Every electronic gadget (小玩意) needs good memory. A music player stores songs, albums and playlists. A computer holds schoolwork and programs and remembers how far a player has advanced in his or her favorite game. Mobile phones store names, numbers and hundreds of texts.
Now, scientists in California say they have come up with a way to turn a living cell into a memory device.
It can store only one tiny bit of information, but it’s a start. In the future, a cell-based gadget might travel through the body and record measurements. The benefit to human health could be big: the right tool, for example, might record the earliest signs of disease.
Doctors, scientists and other curious people want to know what is happening inside the body, even at levels that can’t be seen by the naked eye. So far, there is no device small enough to travel through the bloodstream.
If normal machines won’t do the trick, perhaps biology will. Scientists who work in the field of synthetic (合成的) biology are trying to find ways to turn living things into human tools. In the case of the new memory device, bioengineers from Stanford University used the genetic material inside living cells to record information.
This genetic material consists of DNA. Found in nearly every cell, DNA carries all of the information that keeps a living thing alive.
In the new experiment, the researchers turned DNA from bacteria(細菌) into a switch. They “flip (翻轉(zhuǎn))” a small section of DNA. Then, using the same procedure (過程) , the scientists flip the section again—returning it into its normal structure.
Using these DNA switches, “We can write and erase DNA in a living cell,” bioengineer, Jerome Bonnet, explained to Science News.
It might take years before his team or others identity whether a DNA-based memory device might be practical. Right now, it takes one hour to complete a flip. That is far too long to be useful. Plus, a flipped section has a very small little memory—less than what a computer uses to remember a single letter.
“This was an important proof that it was doable,” Bonnet told Science News. “Now we want to build a more complex system, something that other people can use.”
小題1:What is the aim of listing the electronic things in the first paragraph?
A．To make the passage more fashionable.
B．To show how electronic things have memory.
C．To discuss things in detail.
D．To make the subject of the text more understandable.
小題2:What is possible future benefit of the cell-based gadget for people?
A．To detect disease at the earliest point.
B．To help improve the memory.
C．To help people build a body.
D．To replace many electronic gadgets.
小題3:What is the object being researched?
A. The cells of bacteria.         
B. The DNA of bacteria.
C. A section of bacteria.         
C. The nucleus of bacteria.
小題4:What do we know about a flipped section of DNA?
A．It has a very small memory.
B．It can function as a computer.
C．It has one letter in it.
D．It takes a day to complete it.

小題1:D
小題2:A
小題3:B
小題4:A

試題分析：本文主要介紹了科學(xué)家已經(jīng)成功把活細胞植入了記憶裝置以及現(xiàn)在科學(xué)家正在研究細菌的DNA。
小題1:推斷題。第一自然段列舉電子事物的目的是使得這篇文章的主題更容易理解，故選D。
小題2: 細節(jié)題。根據(jù)It can store only one tiny bit of information, but it’s a start. In the future, a cell-based gadget might travel through the body and record measurements. The benefit to human health could be big: the right tool, for example, might record the earliest signs of disease.可知它的好處在于可以早期發(fā)現(xiàn)疾病，故選A。
小題3:細節(jié)題。根據(jù)In the new experiment, the researchers turned DNA from bacteria(細菌) into a switch. They “flip (翻轉(zhuǎn))” a small section of DNA. Then, using the same procedure (過程) , the scientists flip the section again—returning it into its normal structure.可知正在被研究的物體是細菌的DNA，故選B。
小題4: 細節(jié)題。根據(jù)That is far too long to be useful. Plus, a flipped section has a very small little memory—less than what a computer uses to remember a single letter.故選A。
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科目：高中英語 來源：不詳 題型：閱讀理解

