Wonderful clones full text don t teach the plan

To illustrate "cloning", the author uses three methods of explanation: examples, paraphrasing, and citations. Example:

Give examples that are more familiar to people in the plant and animal kingdoms to illustrate, and explain the difficult scientific knowledge concisely and easily understandable; Definition: Traceability and interpretation of the term cloning; Quote: The story of Sun Wukong plucking a handful of monkey hair and conjuring a large group of monkeys in "Journey to the West" vividly illustrates what "cloning" is all about.

Before and after the birth of the cloned crucian carp" explains that the arrangement of the order shows the author's writing skills. There are two threads in this section: one is to write from China's "cloning experiments" to foreign "cloning experiments", which highlights the achievements and contributions of Chinese scientists in cloning research; The second is to write "cloning experiments" from fish, amphibians to mammals, reflecting the scientists' "never-ending pursuit of science", which is a process of continuous exploration, and also provides a scientific basis for the birth of "cloned sheep 'Dolly'" below, and paves the way for writing.

The birth of the cloned sheep has caused a sensation in the world for two main reasons: first, it marks a new progress and a major breakthrough in cloning research, and "this result proves that the so-called highly differentiated cells in the animal body that perform special functions and have a specific morphology have the same potential ability to develop into a complete individual as a fertilized egg."

That is, animal cells, like plant cells, are also totipotent. "The second is that it can be both a blessing for humanity and a bad omen for humanity, that is, it can be both good and harmful to mankind.

The text mainly writes about cloning technology from three aspects: for the benefit of mankind. First, cloning can be effective in breeding "high value-added livestock"; second, cloning can be used to save rare animals; Third, cloning is of great significance for the prevention and treatment of human diseases and the extension of life expectancy.

1. "Cells from the blastocyst stage of crucian carp are artificially cultured, and after 385 days and 59 generations of continuous subculture, the nucleus is sucked out from the cultured cells under a microscope with a glass tube with a diameter of about 10 microns. ”

2. "Of the 189 cells that have been nucleated, only two hatched fry, and in the end, only one juvenile survived the storm and grew into an 8-centimeter-long crucian carp after more than 80 days of culture. ”

3、“…The nuclei of the intestinal epithelial cells, liver cells, and kidney cells of the tadpoles are removed by advanced surgical procedures, and the nuclei of these cells are precisely placed into the egg cells, whose nuclei have been damaged by ultraviolet light. ”

4. "After hundreds of gray, black, and white operations, the white mouse finally gave birth to three little gray mice. ”

5. "After 247 failures, in July 1996 they got a cloned female baby sheep named 'Dolly'. ”

6、“…Use a very fine pipette to remove the nucleus from the egg cell. ......It is immediately sent into the egg cells of the 'Scottish black-faced sheep' from which the nucleus was removed. ......The embryo is then cleverly implanted into the womb of another ewe. ”

1.The first is to provide "accessories" for people themselves, the second is to save the endangered and rare animals, and the third is to facilitate people to study cancer biology, immunology, and human lifespan.

2.It shows that cloning technology will bring great benefits to human beings, and the cloned organisms contain many beneficial substances with high added value.

3.It is said that cloning technology has advantages and disadvantages, and the advantage is that it can provide people with "accessories" for themselvesBut it can also cause chaos in society and provide opportunities for criminals to take advantage of.

4.The benefits and effects of cloning technology have benefited mankind.

"Wonderful Clone" was selected into the 2014 edition of the junior high school Chinese textbook. The article "The Wonderful Clone" uses four subheadings to make the content of the whole text hierarchical and organized. The article first writes about the meaning of cloning, then writes about cloning experiments, then writes about the development of cloning, and finally writes about the benefits of cloning to mankind and thoughts on cloning.

The context of the text is very clear, which shows that things are advancing step by step.