IT’S never a real problem for us when the weather gets cold. We can put on more clothes, stay next to a fireplace, turn on the air conditioner or simply travel to a warmer city to spend the winter – people have many different ways of coping with the cold.
But things are not as easy for plants. Unlike humans, plants can’t move to escape the cold or generate heat to keep themselves warm. So how do they manage to survive the freezing winter?
It turns out that plants have their own strategies too, said a study published on Dec 22 in the journal Nature.
According to researcher Amy Zanne of George Washington University, US, the cold is a big challenge for plants. Their living tissues can be damaged when they freeze. “It’s like a plant’s equivalent to frostbite (冻疮),” Zanne told Science Daily. Also, the process of freezing and thawing (解冻) can cause air bubbles to form in the plant’s water transport system. “If enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant,” she explained.
To live through cold weather, plants have developed three traits, according to the study. Some plants, such as oak trees, avoid freezing damage by dropping their leaves before the winter chill sets in – effectively shutting off the flow of water between roots and leaves – and growing new leaves and water transport cells when the warm spring returns.
Other plants, pine trees for example, protect themselves by narrowing their water transport cells, which makes it easier for cells to travel among air bubbles.
The third strategy is also the most extreme – some plants die on the ground in winter and start growing as new plants from seeds when conditions get warmer.
However, the study also found that these smart strategies were developed very slowly – over millions of years of evolution. This leads scientists to worry that plants may not be able to deal with human-caused climate change, which has only started occurring over the past few decades.
Scientists are hoping that this study can help people find possible ways to save plants from the threat of climate change.
【小题1】What is the article mainly about?
A.Why plants are not afraid of the winter chill. |
B.The ways that plants survive cold weather. |
C.Changes in plants’ water transport system in winter. |
D.How plants evolve to keep up with climate change. |
A.it produces more living tissues to stay alive |
B.its leaves quickly fall out and its roots begin to die |
C.lots of air bubbles form in its water transport system |
D.its water transport system could be blocked in the spring |
A.By dropping their leaves before winter. |
B.By narrowing their water transport cells. |
C.By widening their water transport cells. |
D.By leaving only the seeds alive and growing from the seeds in the spring. |
A.Plants may not be able to adapt to the increasingly cold climate. |
B.Human activities might have a great impact on the pace of plants’ evolution. |
C.Plants may not be able to evolve fast enough to adapt to human-caused climate change. |
D.The strategies plants develop are not good enough to protect them against cold. |
【小题1】B
【小题2】D
【小题3】A
【小题4】C
解析试题分析:在寒冷的冬天,人们有各种各样保暖的方法,但是植物怎么过冬呢?这篇文章讲的是植物在寒冷的天气生存的方法。
【小题1】主旨题:从全篇文章和第二段的句子:But things are not as easy for plants. Unlike humans, plants can’t move to escape the cold or generate heat to keep themselves warm. So how do they manage to survive the freezing winter?可知这篇文章讲的是植物在寒冷的天气生存的方法,选B。
【小题2】细节题:从第四段的句子;“If enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant,” 可知如果植物在冬天被冻住了,会影响它们的水运输系统在春天就会被堵塞,所以选D。
【小题3】细节题:从第五段的句子:Some plants, such as oak trees, avoid freezing damage by dropping their leaves before the winter chill sets in – effectively shutting off the flow of water between roots and leaves 可知橡树是通过在冬天将树叶落下,这样来在冬天幸存的,选A。
【小题4】细节题:根据文章倒数第二段的句子:This leads scientists to worry that plants may not be able to deal with human-caused climate change, which has only started occurring over the past few decades.可知科学家担心的是植物可能不能进化的那么快来适应人类造成的气候变化。C
考点:考查科普类短文
科目:高中英语 来源: 题型:阅读理解
What do you use to get around town? A car? A bike? Your feet ? perhaps you should try a segway!
The Segway is perfect for short journeys. It’s an electric vehicle that consists of a platform between two wheels, with a pole that connects the platform to the handlebars. To ride it , you step up onto the platform, and control the Segway by moving your body. Lean forwards to go faster, and back-wards to slow down.
