How would you like to sleep with one half your brain asleep and the other half a
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How would you like to sleep with one half your brain asleep and the other half awake? Dolphins sleep this way. Recently, scientists at Indiana State University have discovered that ducks sleep this way too. They found that ducks sleep half awake so they can rest and watch for danger at the same time.
After putting their ducks in a row and videotaping them, some researchers found ducks on the end of each row spent more time asleep with one eye open, apparently looking for predators.
“The more the ducks felt threatened, the more they slept with one eye open,” said lead author Niels C. Rattenborg, a graduate student at Indiana State University, Terre Haute. “The unique aspect is not that they do it, but that they control it. When they sleep at the edge of a group, they tend to realize greater danger, so they spend more time sleeping with one half of their brain.” Ducks with one eye open were still awake enough to detect predators, said the authors of the study, which appears today in the journal Nature.
The researchers studied four groups of four ducks held in plastic boxes, which were arranged in a row. Ducks on the end were found to sleep with one eye open 31.8 per cent of the time, compared to 12.4 percent of the time for ducks in the central position.
Also, ducks in the central position did not open one eye more than the others, while ducks on each end kept the eye facing away from the group open 86.2 per cent of the time. Brain wave readings of the ducks showed that the half of the brain receiving signals from the closed eye indicated that half of the brain was sleeping. Signals from the half of the brain receiving signals from the open eye showed a state between fully awake and asleep.
小题1:The under lined word “predator” is most likely to mean .| A．an animal that is likely to be friends with ducks | | B．a human being who looks after and feeds ducks | | C．a scientist who does research work on animals | | D．an animal that hunts, kills and eats other animals |
小题2:Ducks at the end of each row sleep with one eye open because .| A．they are looking for food | | B．they are watching out for danger | | C．they want to enjoy the scenery | | D．they are unique in their sleeping habit |
小题3:Which of the following is true according to the passage?| A．Ducks with one eye open at the edge can still enjoy a certain degree of sleep. | | B．Ducks with less sense of duty usually choose to stay in the center of a row. | | C．Ducks on the northern end of a row would keep their eye facing the south open. | | D．A video tape recorder was the only electronic device used in the experiment. |
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答案
小题1:D
小题2:B
小题3:A |
解析
试题分析：文章介绍了海豚和鸭子在休息的时候有一半大脑是清醒的，一半是休息的，在休息时有一只眼睛也是不断睁开的，研究者们也做了一系列的实验来证明他们是这么做的，并且了解了这么做的原因，主要是为了防止可能会出现的危险。
小题1: D细节理解题。They found that ducks sleep half awake so they can rest and watch for danger at the same time. 研究员们发现，鸭子在休息时一半是清醒的，因此他们能够同时注意危险；The more the ducks felt threatened, the more they slept with one eye open鸭子越感觉危险，他们睡觉时一只眼睛睁得越多。由此可知他们睡觉睁一只眼睛是为了寻找可能出现的危险。故答案应为D。
小题2:B细节理解题。some researchers found ducks on the end of each row spent more time asleep with one eye open, apparently looking for predators.句意为：一些研究员发现，在每队边上的鸭子花费更多的时间睁着眼睛睡觉，很明显他是是警惕危险；When they sleep at the edge of a group, they tend to realize greater danger, so they spend more time sleeping with one half of their brain.当他们在边的时候，他们往往会意识到更大的危险，因此他们花费更多的时间保持他们大脑的清醒。故答案应为B。
小题3:A细节判断题。文章第一自然段说明鸭子和海豚睡觉时大脑一半是清醒的一半是休息的，因此在边上的鸭子也有一定程度的休息是正解的。Ducks with less sense of duty usually choose to stay in the center of a row.没有责任感的鸭子通常选择在一排的中间，文章里没有说明鸭子是选地方休息的；Ducks on the northern end of a row would keep their eye facing the south open文中没有提到哪个方向的鸭子面朝向哪个方向；A video tape recorder was the only electronic device used in the experiment.文中提到了这个设备，但没说明是唯一的，故答案A是正确的。
【考点】考查科普环保类文章的阅读理解。 |
举一反三
Half of the world’s population is affected by Asian monsoons（季风）, but monsoons are difficult to predict. American researchers have put together a 700-year record of the rainy seasons, which is expected to provide guidance for experts making weather predictions.
