Question

    When a leafy plant is under attack, it doesn’t  sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin, reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm. What the plants pump through the air is a mixture of chemicals known as volatile organic compounds, VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It’s a plant’s way of crying out. But is anyone listening? Apparently. Because we can watch the neighbours react.

Some plants pump out smelly chemicals to keep insects away. But others do double duty. They pump out perfumes designed to attract different insects who are natural enemies to the attackers. Once they arrive, the tables are turned. The attacker who was lunching now becomes lunch.

In study after study, it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant, but the neighbors, relatively speaking, stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn’t a true, intentional back and forth. Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There’s a whole lot going on.

1.What does a plant do when it is under attack?

A.It makes noises. B.It gets help from other plants.

C.It stands quietly D.It sends out certain chemicals.

2.What does the author mean by “the tables are turned” in paragraph 3?

A.The attackers get attacked.

B.The insects gather under the table.

C.The plants get ready to fight back.

D.The perfumes attract natural enemies.

3.Scientists find from their studies that plants can ________.

A.predict natural disasters

B.protect themselves against insects

C.talk to one another intentionally

D.help their neighbors when necessary

4.What can we infer from the last paragraph?

A.The world is changing faster than ever.

B.People have stronger senses than before

C.The world is more complex than it seems

D.People in Darwin’s time were imaginative.

Answer

1.D

2.A

3.B

4.C

【解析】

本文是一篇说明文。研究发现，当多叶植物受到攻击时，它们不会坐以待毙，会发出VOCs，以此来保护自己或者与周围的植物通过化学物质进行交流。

1.细节理解题。根据“reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm”可知，当植物受到伤害时，会分泌一种特殊的化学物质。故选D。

2.词义猜测题。根据“Once they arrive,the tables are turned. The attacker who was lunching now becomes lunch”，一旦它们到达这里， 然后这些攻击者就会成为植物的午餐，根据语境，故选A。

3.细节理解题，根据“ In study after study, it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant, but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do”，可知，植物在必要的时候会通过分泌化学物质，通知周围的植物保持警惕。故选B。

4.推理判断题。根据“imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There’s a whole lot going on”可知，这个世界远比我们看到或听到的更热闹、更亲密，我们认知能力有限，有很多事仍在继续发生，远比我们想象的要复杂。故选C。