On older models, direction was controlled by a twist grip(扭转把手)on the left handlebar. This varies the speeds between the two motors, and a decrease in the speed of the left wheel would turn the Segway to the left . With newer models you simply lean to the left or right. Meanwhile, a gyroscope (陀螺仪)detects your movements and prevents the machine from falling over. The Segway has a maximum speed of 19 km per hour and a range of about 38 km. after that, you need to plug it and recharge the battery.
Segways are used for a variety of purposes. People with mobility problems can now enjoy walks in the country with their friends and family. Some golfers see them as an alternative to the golf cart . And dog owners now have an easier way to take the dog to the park. A few police forces use Segways, too. They allow officers to move quickly while maintaining contact with the public. They’re also becoming a common sight on airport . However, the most popular use is in tourism , particularly for city tours . Visit any major tourist city in summer, sit outside a cafe for a while and there’s a good chance you’ll see a group of tourists passing on Segways.
【小题1】How do you turn to the left on a Segway of the new model?
A.Lean to the left | B.Adjust the twist grip |
C.Press the left bar | D.Control the gyroscope |
A.Less than 19 km | B.About 19 km |
C.About 38 km | D.Over 45 km |
A.families | B.golfers |
C.police | D.tourists |
A.Introduction→Ways of application→ structure→Principle of operation |
B.Introduction→ Principle of operation→Structure →Ways of application |
C.Introduction → Structure → Principle of operation →ways of application |
D.Structure→ Introduction→Principle of operation→Ways of application |
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科目:高中英语 来源: 题型:阅读理解
Growers around the world are using new methods to grow grapes to make wine. They use natural and organic methods to control harmful insects and weeds instead of using chemicals. Now, a winery in Canada has adopted a natural way to control its grapevines (葡萄藤). The Featherstone Winery is in southern Ontario. The grapevines, like other plants, need to be cut every year.
Cutting grapevines must be done very carefully. Only a targeted area of leaves is removed from the lower part of the vines to help the grapes grow better. But at the Featherstone Winery, no man or machine does the cutting. Instead, the job is done by 40 little wooly lambs.
David Johnson owns the vineyard (葡萄园). He says he learned about using lambs while visiting wineries in New Zealand. The young lambs are perfectly designed to do the job. They eat the grape leaves on the lower parts of the vine. But they are not tall enough to reach the grapes. They only weigh about 22 kilograms, so they do not beat down the soil. And their waste makes good organic fertilizer. In addition, using the lambs costs much less than hiring workers to cut the vines for seven weeks in summer. And when the cutting is done in August, the lambs become tasty dishes.
Mr. Johnson says he had a difficult time finding enough lambs to do the job. There are about 50 million lambs in New Zealand. But there are not nearly as many in Ontario. Also, some organic pesticides (杀虫剂) are harmful to lambs. And the lambs must be watched to make sure they do not eat too much of the grapevines.
David Johnson says the lambs help him carry out his environmental ideas about farming. They are lovely and peaceful and he likes having them in his vineyard. People visiting the vineyard also enjoy watching the lambs do their job.
【小题1】Farmers who grow grapes with natural and organic methods ________.
A.don't cut grapevines every year |
B.don't use chemicals to control harmful insects and weeds |
C.don't need to control harmful insects and weeds |
D.don't use organic fertilizer |
A.only have to remove the dead leaves |
B.need to remove a specific area of leaves |
C.shouldn't remove any part of the plants |
D.should let little lambs do the cutting |
A.the future of getting lambs to do the cutting |
B.the worries about using organic pesticides |
C.the ways to get lambs to do the cutting |
D.the problems related to lambs doing the cutting |
A.owns several wineries in Canada |
B.buys lambs from New Zealand |
C.is concerned about protecting the environment |
D.loves keeping lambs instead of farming |
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科目:高中英语 来源: 题型:阅读理解
Researchers have developed new software using smart phones’GPS and imaging abilities that determine the exact location of distant objects as well as monitor the speed and direction of moving objects.The software could eventually allow smart phone-armed soldiers to target the location of their enemies.On the home front,the software could be used by everyone,including golfers judging distance to the green and biologists documenting the location of a rare animal without disturbing it.