Every year, damp air masses，known as monsoon，produce large amounts of rainfall in India, East Asia, Northern Australia and East Africa. All this wet air is pulled in by a high pressure area over the Indian Ocean and a low pressure area to the south.
According to Edward Cook , a weather expert at Columbia University in New York., the complex nature of the climate systems across Asia makes monsoons hard to predict. In addition, climate records for the area are too recent and not detailed enough to be of much use. Therefore, he and a team of researchers spent more than fifteen years traveling across Asia, looking for trees old enough to provide long-term records. They measured the rings, or circles, inside thousands of ancient trees in more than 300 places.
Rainfall has a direct link to the growth and width of rings on some kinds of trees. The researchers developed a document they are calling a Monsoon Asia Drought Atlas. It shows the effect of monsoons over seven centuries, beginning in the 1300s.
Professor Cook says the tree-ring records show periods of wet and dry weather. “If the monsoon basically fails or is a very weak one, the trees affected by monsoons at that location might put on a very narrow ring. But if the monsoon is very strong, the trees affected by that monsoon might put on a wide ring for that year. So, the wide and narrow ring widths of the chronology that we developed in Asia provide us with a measure of monsoon variability.” With all this information, researchers say they can begin to improve computer climate models for predicting the behavior of monsoons.
“There has been widespread famine and starvation and human dying in the past in large droughts. And on the other hand, if the monsoon is particularly heavy, it can cause extensive flooding.” said Eugene Wahl, a scientist with America’s National Oceanic and Atmospheric Administration. “So, to get a sense of what the regional moisture patterns have been, dryness and wetness over such a long period of time in great detail, I would call it a kind of victory for climate science.”
小题1:What’s the passage mainly about？| A．The effects of Asian monsoons. | | B．The necessity of weather forecast. | | C．The achievements of Edward cook. | | D．A breakthrough in monsoon prediction. |
小题2:It is difficult for experts to predict Asian monsoons because _______.| A．it is hard to keep long-term climate records. | | B．they are formed under complex climate systems. | | C．they influence many nations. | | D．there is heavy rainfall in Asia. |
小题3:What can be inferred from the passage?| A．Long and detailed climate records can offer useful information for monsoon research. | | B．The Monsoon Asia Drought Atlas has a monsoon record for about 1,300 years. | | C．The trees affected by monsoon grow fast if the monsoon is weak. | | D．The rainfall might be low although the monsoon is strong in monsoon-affected areas. |
小题4:According to Professor Cook, the rings of the trees _______.| A．determine the regional climate. | | B．have a great influence on the regional climate. | | C．offer people information about the regional climate. | | D．reflect all kinds of regional climate information. |
小题5:Which of the following best describes the tone of this passage?| A．Matter-of –fact | B．Pessimistic | C．Humorous | D．Friendly. |
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This site , all-birds. com, is about bird watching. Enjoy your browsing. There is much to learn and see.
