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 (侧面的) root was measured.The exposure of plants to the root secretions of strangers induced (引诱) 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 (浅的).
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.”
【小题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 |
| A.Sea rocket. |
| B.Plants’ sensing system. |
| C.Biedrzycki’s thesis project. |
| D.Dudley’s study. |
| A.Important. | B.Adventurous. |
| C.Careful. | D.Hardworking. |
| 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. |
【小题1】B
【小题2】D
【小题3】D
【小题4】D
解析【小题1】 B
解析 标题归纳题。文章第一段第一句就开篇点题,植物可能没有眼睛和耳朵,但他们认识自己的“兄弟姐妹”。下面所有内容都是围绕这一中心展开的。
【小题2】 D
解析 细节理解题。根据第三段第一句可知,在看了Dudley的研究发现后,Bais决定找出植物识别同胞的方法,故D项正确。
【小题3】 D
解析 词义猜测题。文章第四段第一句指出,Biedrzycki连续花费7天时间来研究、观察3 000多种植物,由此推知painstaking为hardworking之意。
【小题4】 D
解析 推理判断题。在文章最后一段作者提到,当家中花园里的植物生长得不好的时候,人们经常会责怪花卉商店或者认为细菌太多。而最后一句作者又暗示,花园里面的植物生长得不好有可能是因为花园里种植了不同种类的植物,它们之间相互竞争,注重根部的生长,从而生长得不好。
科目:高中英语 来源: 题型:阅读理解
It is a wonderful morning,as I write this:hot,but without being too hot. Outside my window,I can see the sunniest sky of the year reflected in a huge natural expand of water. It is the kind of sun that makes you well aware of summer’s temporary nature —a reminder that if I am ever to go around to book this year's holiday,time is running out .
It is now close to four years since I last took a holiday. This is because I have come to the conclusion, over the course of my adult life, that I am not very good at it. You might say this sounds like saying you are not very good at drinking tea or listening to music. What could possibly be difficult about the natural act of putting your working life on hold for a couple of weeks and going somewhere to do nothing?
So what is my problem? On the surface, I'm probably a bit of homebody. And I just find the pressure of being on holidy too severe: it always feels like having a gun held to my head and being forced to have fun. Somehow, packing a carefully itemized list of possessions and meeting a scheduled flight has none of the excitement of suddenly deciding to take a day off and driving somewhere for the fun of it.
Thankfully, I am not alone. This summer, most of my friends have decided not to have a break. And a recent survey highlighted the downside(负面)of holidays, with the results shoeing that nearly two thirds of people found that the calming effects of a holiday wore off within 24 hours, as stress levels returned to normal. And this year's the Idler magazine published its book of awful holidays .Here you will find a list of the five most ecologically--damaging vacations it's possible to take, along with 50 horrible holidays experiences voted for on the idler website. Over the last decade, The Idler has become well known for promoting the idea of an easy, lazy life. The leisure(休闲)industry might seem an unlikely target of its criticism, but Dan Kienan, the book's editor, says that he was flooded with entries from readers for his list of awful holidays.
【小题1】According to the first paragraph We can know that the writer .
| A. has a strong desire to book a holiday |
| B. wishes that the weather would change |
| C. finds it is too late to enjoy the sunshine |
| D. realizes it’s time to decide whether to go on a holiday |
| A. people may find the man unbelievable |
| B. People think traveling is not so easy an act as drinking tea |
| C.The writer often regrets not taking a holiday. |
| D. The writer doesn't like drinking tea or listening to music |
| A. it usually takes too much time |
| B. he is tired of making preparations too much for holidays |
| C. it is far less enjoyable than breaks planned in advance |
| D. he feels embarrassed when other people are having fun but he isn't |
| A. pretend to enjoy their holiday |
| B. fail to relax while they are on holiday |
| C. feel that the benefits of going on holidays are limited |
| D. have made the some decision as the writer and most of his friends |
| A. damage the reputation of the magazine |
| B.prove his idea to be more popular than expected |
| C. indicate that his dislike of holidays is widely shared |
| D. foucs entirely on bad personal experiences of holidays |
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科目:高中英语 来源: 题型:阅读理解
Water runs downhill from mountaintops to streams to rivers to oceans. But downhill isn’t the only way that water moves .A new study measures how water travels from country to country for human consumption. This flow isn’t the type we usually think about .These scientists looked at the water used to grow and make the products which get shipped from nation to nation as imports or exports. They call this a flow of“virtual water(虚拟水)”.
We typically think about water as the liquid that flows from a tap. However,92%of the water used by people goes into growing crops,according to water researcher Arjen Hoekstra. He recently studied the hidden travels of virtual water used in products made from things like crops and meats .These products are shipped around the world.
