問題詳情：
Plastic-Eating Worms
Humans produce more than 300 million tons of plastic every ye
ar. Almost half of that winds up in landfills(垃圾填埋場), and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, But a new study suggests an answer may lie in the stomachs of some hungry worms.
Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms’ chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊狀物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass — apparently broken down by enzymes (酶) from the worms’ stomachs. Their findings were published in Current Biology in 2017.
Federica Bertocchini, co-author of the study, says the worms’ ability to break down their everyday food — beeswax — also allows them to break down plastic. ＂Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, ＂she explains, ＂The wax worm evolved a method or system to break this bond. ＂
Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(腸道微生物)?
Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂
43．What can we learn about the worms in the study?
A．They take plastics as their everyday food.
B．They are newly evolved creatures.
C．They can consume plastics.
D．They wind up in landfills.
44．According to Jennifer DeBruyn, the next step of the study is to .
A．identify other means of the breakdown
B．find out the source of the enzyme
C．confirm the research findings
D．increase the breakdown speed
45．It can be inferred from the last paragraph that the chemical might .
A．help to raise worms
B．help make plastic bags
C．be used to clean the oceans
D．be produced in factories in future
46．What is the main purpose of the passage?
A．To explain a study method on worms.
B．To introduce the diet of a special worm.
C．To present a way to break down plastics.
D．To propose new means to keep eco-balance.
【回答】
43．C
44．B
45．D
46．C
【解析】
【分析】
本文為説明文。文章介紹了一種吃塑料的蟲子大蜡螟，它胃中的酶能夠降解塑料，這為解決塑料污染提供了新的途徑。
43．細節理解題。根據文章第三段Federica Bertocchini, co-author of the study, says the worms’ ability to break down their everyday food — beeswax — also allows them to break down plastic.可知，研究結果發現，蠕蟲分解日常食物的能力讓它們可以分解塑料，也就是説它們可以消費塑料。故選C。
44．細節理解題。根據文章第四段The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(腸道微生物)?可知，下一步研究是辨清分解的原因，查明這種酶來源於哪裏，是蟲子自己產生的還是它腸道里的微生物產生的。故選B。
45．推理判斷題。根據文章最後一段But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂可以推斷出，Bertocchini希望這種化學物質將來能在工業生產中使用，而不是僅僅依靠蠕蟲來分解塑料。故選D。
46．寫作意圖題。根據文章第一段最後一句So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.可知，有一種新的方法被用於分解塑料。再根據最後一段最後一句But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂可知，Bertocchini希望將這種方法推廣到工業中。由此可以推知寫作意圖為介紹一種分解塑料的方法。故選C。
點睛：根據不同文體，推斷目的意圖。不同的文章可能有不同的寫作目的，通常作者的寫作目的有以下三種：1) to entertain readers（*讀者，讓人發笑），常見於故事類的文章。2) to persuade readers（説服讀者接受某種觀點），常見於廣告類的文章。3) to inform readers（告知讀者某些信息），多見於科普類﹑新聞報道類﹑文化類或社會類的文章。閲讀時要善於根據文章的文體來學會推斷作者的情感態度和目的。本題的最後一題為寫作意圖題。文章為説明文，主要介紹了一項新的研究發現---蠕蟲可以分解塑料。因此可以推着寫作意圖是告知、告訴讀者一種新的分解塑料的方法。
知識點：科普知識與現代技術
題型：閲讀理解
