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1、教 案授课单元Unit 8 Book 2 本（章）节授课方式课堂讲授（ ） 实践课（ ）教学时数6授课要点本 （章） 节 教 学 目 标1. master the basic language and skills necessary to ask for and give reasons;2. understand the main ideas of Text A, Text B and Text C, and master the useful sentence structures and words and expressions found in the exercises rele
2、vant to the first two texts3. know how to use the inverted order4. know how to write an email5. understand paragraph development 教 学 重 点 和 难 点In the Listening and Speaking section, learn how to ask for and give reasons. In the Reading and Writing section, read three passages about science and techno
3、logy. Text A was written at the turn of the 21st century and the writer predicted the top five scientific developments of the coming century. Text B concerns issues of safety that must be guaranteed when the frontier of science and technology is being pushed back. Text C deals with the issue of recy
4、cling.思考题或作 业1. What do you think of the writers predictions about the 21st century? Use your imagination to discuss peoples lives in the future when the writers predictions may come true. 2. Can you add more predictions to those of the writer? Make your own predictions to your classmates and see if
5、 any of them coincides with (与不谋而合) your classmates.教学内容与组织安排1st periodText A (Global Reading)2nd periodText A (Detailed Reading)3rd periodGrammar Review 4 th periodPractical Writing 5th periodText B6th periodImprove Your Reading Skills Part 1 Text A Study Background knowledge 1) James Trefil As an
6、award-winning author and physicist, James Trefil has written more than 25 books on a range of science topics. Hes a contributor to National Public Radio and Smithsonian Magazine, and a physics professor at Virginias George Mason University, U.S.A.The 20th century produced scientific and technologica
7、l change at a dizzying pace-greater than in any other century in history. But the 21st century, the dawn of the new millennium, may well see even more dramatic change driven by advances in science and technology. On these pages are my predictions for the top scientific developments well see in the n
8、ext 100 years, in the order I think theyll happen. 2) Modern Science (20th century)a. Genetics At the beginning of the 20th century, the life sciences entered a period of rapid progress. Mendels work in genetics was rediscovered in 1900, and by 1910 biologists had become convinced that genes are loc
9、ated in chromosomes, the threadlike structures that contain proteins and deoxyribonucleic acid (DNA). During the 1940s American biochemists discovered that DNA taken from one kind of bacterium could influence the characteristics of another. From these experiments, it became clear that DNA is the che
10、mical After American biochemist James Watson and British biophysicist Francis Crick established the structure of DNA in 1953, geneticists became able to understand heredity in chemical terms. Since then, progress in this field has been astounding. Scientists have identified the complete genome, or g
11、enetic catalog, of the human body (see Human Genome Project). In many cases, scientists now know how individual genes become activated and what effects they have in the human body. Genes can now be transferred from one species to another, side-stepping the normal processes of heredity and creating h
12、ybrid organisms that are unknown in the natural world (see Transgenic Organism).b. MedicineAt the turn of the 20th century, Dutch physician Christiaan Eijkman showed that disease can be caused not only by microorganisms but by a dietary deficiency of certain substances now called vitamins. In 1909 G
13、erman bacteriologist Paul Ehrlich introduced the worlds first bactericide, a chemical designed to kill specific kinds of bacteria without killing the patients cells as well. Following the discovery of penicillin in 1928 by British bacteriologist Sir Alexander Fleming, antibiotics joined medicines ch
14、emical armory, making the fight against bacterial infection almost a routine matter. Antibiotics cannot act against viruses, but vaccines have been used to great effect to prevent some of the deadliest viral diseases. Smallpox, once a worldwide killer, was completely eradicated by the late 1970s, an
15、d in the United States the number of polio cases dropped from 38,000 in the 1950s to less than 10 a year by the 21st century. By the middle of the 20th century scientists believed they were well on the way to treating, preventing, or eradicating many of the most deadly infectious diseases that had p
16、lagued humankind for centuries. But by the 1980s the medical communitys confidence in its ability to control infectious diseases had been shaken by the emergence of new types of disease-causing microorganisms. New cases of tuberculosis developed, caused by bacteria strains that were resistant to antibiotics. New, deadly infections for which there was no known