(2013·高考安徽卷，B)Using too much water or throwingrubbish into our rivers are clear ways that humans can put our water supply in danger，but we also affect our water supply in less obvious ways.You may wonder how paving(鋪砌) a road can lead to less useable fresh water.A major part of the water we use every day is groundwater.Groundwater does not come from lakes or rivers.It comes from underground.The more roads and parking lots we pave，the less water can flow into the ground to become groundwater.
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Thinking about the way we use water every day can make a big difference，too.In the United States，a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live，but there’s a lot we can do to lower the number.
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小題1:Which of the following is most likely to lead to less groundwater?
A．Using river water.
B．Throwing batteries away.
C．Paving parking lots.
D．Throwing rubbish into lakes.
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A．All water shortages are due to human behavior.
B．It takes a lot of effort to meet our water needs.
C．There is much we can do to reduce family size.
D．The average family in America makes proper use of water.
小題3:The last paragraph is intended to________.
A．show us how to fix leaks at home
B．tell us how to run a dishwasher
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D．suggest what we do to save water at home
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B．how much we depend on water to live
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科目：高中英語 來源：不詳 題型：閱讀理解

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Another cause that makes animals become endangered is over-fishing or over-hunting. Over-hunting whales led to near extinction of many species of whales.
The introduction of a non-native species to a habitat may make animals become endangered. The native species may not defend against a new one, and the effects can be dangerous. In Australia, the introduction of the common house cat led to the extinction of the red-fronted parakeet and has seriously damaged the populations of several small animals.
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A．Native species are likely to die from the new diseases.
B．It’s hard for non-native species to survive.
C．Non-native species will take up more space.
D．Native species are so powerful for non-native species.
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A．loss of habitatB．harmful chemicals
C．forest cuttingD．unfamiliar diseases
小題5:We can infer from the last paragraph that ______.
A．humans are to blame for species extinction
B．small animals mean little to the whole food chain
C．protection of the honeybee has cost billions of dollars
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科目：高中英語 來源：不詳 題型：閱讀理解

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TV often teaches us a lot of important information as well about escaping from danger. Watch and learn. (1) If anyone is running after you down a passage, you will find that boxes have been conveniently placed near all the walls you need to jump over. (2) If you are tall and handsome, you can run from any number of armed criminals, and every shot will miss you.
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TV even teaches us about TV. Whenever anyone turns on a TV, it shows a news flash about someone they know. They then turn the box off immediately after that news item.
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A．humorB．sympathyC．deep concernD．medical knowledge
小題2: We can learn from Paragraph 3 that in the real world________.
A．bad things cause people to break down in the rain
B．bad things never happen on dark and stormy nights
C．people with emotional problems like to walk in the rain without umbrellas
D．you can’t hear the crack of lightning and see the accompanying flash exactly at the same time
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A．The program shown is always about the importance of TV.
B．The person always turns off the TV when it’s time for news.
C．The news shown is always about someone the person knows.
D．TV always shows news about famous people.
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B．What happens in TV is quite different from reality.
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小題1:According to the passage, a person, who is not willing to change his mind and hard to deal with, probably sleeps           .
A．on his sideB．on his backC．curled upD．on his stomach
小題2:If a person prefers to sleep curled up rather than on his back, he may be well content to    .
A．do things personally.B．stay alone
C．keep things secretD．trust others easily
小題3:Which of the following people, in the author’s opinion, most likely have personalities opposite to each other ?
A．The people sleeping on their stomachs and those sleeping on his backs.
B．The people sleeping on their sides and those sleeping curled up.
C．The people sleeping on their backs and those sleeping on their sides.
D．The people sleeping curled up and those sleeping on their stomach.
小題4:What the author mainly intends to tell us is that            .
A．one’s sleeping position has something to do with one’s character.
B．everyone has got both real and secret personalities.
C．the position in which one goes to sleep is the most important one.
D．when awake, one does not show one’s secret personality.