For example.consider a sugary soft drink. Hoekstra estimated that to produce one half-liter of the drink requires between 170 and 310litersofthewater—about 95%—is used to grow and process the ingredients(原料).Another 4%goes into the packaging and labeling. In Hoekstra’s calculation, when one country produces a half-liter of soda and sells it abroad,it exports as much virtual water as would fill a large refrigerator.
According to Hoekstra’s new report,dry countries like Israel and Kuwait,both in the Middle East, get the majority of their virtual water from other countries,through imported products. More surprisingly, some wetter countries,like the Netherlands and the United Kingdom, also get the majority of their virtual water from other places. That means that most of the water used to grow or produce the products and food consumed in those countries came from other countries.
In the United States most of the virtual water used comes from American sources .In China even less of the water associated with its products
【小题1】What is the best title for the passage?
| A.Crops and Virtual Water | B.Import and Export of Water |
| C.Benefits of Virtual Water | D.Water’s worldwide travels |
| A.how water flows |
| B.what virtual water is |
| C.where virtual water exists |
| D.why water is imported and exported |
| A.how drinks are made | B.how virtual water is used |
| C.how virtual water is exported | D.how drinks are shipped |
| A.lsrael and America | B.America and the Netherlands |
| C.China and the United Kingdom | D.Kuwait and the Netherlands |
| A.science news report | B.book review |
| C.newspaper advertisement | D.science fiction story |
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科目:高中英语 来源: 题型:阅读理解
It was a village in India.The people were poor.However,they were not unhappy.After all,their forefathers had lived in the same way for centuries.
Then one day,some visitors from the city arrived.They told the villagers there were some people elsewhere who liked to eat frog’s legs.However,they did not have enough frogs of their own,and so they wanted to buy frogs from other places.
This seemed like money for nothing.There were millions of frogs in the fields around,and they were no use to the villagers.All they had to do was catch them.Agreement was reached,and the children were sent into the fields to catch frogs.Every week a truck arrived to collect the catch and hand over the money.For the first time,the people were able to dream of a better future.But the dream didn’t last long.
The change was hardly noticed at first,but it seemed as if the crops were not doing so well.More worrying was that the children fell ill more often,and,there seemed to be more insects around lately.
The villagers decided that they couldn’t just wait to see the crops failing and the children getting weak.They would have to use the money earned to buy pesticides(杀虫剂) and medicines.Soon there was no money left.
Then the people realized what was happening.It was the frog.They hadn’t been useless.They had been doing an important job—eating insects.Now with so many frogs killed,the insects were increasing more rapidly.They were damaging the crops and spreading diseases.
Now,the people are still poor.But in the evenings they sit in the village square and listen to sounds of insects and frogs.These sounds of the night now have a much deeper meaning.
(2010·辽宁,A)
【小题1】From Paragraph 1 we learn that the villagers ________.
| A.worked very hard for centuries |
| B.dreamed of having a better life |
| C.were poor but somewhat content |
| D.lived a different life from their forefathers |
| A.The frogs were easy money. |
| B.They needed money to buy medicine. |
| C.They wanted to please the visitors. |
| D.The frogs made too much noise. |
| A.The crops didn’t do well. |
| B.There were too many insects. |
| C.The visitors brought in diseases. |
| D.The pesticides were overused. |
| A.Happiness comes from peaceful life in the country. |
| B.Health is more important than money. |
| C.The harmony between man and nature is important. |
| D.Good old days will never be forgotten. |
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科目:高中英语 来源: 题型:阅读理解
Alex Taw,a 21yearold student from Wiltshire,England.He spent last summer like any other high school graduate—hanging out with friends,preparing for college,worrying about his university fees.While most of his peers gave up on their pipe dreams,he sat down with a notebook at home,and jotted down (草草记下) the question:How can I become a millionaire?
The result was the MillionDollarHomepage.com.Alex’s initial investment was 50 pounds to buy web space and a domain (领域) name.He divided the blank homepage into one million pixels (电脑上的像点),10,000 blocks of 100 pixels each.Each pixel was worth $1 with minimum purchase 100 pixels.Within a month Alex had earned some $37,000,enough for him to cover the entire cost of his forthcoming three years at university.In just a few months,he became a real millionaire.
How did he come up with the idea of the Million Dollar Homepage?
“Well,I was trying to think of a way to make some money before I started university,as I was about to take on a huge debt and I was already overdrawn (透支).Swift action was necessary!”He said.
He also added,“The important thing is that anything is possible—we are only limited by our imagination.I always had this belief that a good idea can be successful on its own.I think I’ve learnt that if we think deeper there are magical solutions hiding away for us to find.”
His personal philosophy around money is:Money is not everything,but it’s an essential part of the way we live.Having_some_removes_a_certain_amount_of_stress,but,unless_we_are_careful,it_can_create_a_new_type_of_stress.
