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总课时：52分钟
讲师介绍
黄鹏祥，执教于山西省太原市外国语学校。持有国家人事部口译证书与笔译证书。曾荣获中央电视台“希望之星风采大赛（教师组）”全国二等奖；第八届全国高中教师基本功大赛全国一等奖。
教学文本
选自《21世纪英文报·高三》总第721、722期
教学亮点
1、结合高三学生的学情，大容量快节奏地进行报纸阅读。直接针对高考学生的难点----科技文阅读。
2、学生在读报期间通过对文章的把握，猜测词义。同学通过上黑板呈现的方式，互帮互助，解决词汇层面的问题。小组活动中，让学生多用英语表达自己的观点，能用英语进行深层思考。
3、选取的报纸上2篇文章，角度新颖、时效性很强，同时针对高三毕业班，也链接了高考真题文章，作为对报纸科技文的拓展阅读。
（2018年北京高考,Passage C）
Plastic-Eating Worms
(P1) Humans produce morethan 300 million metric tons of plastic every year. Almost half of that windsup in landfills(垃圾填埋场), and up to 12 millionmetric tons pollute the oceans. So far there is no sustainable way to get ridof it, but a new study suggests an answer may lie in the stomachs of somehungry worms.
(P2) Researchers in Spainand England recently found that the worms of the greater wax moth can breakdown polyethylene, which accounts for 40% of plastics. The team left 100 waxworms on a commercial polyethylene shopping bag for 12 hours, and the wormsconsumed and broke down about 92 milligrams, or almost 3% of it. To confirmthat the worms' chewing alone was not responsible for the polyethylene breakdown,the researchers made some worms into paste (糊状物)and applied it to plastic films. 14 hours later thefilms had lost 13% of their mass—apparently broken down by enzymes(酶) from the worms' stomachs. Theirfindings were published earlier this year in Current Biology in 2017.
(P3) Federica Bertocchini, co-authorof the study, says the worms’ ability to break down their everyday food—beeswax—alsoallows them to break down plastic. “Wax is a complex mixture, but the basicbond in polyethylene, the carbon-carbon bond, is there as well,” she explains.“The wax worm evolved a method to break this bond.”
(P4) Jennifer DeBruyn, amicrobiologist at the University of Tennessee, who was not involved in thestudy, says it is not surprising that such worms can break down polyethylene.But compared with previous studies, she finds the speed of breaking down inthis one exciting. The next step, DeBruyn says, will be to identify the causeof the breakdown. Is it an enzyme produced by the worm itself or by its gutmicrobes(肠道微生物)?
(P5) Bertocchini agrees andhopes her team's findings might one day help employ the enzyme to break downplastics in landfills. But she expects using the chemical in some kind ofindustrial process—not simply “millions of worms thrown on top of the plastic.”
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黄鹏祥，山西省太原市外国语学校教师。持有国家人事部口译证书与笔译证书。2010年参加中央电视台"希望之星风采大赛（教师组）", 获全国二等奖。
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