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科目：高中英語 來源：不詳 題型：閱讀理解

Some students get so nervous before a test; they do poorly even if they know the material. Sian Beilock has studied these highly anxious test-takers.
Sian Beilock: “They start worrying about the consequences. They might even start worrying about whether this exam is going to prevent them from getting into the college they want. And when we worry，it actually uses up attention and memory resources. I talk about it as your cognitive horsepower that you could otherwise be using to focus on the exam.”
Professor Beilock and another researcher，Gerardo Ramirez，have developed a possible solution. Just before an exam，highly anxious test-takers spend ten minutes writing about their worries about the test.
Sian Beilock: “What we think happens is when students put it down on paper，they think about the worst that could happen and they reappraise the situation. They might realize it’s not as bad as they might think it was before and，in essence(本質(zhì)上)，it prevents these thoughts from popping up when they’re actually taking a test.”
The researchers tested the idea on a group of twenty anxious college students. They gave them two short math tests. After the first one, they asked the students to either sit quietly or write about their feelings about the upcoming second test.
The researchers added to the pressure. They told the students that those who did well on the second test would get money. They also told them that their performance would affect other students as part of a team effort.
Professor Beilock says those who sat quietly scored an average of twelve percent worse on the second test. But the students who had written about their fears improved their performance by an average of five percent.
Next, the researchers used younger students in a biology class. They told them before final exams either to write about their feelings or to think about things unrelated to the test.
Prefessor Beilock says highly anxious students who did the writing got an average grade of  B+，compared to a B－ for those who did not.
Sian Beilock: “What we showed is that for students who are highly test-anxious，who’d done our writing intervention(排解)，all of a sudden there was no relationship between test anxiety and performance. Those students most likely to worry were performing just as well as their classmates who don’t normally get nervous in these testing situations.”
But what if students do not have a chance to write about their fears immediately before an exam or presentation? Professor Beilock says students can try it themselves at home or in the library and still improve their performance.
小題1:Which of the following is TRUE?
A．The result in the math test agrees with that in the biology test.
B．In the first math test, students who sat quietly performed better.
C．In the second math test, students who wrote about their feelings did worse.
D．Some college students are highly anxious test-takers while others are not in the tests.
小題2:What may happen if students have the problem of test anxiety?
A．Test anxiety is sure to cause students to fail the test.
B．Test anxiety can improve students’ performance to some degree.
C．Students’ attention and memory resources run out when worried.
D．Students may not be admitted into their favorite college if worried
小題3:The result of the research suggests that ________．
A．proper amount of burden may turn out to be a good thing
B．facing the fears bravely may help one to achieve more
C．a(chǎn)voiding facing the problem may contribute to relaxation
D．taking no action before difficulty may result in success
小題4:What is the main idea of the passage?
A．It is important for students to overcome test anxiety.
B．Anxious students overcome test anxiety by writing down fears.
C．It is a common practice for students being worried before a test.
D．Being worried before tests does harm to students’ performance.

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科目：高中英語 來源：不詳 題型：閱讀理解

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Ozone is particularly harmful to plants because it damages the pores(氣孔)  on leaves，called stomata,which plants use to regulate how much water evaporates from the leaves．That，in turn，affectS how much water a plant must take up through its roots．Changes in water uptake by plants have been documented in other parts of the world，including the United States，as having major impacts on regional groundwater and surface water supplies．
In studies of the long-term productivity of plants，Hanqin Tian and some of his colleagues show that ozone pollution,along with climate change，has been lowering plant productivity in China,which reduces the amount of carbon and other pollutants that the plants Can absorb to fight all the emissions from the burning offossil fuels．
The worst effects on plants are likely to be in areas where the growing pollution problem is just fairly new, said Arthur Chappelka, also a plant researcher at Auburn University．Some plants are more resistant to pollutants than others，he said，and the plants that are living today in long-polluted urban areas are likely to be only those that are very pollution tolerant．
Away from the cities, however, where crops are necded to feed China’s yast population, the effeets of the growing pollution on crops is a significant concern.
“In some ways it affects the crop production and food securiy of China,”said Hanqin Tian.“Air quality is really important for human health, plants and ecosystem and sustainability.”
The problem is bound to get worse as China continues to develop economically, he said, and so he and other researchers continue to urge the Chinese government to take action to reduce emissions from cars and industries.
小題1:ozone does harm to plants mainly by ________.
A．exposing them to strong sunlight
B．damaging the structure of their leaves
C．a(chǎn)dding more pores to the roots
D．making the land unfit for the plants to grow
小題2:Which of the following statement does Hanqin Tian support?
A．Ozone pollution has increased 1 6 times in the past 30 years．
B．Ozone pollution has lowered plant productivity alone．
C．Plants can take in a large amount of carbon and other pollutants．
D．The toxic air has few effects on food supply in China．
小題3:What Can we infer from the passage?   
A．Healthy foods are not available in Beijing．
B．Some kinds of plants aren’t affected by air pollution．
C．Crops in China are hard to feed its large population．
D．People should stop developing economically
小題4:According to the passage，the Chinese govemment should
A．care more about developing economy
B．reduce the number of cars and industries
C．continue to make more researches
D．take measures to reduce carbon emissions
小題5:What′S the best title of the passage?
A．Polluted air damages plants and crops
B．Air pollution is becoming more serious
C．China’s air pollution and climate changes
D．Food security in China