He also said,“I still want to go to university.Aside from gaining knowledge about business,there are other reasons—exploring your interests,meeting new people,and being in a creative environment.”
Besides making contributions to society,he would try to encourage and inspire people to think of creative solutions to problems,whatever they are.
【小题1】According to the passage,which of the following is NOT an important factor for being a millionaire?
| A.Large imagination. | B.Quick action. |
| C.Great ambition. | D.Great investment. |
| A.Alex Taw is an American millionaire. |
| B.Alex Taw will graduate from university. |
| C.Alex Taw doesn’t work hard. |
| D.Alex Taw was not rich before. |
| A.The more money we have,the more stress we have. |
| B.Money can be of great help. |
| C.We should try our best to earn money. |
| D.Money is helpful in some way,but we should make full use of it. |
| A.Little Money Leads to Be a Millionaire |
| B.The Success Road to Be a Millionaire |
| C.Alex Taw:An Millionaire Boy |
| D.The MillionDollarHomepage.com |
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科目:高中英语 来源: 题型:阅读理解
Should you stay at home to look after your child,or return to work?
Maybe you don’t have the option.Combining work and motherhood is an issue faced by increasing numbers of women every day.
New research for the Institute for Economic and Social Research could solve this quandary once and for all.In short,it concludes that going back to work after the birth of a child can have a negative impact on the child’s development—unless you have lots of money.
“Growing up in a family in which the mother chooses to work appears to have some adverse consequences for children’s welfare,” the research says.However,it adds that extra money brought in by both parents can reduce the negative effect.The negative effect is also less apparent in children of bettereducated mothers.
The research by John Ermisch and Marco Francesconi is especially downbeat about welfare to work programmes,and especially,the prospects for the children of some single parents.
“It is hard to see anything but gloomy (阴暗的) prospects for the children of single parents (who are generally poor),” the researchers said.This is because in a common family where both parents work,extra money brought in by the mother’s working would compensate for less time spent with the children.
In contrast,the researchers said the effects of paternal (父亲的) employment were far more modest,but this did not mean that fathers had no role in shaping their children’s welfare.Money brought in by the father would be a major resource for helping children develop.
The research says,however,that before parents get too carried away by worrying about working,there are more important issues facing a child’s development.Parents’ personalities and emotional stability,parenting practices,and the friends and networks that children experience while growing up will be much bigger factors than whether their mothers work.
【小题1】The extra money brought in by both parents________.
| A.plays different roles in shaping a child’s welfare |
| B.can reduce the negative effect on a child |
| C.has negative effect on a child’s development |
| D.may damage the life of children |
| A.mothers should keep a balance between work and family life |
| B.the more money mothers make,the worse their children will be |
| C.mothers should make as much money as they can |
| D.it would be better for mothers to be with children at home |
| A.it doesn’t matter how much money a father brings home |
| B.education is the only factor in shaping a child’s welfare |
| C.money made by mothers can also contribute to a child’s wellbeing |
| D.mothers’ income can have a deeper effect on a child’s development |
| A.Whether mothers work is not worth considering. |
| B.The research shows family stability is important. |
| C.Parents should stop worrying about working. |
| D.More important factors are involved in a child’s development. |
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科目:高中英语 来源: 题型:阅读理解
When it comes to social behaviour,mammals are in a league of their own.Some birds may form pairs,or even cooperate to hunt,but the complexity (复杂性) of their relationships can hardly compare to those within a school of dolphins,a herd of elephants or a group of humans.What makes mammalian social groups different from a flock of starlings or a shoal of fish,is that in many cases the individuals could recognize each other.Although we may think that all elephants look pretty much the same,we can easily tell individuals of our own species apart and it has become clear through studies that the same is true of other species.Dolphins have their own signature whistles that act like “names”,and elephants can recognize and greet other individuals they have known but not seen for many years.This is something that only a few species of birds appear to be able to do.
Mammals in complex social groups not only recognize each other as individuals,but also they remember a lot of information about that individual.Social groups often rely on this memory—such as knowing who is dominant to whom,who is related to whom,and who has done what to whom in the past.It’s like remembering who you have lent money to or done a favour for,and who hasn’t repaid that money or has talked about you behind your back.You have to learn who to trust,who your friends are,and who to watch out for.
All this remembering goes on in a particular part of the brain called the neocortex (大脑皮层).If you compare the size of a mammal’s social group with the size of this part of the brain,you will find they are remarkably closely related.This area seems to take a long time to develop fully and animals in which it is very large take a very long time to grow up to adulthood.During this time,the youngster has to learn all the rules of social behaviour in their group and to piece together all the relationships between the group members:Knowledge that will be needed to avoid getting into trouble.