“The great advantage of a Smartphone is that it provides so many tools in a single,readily available,relatively inexpensive package,”said Qia Wang,a doctoral student who led the development of the software.“For example,on the battlefield,a soldier needs a rangefinder,compass,GPS and other tools to get information before calling in an air strike.With our software,the soldier can have all those instruments in one device that can be purchased off the shelf.When that soldier returns from War,she can use the same Software to protect her family by clocking a speeder near her children’s school and catching the criminal on video.”
Wang and his colleagues developed their software to locate and track:
Targets of known size—when the size of the target is known.a single image is enough to pinpoint the target’s location.
Targets of unknown size—If the exact size of a target is unknown,the software uses two images to triangulate the location of the target·
Moving targets—By taking a short video of a moving target,the smartphone software can calculate how fast the target is moving and in what direction it is going.
“Currently,our software is limited by the physical abilities of smartphone hardware,but the devices are improving rapidly,”Wang said.“We expect that improvements in GPS accuracy,battery life and camera resolution will allow our software to make even more accurate observations.”
【小题1】From Paragraph 1 we can know that the new software can.
A.determine the speed of moving objects |
B.1ocate objects in the distance exactly |
C.defend soldiers against their enemies |
D.help biologists protect rare animal |
A.make an advertisement |
B.describe the software briefly |
C.show the benefits of the software |
D.present the functions of smartphones |
A.By taking a short video. |
B.By locating its position. |
C.By taking a single image. |
D.By measuring real-life size. |
A.Casual. | B.Optimistic. | C.Cautious. | D.Flexible |
A.Qia Wang,a Talented Doctoral Student |
B.Use Smartphones to Their Full Potential |
C.Targeting and Tracking With Smartphones |
D.Smartphone-armed Soldiers on the Battlefield |
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科目:高中英语 来源: 题型:阅读理解
If you think English means endless new words, difficult grammar and sometimes strange pronunciation, you are wrong. Haven’t you noticed that you have become smarter since you started to learn a language?
According to a new study by a British university, learning a second language can lead to an increase in your brain power. Researchers found that learning other languages changes grey matter. This is the area of the brain which processes information. It is similar to the way that exercise builds muscles.
The study also found the earlier people learn a second language, the greater the effect is.
A team led by Dr. Andrea Mechelli, from University College London(UCL), took a group of Britons who only spoke English. They were compared with a group of“early bilinguals(通两种语言的人)”, who had learnt a second language before the age of five, as well as a number of later learners.
Scans showed that grey matter density in the brain was greater in bilinguals than in people without a second language. But the longer a person waited before mastering a new language, the smaller the difference was.
“Our findings suggest that the structure of the brain is changed by the experience of learning a second language,”said the scientists.
It means that the change itself increases the ability to learn.
Professor Dylan Vaughan Jones of the University of Wales, has researched the link between bilingualism and maths skills.
“Having two languages gives you two windows on the world and makes the brain more flexible,”he said,“You are actually going beyond language and have a better understanding of different ideas.”
The findings were matched in a study of native Italian speakers who had learned English as a second language between the ages of 2 and 34. Reading, writing and comprehension were all tested. The results showed that the earlier they started to learn, the better.“Studying a language means you get an entrance to another world,”explained the scientists.
【小题1】What does the underlined part“grey matter”(in paragraph 2) refer to?
A.Grey hair. | B.Material of the brain. |
C.Intelligence. | D.Difficult situations. |
A.change one’s brain completely |
B.improve one’s maths skills |
C.make one smarter than others |
D.increase the ability to learn |
A.the researchers from UCL did another study in Italy |
B.a similar study was done on native Italian speakers who learn English as a second language |
C.the research done on the Italians showed a totally different result |
D.it will be easier for one to travel around the world by learning a second language |
A.Learning a second language can help improve your brain power. |
B.You should learn a second language in English that is not your native language. |
C.If you want to learn a second language, you should do it at a certain age. |
D.The research done by the researchers from UCL is very successful. |
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科目:高中英语 来源: 题型:阅读理解
Many people think of the brain as a mystery. They don't know much about intelligence and how it works. When they do think about what intelligence is, many people believe that a person is born smart, average, or dumb — and stays that way in the whole life. But new research shows that the brain is more like a muscle — it changes and gets stronger when you use it. And scientists have been able to show just how the brain grows and gets stronger when you learn.
