens when the sperm meets the egg. The answer was given in 1768 by the Berber embryologist Caspar Wolf. His idea, similar to that of Aristotle, was that there was information in the embryo. There are no instructions.

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When biologists, philosophers, religious scholars and embryologists were having heated debates in the eighteenth and nineteenth centuries, the fact was that no one could go further than Aristotle and Pythagoras to answer this question.

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The mid-nineteenth century was a time when biology was a static theory. As a physicist describes the movement of a ball in the air, why not in biology? Why isn't biology like a continuum, a process, a progression, a history? There were two people asking this question. Both were gardeners, both obsessed with nature, both from theology to biology, and both wanted to understand the basics of biology. Mendel's question was microscopic. How information is passed from one generation to the next. Darwin's question was microscopic. How much does information change in a thousand species of living things? The ideas presented by both of them answered different things. But over time, their visions became closer and closer, giving rise to the most important combination of modern biology. This combination formed the basis of modern biology. This theory of hereditary understanding is called modern synthesis.

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Darwin sailed on the Beagle on December 27, 1831. Arrived in the Galapagos Islands on October 20, 1835. He developed theories from the observations of birds and animals in this cluster of islands. Another trip was made by Wallace, who was from Brazil. Both were reaching the most important theory of biology. Darwin and Wallace's papers on evolution by natural selection were read at the Lenin Society in London on July 1, 1858. How important was that? No one immediately realized this. Even the president of the Lenin Society commented at the end of the year, "1858 has been a barren year in terms of new discoveries in biology. No specific discoveries were made. " The following year, on a cold Thursday morning, November 24, 1859, Darwin's book, The Origin of Species, was published. It was priced at fifteen shillings. Two and a half hundred copies of the first edition were sold on the first day.

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Darwin's breakthrough was significant but incomplete. The biggest gap was that there was no theory of inheritance. After all, how does any trait pass from one generation to the next?

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Darwin, after years of careful observation and years of thought, had proposed the theory of evolution, but the absence of inheritance in it bothered Darwin the most. Inheritance theory that gives stability and room for change. Darwin's idea was that there were gametes in the body that kept collecting information about the state of the body and then they were found in the initial crime cells of the father and mother just like in a color box. Colors match Darwin's idea was a combination of the ideas of Aristotle and Pythagoras, and was written in 1867, ten years after his book Origin of Species, in his book, Diversity in Animals and Plants.

Criticism of Darwin's book and the theory of pan-genes came unexpectedly from Fleming Jenkins, a mathematician and engineer. He had read the book in detail and found a blatant error in it. Jenkins went on to argue, "Suppose a white man arrives on an island inhabited by blacks. We also assume that he is made king and he gets married many times and has children, but still his children have half of these characteristics. A quarter of grandchildren. Beyond this, the eighth part, and thus in a few generations, his "whiteness" will disappear, even if this feature is not so useful and fit as to make him king and help him to pass on his features. " The gist of Jenkins' story was that even if diversity did come, it would soon become average. How will it survive after diversity?

Darwin was shaken by Jenkins' logic. "Criticism of Fleming has been more useful to me than any other article," he wrote. What did that mean? Inheritance could not be the same as color matching for evolution to work. The "atoms" of information were needed. Indivisible packets that can be passed from parent to child.

Was there evidence of such a method? If Darwin had thoroughly researched his library, he would have found an unfamiliar paper in an obscure journal of an obscure botanist entitled "Experiments on Matching Plants" which was written in difficult German and mathematical. The table was full. Written in 1866, Darwin's genius might have led him to the answer he was looking for, and he certainly couldn't help but appreciate the hard work, sophistication, and results that came out of it.

This was the mystery of biology that Doppler's student Mendel had solved with great effort and care with the help of pea plants, after years of hard work in a monastery plot of land.

 

(to be continued)

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