Question

    Though plastic shopping bags are cheap and useful, they cause widespread pollution. Now, we may have an unlikely helper to help clean up our garbage — a small wax worm.

The worm’s hidden skills were discovered by accident. About two years ago, Federica Bertocchini, a developmental biologist at the Spanish National Research Council and an amateur beekeeper, was cleaning out bees’ nest that had been filled with worms. She removed the worms and put them in a plastic bag while doing the cleaning. After finishing, she went back to the room where she had left the worms, and found they had escaped from the bag. When she checked, she saw that the bag was full of holes.

Realizing she may have made an important discovery, Bertocchini teamed up with other researchers to conduct further research. They began by placing 100 worms on some plastic bags and discovered that over a 24-hour period, the worms managed to chew through 92 milligrams of plastic. The researchers make an appropriate judgment that at this rate, the group of worms could  degrade (降解) an average-sized 5.5-gram plastic bag within a month. To rule out the possibility that chewing was causing the degradation, the researchers spread the soft wet substance inside the body of some recently dead worms on a sheet of plastic. Sure enough, even the liquid was able to eat through the material, confirming that the worms have plastic-digesting enzymes (酶).

While the news is certainly encouraging, not everyone is convinced. The Michigan State University’s Ramani Narayan believes the tiny pieces of microplastics released by the plastic-eating worms would pick up harmful substances and transport them up the food chain, causing, even more, harm to the environment and human health. Susan Selke, director of Michigan State University School of Packaging, is concerned that the worms will not be able to survive in an oxygen-free landfills where large amounts of waste material are buried under the earth.

However, Bertocchini is not planning to transport worm armies to landfills. Instead, the researcher wants to identify the enzyme that helps degrade the plastic. The researcher says, maybe we can find the molecule (分子) and produce it on an industrial level, rather than using a million worms in a plastic bag.

1.What did the experiment of using dead worms find out?

A.Worms’ chewing may cause the degradation.

B.A plastic-eating chemical exists in wax worms.

C.Dead worms are effective in dealing with plastic.

D.It takes a long time for worms to degrade plastic.

2.What is Ramani Naravan's attitude to Bertocchini's finding?

A.Objective B.Convinced C.Questioning. D.Optimistic.

3.What might Bertocchini focus her later research on?

A.The structure of plastic-degrading enzymes.

B.The use of other worms in disposing plastic.

C.Wax worms’ adaptability to the landfill environment.

D.The chance of producing wax worms on a large scale.

4.What is the best title for the text?

A.Can wax worms save the environment?

B.Wax worms have an appetite for plastic.

C.Why do wax worms have plastic-eating skills?

D.Hungry worms join the fight against plastic pollution

Answer

1.B

2.C

3.A

4.B

【解析】

这是一篇说明文。文章介绍喜欢吃塑料的蜡虫。通过研究发现这种虫子具有塑料消化酶，尽管虽然这个消息确实令人鼓舞，但并不是每个人都信服，有些人认为吃塑料的蠕虫释放出的微小塑料碎片会收集有害物质并将它们输送到食物链上，对环境和人类健康造成更大的危害。

1.推理判断题。根据第三段中To rule out the possibility that chewing was causing the degradation, the researchers spread the soft wet substance inside the body of some recently dead worms on a sheet of plastic. Sure enough, even the liquid was able to eat through the material, confirming that the worms have plastic-digesting enzymes (酶).“为了排除咀嚼导致退化的可能性，研究人员将这种柔软湿润的物质撒在一些刚死的蠕虫体内的一张塑料上。可以肯定的是，即使是液体也能吃掉这些物质，这就证实了蠕虫有塑料消化酶。”由此可知，用死虫做的实验发现“蜡虫体内存在一种能吃塑料的化学物质。”故选B。

2.推理判断题。根据第四段中While the news is certainly encouraging, not everyone is convinced. The Michigan State University’s Ramani Narayan believes the tiny pieces of microplastics released by the plastic-eating worms would pick up harmful substances and transport them up the food chain, causing, even more, harm to the environment and human health.“尽管这一消息确实令人鼓舞，但并非所有人都对此深信不疑。密歇根州立大学的Ramani Narayan认为，这些以塑料为食的蠕虫释放的微小塑料微粒会带走有害物质，并将其转移到食物链中，对环境和人类健康造成更大的危害。”由此可知，Ramani Naravan对Bertocchini的发现持“怀疑”态度。故选C。

3.推理判断题。根据最后一段中Instead, the researcher wants to identify the enzyme that helps degrade the plastic. The researcher says, maybe we can find the molecule (分子) and produce it on an industrial level, rather than using a million worms in a plastic bag.“相反，研究人员想要找出帮助降解塑料的酶。研究人员说，也许我们可以找到这种分子并进行工业化生产，而不是用一百万只蠕虫装在一个塑料袋里。”由此可知，Bertocchini后来的研究重点可能是塑料降解酶的结构。故选A。

4.标题判断题。根据第一段Though plastic shopping bags are cheap and useful, they cause widespread pollution. Now, we may have an unlikely helper to help clean up our garbage — a small wax worm.“虽然塑料购物袋便宜又有用，但它们造成了广泛的污染。现在，我们可能有了一个意想不到的帮手来帮我们清理垃圾——一只小蜡虫。”由此可知，B项Wax worms have an appetite for plastic.（蜡虫喜欢吃塑料。）为最佳标题。故选B。