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 which are called 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?Exactly.Because we can watch the neighbours react.

Some plants release 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 communication.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(親密的) than the world we can see and hear. Our senses are weak. The world is .

1.Does a leafy plant sit quietly when it is under attack?

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

3.How can scientists know that there is someone listening to the crying?

4.What does the author mean by “the tables are turned” in paragraphs 3?

5.From the scientists' studies, can plants protect themselves against insects or really talk to each other?

6.What can be filled in the blank at end of the passage?

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Choose the best answer(根據(jù)短文內(nèi)容,選擇恰當(dāng)答案)

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