【小题1】What is special about a mammalian social group according to the passage?
| A.All the individuals cooperate to hunt. |
| B.The individuals can communicate with each other. |
| C.The individuals can recognize each other. |
| D.The individuals form closer relationship. |
| A.are cleverer than dolphins |
| B.can recognize other species |
| C.may mistake a member for another |
| D.have good memories |
| A.will have a long period of time before they become adults |
| B.will spend a shorter time learning the necessary knowledge |
| C.will learn the necessary knowledge much more easily |
| D.will have more difficulty in growing up as adults |
| A.can live a longer life |
| B.have a smaller social group |
| C.have a larger social group |
| D.have a greater body size |
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科目:高中英语 来源: 题型:阅读理解
With the crazy smog going on in China, businessmen are now ready to grope for your wallet. “Smog economy” is stimulating a shopping spree on certain products against the terrible weather. Now let’s see what we have on the list to help us through the crisis.
1. Masks
Well, I would say you had better stay indoors to save your lives. PM 2.5 just surged up to 750 in Beijing recently. 3M just sold 220,000 masks of a kind. No.1 best-selling products!
2. Air purifiers
This kind of products is rarely seen in Chinese households in the past. They have become a necessity now. I do like these little gadgets, but they are just too expensive.
3. Oxygen inhalers
I didn’t realize oxygen inhalers also get a cut in the smog economy. As a matter of fact, your oxygen uptake has nothing to with relieving (减轻) the impact of smog. It might even lead to oxygen poisoning when you inhale too much oxygen. So don’t get greedy.
4. Salt lamps
Compared to oxygen inhalers, salt lamps are even worse. Some stores are selling the products at several hundred yuan, saying that they can release negative ions(离子), reduce radiation levels and purify the air. The lamps mainly contain sodium chloride. The boiling point of sodium is about 800 degrees centigrade and that of candle is 500. So how on earth can negative ions be released at only 500 degrees?
5. Plants that absorb smog
Yeah, right. Plants Vs Smog. It is scientifically justified (证明) that some plants do absorb pollutants from the air. Money plants and calla lilies are among the best-sellers in the market. Even if they don’t work, it’s good to have some plants in the house anyway.
【小题1】According to the passage, smog _______.
| A.give some economic chances to businessmen |
| B.is very bad to economy |
| C.makes some crisis come out |
| D.have nothing to do with the economy |
| A.Giving up shopping. | B.Feeling down in shopping. |
| C.Having a lot to buy. | D.Buying something enthusiastically. |
| A.it may cause poisoning |
| B.it actually can’t release the negative ions |
| C.it reduces radiation level and makes the air dirty |
| D.the prize is very high |
| A.2. | B.3. | C.4. | D.5. |
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科目:高中英语 来源: 题型:阅读理解
Everyone has got two personalities—the one that is shown to the world and the other that is secret and real. You don’t show your secret personality when you’re awake because you can control your behavior, but when you’re asleep, your sleeping position shows the real you. In a normal night, of course, people frequently change their position. The important position is the one that you go to sleep in.
If you go to sleep on your back, you’re a very open person. You normally trust people and you are easily influenced by fashion or new ideas. You don’t like to upset people, so you never express your real feelings. You’re quite shy and you aren’t very confident.
If you sleep on your stomach, you are a rather secretive(不坦率的)person. You worry a lot and you’re always easily upset. You’re very stubborn(顽固的), but you aren’t very ambitious. You’re usually live for today not for tomorrow. This means that you enjoy having a good time.
If you sleep curled up (卷曲),you are probably a very nervous person. You have a low opinion of yourself and so you’re often defensive. You’re shy and you don’t normally like meeting people. You prefer to be on your own. You’re easily hurt.
If you sleep on your side, you have usually got a well-balanced personality. You know your strengths and weaknesses. You’re usually careful. You have a confident personality. You sometimes feel anxious, but you don’t often get depressed. You always say what you think even if it annoys people.
【小题1】According to the writer, you naturally show your secret and real personality .
| A.only in a normal night |
| B.only when you go to sleep |
| C.only when you refuse to show yourself to the word |
| D.only when you change sleeping position |
| A.He or she is always open with others. |
| B.He or she always likes new ideas earlier than others. |
| C.He or she is always easily upset. |
| D.He or she tends to believe in others. |
| A.He or she is careful not to offend others. |
| B.He or she doesn’t want to stick to his or her opinion. |
| C.He or she can’t be successful in any business. |
| D.He or she likes to bring others happiness. |
| A.He or she would rather be alone than communicate with you. |
| B.He or she is rarely ready to help you. |
| C.He or she prefers staying at home to going out. |
| D.He or she wouldn’t like to get help from you. |
| A.he or she always shows sympathy for people |
| B.he or she is confident, but not stubborn |
| C.he or she has more strengths than weaknesses |
| D.he or she often considers annoying people |
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