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科目：高中英語 來源：不詳 題型：閱讀理解

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Despite the controversy, the U．S．postal service began using Kamen's invention a month after its appearance, and a factory was built with plans to produce about 40,000 Segways every month．The argument is still on whether the Segway will be remembered as the greatest invention since the light bulb, or just another forgettable electronic device．Anyway, trips to the local supermarket will never be the same again．
小題1:Which statement best describes the critics' reaction to the Segway?
A．Nothing but an electrical device．
B．A disappointing engineering mistake．
C．An expensive and disappointing invention．
D．Disappointing, but still a successful device．
小題2:Which is not a feature of the Segway?
A．One person at a time can ride on it．
B．It has two wheels with a single axle．
C．It is powered by electricity and can go up to 12mph．
D．Riders increase the speed by moving the handlebars
小題3:Some people expressed dissatisfaction with the Segway because of its______.
A．high costB．danger to traffic
C．being difficult to useD．contribution to laziness
小題4:Shortly after the Segway appeared, there were _________.
A．hopes for a larger model of it
B．no plans to do anything more with it
C．some discussions on the unforgettable device
D．plans to make tens of thousands of them a month

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科目：高中英語 來源：不詳 題型：閱讀理解

It’s common for parents to feel emotional when the moment comes for their child to leave home and go to university. Even parents who don’t speak about the event are likely to feel a sense of sadness because it’s the end of an era where you and your family were at the centre of your child’s world. As a parent you’ll probably continue to support your child in different ways, but the main job of raising your child is over. It’s a huge change for everyone involved.
There are a few things that you can do to make the transition easier. Plan carefully for your child’s departure and think about how you can help. Many parents take their child to university for the first time. If you decide to do that, be ready to feel a real wrench when the time comes to say goodbye. Your child will probably be as nervous as you are about the moment when you finally say goodbye – but that might not show!
Be positive and cheerful about the choice your child has made to continue studying, and plan to leave once you’ve unpacked the car and looked around your child’s new living accommodations. If you can, save your tears for the car – you’ll make things easier on your child and yourself.
The more you’ve invested in being a parent, the more you’ll feel a sense of loss, so the sadness you feel now is a sign that you’ve been a good mom or dad. Remind yourself that parenting is all about raising an independent and confident child who functions well without you. If your child quickly settles and starts enjoying himself, you should congratulate yourself.
It’s also only fair to allow yourself some time to grieve. Don’t expect to pick yourself up and move on straight away. But you may decide to find a hobby or sport to fill your extra time. Perhaps you’ve always wanted to learn a new language, go to yoga classes or take up swimming. You may decide to spend more time with family and close friends, who are likely to be feeling the absence of your child as well.
Agree on the best approach to staying in touch before your child leaves, and stick to your agreement. Try not to panic if your child doesn’t respond immediately – remember, they’re starting a new and busy life.
小題1:The underlined word “wrench” in Paragraph 2 means a feeling of ________.
A．sorrowB．regret C．a(chǎn)ngerD．love
小題2:What does good parenting consist of?
A．Supporting your child in different ways all the time.
B．Congratulating yourself when your child goes to college.
C．Preparing your child to stand on their own feet in the future.
D．Investing as much as possible in the growth of your child.
小題3:What’s NOT advised as the way to recover from your child’s departure?
A．Developing a new hobby or sport
B．Learning a new language.
C．Spending more time with close friends
D．Staying in touch with your child.
小題4:What would be an appropriate title for the whole passage?
A．Staying in Touch with Your Child
B．Preparing to Say Goodbye to Your Child
C．Dealing with Your Child Leaving Home for University
D．Life after Your Child Has Left Home for University

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