A
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 neighbouring 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 neighbours.The damage is usually more serious on the first plant,but the neighbours,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 neighbours 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.
语篇解读:本文是一篇说明文。文章主要介绍了植物受到袭击时会释放出某种化学物质来保护自己并“告知”附近的植物。
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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.
解析:选D 细节理解题。根据第一段中的reported that young maple trees getting bitten by insects send out a particular smell that neighbouring plants can get.These chemicals come from the injured parts of the plant and seem to be an alarm.可知,植物受到伤害时会散发出一种特殊的气味,而这种特殊的气味就是某些化学物质。
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.
解析:选A 句意理解题。根据第三段中的They pump out perfumes designed to attract different insects who are natural enemies to the attackers.以及画线部分后的The attacker who was lunching now becomes lunch.可知,画线部分的意思是:袭击者受到了它的天敌的袭击。
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 neighbours when necessary
解析:选B 推理判断题。根据第三段中的Some plants pump out smelly chemicals to keep insects away.和They pump out perfumes designed to attract different insects who are natural enemies to the attackers.可知,植物能保护自己免受昆虫的伤害。
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 more imaginative.
解析:选C 推理判断题。根据最后一段内容可知,达尔文设想了一个远比现实世界更繁忙、更喧嚣和更亲密的世界,而我们的感官却非常弱,我们还有很长的路要走。由此可知,世界似乎比它看上去的样子更复杂。