Everyone knows that when you lift weights, your muscles get bigger and you get stronger. A person who can't lift 20 pounds when he/she starts exercising can get strong enough to lift 100 pounds after working out for a long time. That's because the muscles become larger and stronger with exercise. And when you stop exercising, the muscles shrink and you get weaker. That's why people say “Use it or lose it!”
But most people don't know that when they practice and learn new things, parts of their brain change and get larger a lot like muscles do when they exercise. Inside the cortex (皮层) of the brain are billions of tiny nerve cells, called neurons. The nerve cells have branches connecting them to other cells in a complicated network. Communication between these brain cells is what allows us to think and solve problems. When you learn new things, these tiny connections in the brain actually multiply and get stronger. The more you challenge your mind to learn, the more your brain cells grow. Then, things that you once found very hard or even impossible to do — like speaking a foreign language or doing algebra (代数) — seem to become easy after learning them for a period of time. The result is a stronger, smarter brain.
Scientists started thinking that the human brain could develop and change when they studied animals' brains. They found out that animals that lived in a challenging environment were more “perspicacious” — they were better at solving problems and learning new things.
【小题1】According to the first paragraph,________.
A.the function of our brain is like that of the muscle |
B.until now it's impossible to explain the brain's mystery |
C.many people believe one's intelligence is naturally determined |
D.one's brain grows stronger as the age increases |
A.using the brain |
B.connecting things in your brain |
C.lifting weights |
D.doing research about the brain |
A.Strong. | B.Smart. | C.Popular. | D.Active. |
A.the differences between animals’ brains and humans’ brains |
B.the relation between human brains and muscles |
C.scientists’ findings about animals’ brains |
D.how to make your brain smarter through self-development |
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科目:高中英语 来源: 题型:阅读理解
Can noncombustion (非燃烧) technology create a no-pollution way to drive?Imagine pulling into a service station to fuel up your car. But not at the gas pump or electric battery charger —at the air pump! That’s not hot air, either! The next generation of cars may run on thin air. Wouldn’t that be an incredible way to cut both pollution and dependence on foreign oil?
If you’ve ever inflated a balloon and then let it go, you’ve got the basics to test-drive the amazing MiniCAT, currently being developed by Noteur Development International (MDI), headquartered in Luxembourg. Invented by Formula One racing car designer Guy Negre, this experimental vehicle is unlike any car you’ve ever seen. While your family’s traditional car or SUV draws its horsepower using combustion, the only fuel that MiniCAT needs (CAT stands for Compressed Air Technology) is the air we breathe.
Start with about 25,000 gallons of air. Now, press it all into a space smaller than your school locker—because that’s the size of two super-strong, high-pressure air tanks, made from fiber and fixed beneath the air car.
Confining that much air inside those small tanks generates an internal pressure of over 4,000 pounds per square inch. That’s over 300 times normal air pressure.
When this cold, high-pressure air enters MiniCAT’s unique engine, it interacts(交互作用) with warmer air to create pressure waves that pump the engine’s engineered pistons (活塞) to move the car. MiniCAT’s projected top speed is 60 miles per hour, with a range of 120 miles on a full air supply.
【小题1】What is the passage mainly about?
A.Ways to cut down air pollution. |
B.Cars that run on thin air. |
C.Formula One racing car designer. |
D.Dependence on foreign oil. |
A.The name of a car. |
B.The name of a balloon. |
C.The name of a car company. |
D.The name of a car designer. |
A.Keeping | B.Preventing | C.Pushing | D.Running |
A.How much pressure the air creates. |
B.How the car works. |
C.What the normal air pressure is. |
D.How the air gets into the engine. |
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科目:高中英语 来源: 题型:阅读理解
Some weightloss camps, which are rare in China just a few years ago,have multiplied in Beijing, Qingdao, Shenzhen,and other cities. Today about 15 percent of adults, or 200 million Chinese, are reportedly overweight.Of these, 90 million—about 7 percent—are obese(极肥胖的).
