Plants may not have eyes and ears,but they can recognize their siblings (兄弟姐妹),and researchers at the University of Delaware have discovered how.The ID system lies in the roots and the chemical signals they secrete (分泌).
Canadian researchers published that sea rocket,a common seashore plant,can recognize its siblings.Susan Dudley observed that when siblings are grown next to each other in the soil,they “play nice” and don’t send out more roots to compete.However,the moment one of the plants is thrown in with strangers,it begins competing with them by rapidly growing more roots to take up the water and mineral nutrients in the soil.
After reading Dudley’s study,Bais decided to find the method behind the sibling recognition.Working in his laboratory,Bais and his doctoral student Meredith Biedrzycki set up a study with wild populations of Arabidopsis thaliana.In a series of experiments,young seedlings were exposed to liquid media containing the root secretions from siblings,from strangers,or only their own secretions.The length of the longest lateral (側面的) root was measured.The exposure of plants to the root secretions of strangers induced (引誘) greater lateral root formation than exposure of plants to sibling secretions.Strangers planted next to each other are often shorter,because so much of their energy is directed at root growth.Because siblings aren’t competing against each other,their roots are often much shallower (淺的).
Biedrzycki did the painstaking laboratory research,observing more than 3,000 plants involved in the study every day for seven continuous days and documenting the root patterns.“Arabidopsis roots are nearly translucent (半透明的) when they are young and were also twisted when I removed them from plates,”Biedrzycki notes.“This manuscript (手稿) is very important for my research since the focus of my thesis project is understanding the biochemical ways behind root secretions.”
The research also may have implications for the home gardener.“Often we’ll put plants in the ground next to each other and when they don’t do well,we blame the local garden center where we bought them or we attribute their failure to a germ,”Bais says.“But maybe there’s more to it than that.”
小題1:Which of the following would be the best title for this passage?
A.A Great Biology Researcher
B.Plants Recognize Their Siblings
C.Plants’ Roots and Secretions
D.A Research on Plants
小題2:What encouraged Bais to study the sibling recognition?
A.Sea rocket.
B.Plants’ sensing system.
C.Biedrzycki’s thesis project.
D.Dudley’s study.
小題3:What does the underlined word “painstaking” in Paragraph 4 probably mean?
A.Important.B.Adventurous.
C.Careful.D.Hard­working.
小題4:What can we infer from the last paragraph?
A.The local garden center should be blamed when plants can’t grow well.
B.The local garden center often sells low quality seeds to customers.
C.Plants in the home garden can’t grow well because of the germ and seeds.
D.Competing against strangers,plants in the home garden can’t grow well.

小題1:B
小題2:D
小題3:D
小題4:D

小題1: B
解析 標題歸納題。文章第一段第一句就開篇點題,植物可能沒有眼睛和耳朵,但他們認識自己的“兄弟姐妹”。下面所有內容都是圍繞這一中心展開的。
小題2: D
解析 細節(jié)理解題。根據(jù)第三段第一句可知,在看了Dudley的研究發(fā)現(xiàn)后,Bais決定找出植物識別同胞的方法,故D項正確。
小題3: D
解析 詞義猜測題。文章第四段第一句指出,Biedrzycki連續(xù)花費7天時間來研究、觀察3 000多種植物,由此推知painstaking為hard­working之意。
小題4: D
解析 推理判斷題。在文章最后一段作者提到,當家中花園里的植物生長得不好的時候,人們經(jīng)常會責怪花卉商店或者認為細菌太多。而最后一句作者又暗示,花園里面的植物生長得不好有可能是因為花園里種植了不同種類的植物,它們之間相互競爭,注重根部的生長,從而生長得不好。
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A.decoratingB.superficialC.expressiveD.demanding
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A.whether or not one looks good or bad, it doesn' t affect much one' s managerial career
B.in one' s managerial career, he may deal with cases like assets and liabilities
C.in one' s managerial career, he may rarely deal with cases like assets and liabilities
D.whether or not one looks good or bad, it may affect much one' s managerial career
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A.people do not realize the importance of looking one' s best
B.women in pursuit of managerial jobs are not likely to be paid well
C.good -looking women aspire to managerial positions
D.attractive people generally have an advantage over those who are not
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A.attractive women have tremendous potential impact on public job
B.good-looking women always get the best of everything
C.being attractive is not always an advantage for women
D.attractive women do not do as well as unattractive women in managerial positions
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If you are sitting at a desk, place the palm of your hand on the desk, and take a moment to focus on what the surface of the desk feels like. Is it hot or cold, rough or smooth? Put all of your attention on the sensations in your palm, on how the desk feels underneath your hand. If you are not at a desk, do the same exercise by placing your palm on any nearby object—a wall, a chair, even your opposite arm.
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If you can ground yourself even for a moment in the present, you will break the cycle and feel instant relief. Paying attention to what objects in your environment feel like forces you to pay more attention to the present moment than to negative, anxiety—provoking (刺激的,誘發(fā)的)thoughts about the past or about the future.
Try using your other senses too:
Try closing your eyes for a second(don’t try this while driving!) and breathe deeply through your nose. What do you smell?
When eating, put all your attention on how your food tastes.
What do you hear? What little noises are there around you that you didn’t notice before?
Look closely at an ordinary object. Do you see anything you haven’t noticed before?
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A.you did something wrong in the past and wouldn’t forgive yourself
B.your mind is quick and bright when in a state of anxiety
C.you are thinking in a stupid way when anxious thoughts worries you a lot
D.you worried a lot and the anxious thoughts will increase your anxiety
小題2:The author advises to put your palm on the desk or any things nearby in order to ____
A.play a small trickB.feel the surface of the object
C.do some exercisesD.reduce your anxiety
小題3:The writer mentioned some senses that could be used to reduce stress except the _____.
A.sense of touchingB.sense of smellC.sense of humourD.sense of listening
小題4:Which of the following can be served as a title for the article?
A.Frist Aid to Anxiety----Senses
B.How Anxiety Works
C.The Cause of Anxiety—Senses
D.How to Deal with Anxiety

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