Experts say the obesity epidemic(流行病) is spreading to children, though more slowly than in adults. The obesity, they say, will do harm to the health of China’ s citizens and economy.“We're seeing a very large number of teenagers who are quite heavy and aren't moving much,” said Barry Popkin, a nutrition(营养) professor. Popkin carries out an ongoing healthandnutrition survey of 16,000 households in China. He says more kids today are overeating and putting on weight “quite quickly.” In just ten years China‘s childhood obesity rate has doubled,with the greatest gains coming in urban areas.“In big cities it's a big problem.”
Some experts blame the extra fat on a range of factors, many of them tied to China’ s rapidly changing economy and culture. The diets of Chinese adults and children are far higher in meats, fish, eggs, dairy products, fats and sugars than ever before. In addition,kids—especially city dwellers—are more sedentary today and spend more time indoors in front of homework, television,computer games, and the Internet.
Shuwen Ng,a health economist, says that kids in China now have pocket money, and they spend a portion of it on junk food. Ng adds that advertising and peer groups influence kids' food choices. Certain foods, such as new candies or fast food, have attractive features.
China’ s childhood obesity rate stillfall behind that of the United States, where some 15 percent of kids are said to be obese. But the longterm effects are equally serious.
【小题1】According to the passage we know________.
A.weightloss camps have been very popular in China six years ago |
B.about 290 million Chinese are overweight in China in all |
C.in China childhood obesity rate in rural areas is lower than that in major cities |
D.America’ s childhood obesity rate is lower than China’s |
A.Advertising on some new candies. |
B.ignorance of weight-control. |
C.Playing computer games for long time. |
D.Having pocket money. |
A.confident | B.patient | C.energetic | D.inactive |
A.obesity explosion in China will affect the United States |
B.there are great difference in kids' food choices now |
C.junk food leads to childhood obesity |
D.city children eat more than rural children |
A.Chinese Childhood Obesity problem |
B.Weightloss Camps in China |
C.Obesity problem's influence on Chinese Economy |
D.Obesity problem in China and America |
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科目:高中英语 来源: 题型:阅读理解
Global warming happens when greenhouse gases trap heat and light from the sun in the earth’s atmosphere, which increases the temperature. This is like when heat is trapped in a car. On a hot day, the car gets hotter when it is out in the parking lot. This is because the heat and light from the sun can get into the car, by going through the windows,but it can’t get back out. This is what the greenhouse effect does to the earth .The heat and light can get through the atmosphere, but it can’t get out As a result,the temperature rises.
Sometimes the temperature can change in a way that helps us. The greenhouse effect makes the earth appropriate for people to live on Without it,the earth would be freezing,or it would be burning hot. It would be freezing at night because we would not get the sun’s heat and light .During the day, especially during the summer, it would be burning because the sun would be up with no atmosphere to filter(过滤)it,so people,plants,and animals would be exposed to all the light and heat.
Although the greenhouse effect makes the earth able to have people living on it,if there gets to be too many gases,the each can get unusually warmer, and many plants,animals.and people will die. Plants would die because they would not be able to take the heat .This would cause us to have less food to eat, and it would also limit the food that animals have. With less food for the animals that we need to survive we would even have less food. Gradually, people,plants,and animals would all die of hunger.
People are doing many things to try to stop global warming .One thing is carpooling—driving with someone to a place that you are both going to. Another thing is being more careful about leaving electrical devices turned on. Now, more people are even riding buses or bikes to lower the amount of greenhouse gases in the air .Although adults do many things to help stop global warming, kids call do just as much.
【小题1】By the example given in Paragraph l, the author wants to__________.
A.explain how global warming happens |
B.show his feeling in a car in hot summer |
C.tell us cars are causes of greenhouse gases |
D.say that I there are greenhouse gases in every car |
A.light | B.greenhouse effect | C.temperature | D.heat |
A.IT only traps the heat of the sun. |
B.It does great harm to humans. |
C.It makes the earth neither to hot nor too cold. |
D.It prevents all the light from the sun shining on the earth. |
A.lf there is greenhouse effect.all the plants will die |
B.Human beings are likely to disappear from the earth |
C.Crops can ′t take in the heat lf there is greenhouse effect |
D.Although greenhouse effect is necessary.Too much of it will cause us to die. |
A.What kids can do to help stop global warming. |
B.Who should be responsible for the environmental problems. |
C.What global warming is doing to the environment. |
D.Why cars and buses pollute the air a lot |
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