Bird Watching Equipment
Some items that might make bird watching more enjoyable are binoculars （ 双目望远镜） , a camera, some kind of system for keeping notes, and maybe a back pack． Birders often keep lists of the birds they see along with notes about the habits． There is some great bird log software that will let you keep records on your computer． For more details on choosing binoculars see our Binocular -Optics page．
Clothes
If you are walking through a wooded area just wear clothes you would wear on any hike or field trip． You are best off wearing clothes with dull colors that mix into the background． Greens, browns, and grays are good． Avoid fabrics that rustle（沙沙响）easily． Depending on the birds you are watching you may want to get rain gear, rubber boots and warm clothing． For birds such as owls that you might look for in the evening a strong flashlight is also handy．
Choosing a Bird Field Guide
Take a good field guide to identify birds． Look for clear color pictures that make it easy to recognize one bird from another． Next to each picture should be detailed descriptions of each bird"s anatomy, habits, and what it eats． The guide should have information about what habitat each species uses． Many guides have maps showing the range of different birds along with their migration patterns．
Where and When to see Birds
Learning the habitats of birds in your area will increase the number of birds you see, and make your birding more enjoyable． If you know that Meadow larks are likely to be in open grassy areas, and dippers are forage along stream beds, you may be looking for them if you are in those types of habitats． Edge areas where different types of habitats meet will likely have more species in them． You are more likely to see specific birds at certain times of the day． For example songbirds are easier to see two to three hours after dawn, or just before sunset． This is when songbirds are most actively feeding． Many small birds will be silent or even hidden during the rest of the day． After sunup is the best time to see eagles and hawks． Visibility is best for hunting at this time, and they can soar on the thermal currents from the warmed air． Birds like owls are more likely to be seen in the evening． Many shorebirds and waders rest at high tide and feed when the water rises or falls．
Photographing Birds
Patience in Bird Photography
Most birds are afraid of people, and all species have their own comfort zone． With a little time you can learn the comfort zone of the birds you are photographing． Once they know that you are not a threat you may be able to get closer．
Type or Style
Your reason for photographing birds may determine your style and the kind of equipment you use． If you are just recording the kinds of birds you see you don"t need to get as close, and you can use less expensive equipment, then you need for high quality prints.
Photographing Birds in Flight
Photographing birds in flight can be fun． Many digital cameras have a tracking function． With these you focus on the bird, and then as you track it the lens will keep focus．
Use Your Yard
Choose an open area where the birds will get direct sunlight, showing off their magnificent colors．
Try using props
Birds will often land on a stick or post near a seed feeder before going to the feeder． The background was just an out of focus fence but you can use anything you want for a background, and then wait for a bird to perch.
小题1:The main purpose of the passage is to _____.| A．attract more people to photograph birds | | B．help birders learn how to identify and understand birds | | C．call on people to set some comfort zones for birds | | D．inform birders of the results of a scientific research on birds |
小题2:Clothes in ______ are highly recommended when you are going bird watching．| A．red | B．yellow | C．brown | D．blue |
小题3:________ are likely to be seen at 7 in the morning．| A．Owls | B．Shorebirds | C．Songbirds | D．Larks |
小题4:Which of the following statement is TRUE according to the passage?| A．A stick in the yard may scares birds off when you are photographing them． | | B．It will be wise for birders to hire a guide for themselves． | | C．Birders have to bring some notebooks to keep records of birds" habits． | | D．A flashlight will come in handy when you look for owls． |
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What if we could replace oil with a fuel which produced no pollution and which everybody had equal access to? The good news is that we can. In fact, we are swimming in it--- literally.
Hydrogen is one of the building blocks of the universe. Our own sun is basically a big, dense cloud of the stuff. And hydrogen can be used to create electricity for power, heat and light.
The problem is that hydrogen is everywhere and nowhere at the same time. It does not exist as a material on its own, but is always part of something else. So it has to be separated before it can be used.
Most commercial hydrogen in use now is created from natural gas. As oil will start to run out in around the year 2030, it makes sense to produce as much hydrogen as possible as soon as we can. But natural gas supplies will also begin to run out soon after. Another source is needed.
Researchers are now using electricity to make water into hydrogen. Companies are working on the problem in their own areas. The first commercial hydrogen “fuel cells” for computers and mobile phones have already come on to the market. Auto companies have also invested over US $2 billion in the production of hydrogen fuelled cars.
The nations of a hydrogen fuelled planet would not fight over energy recourses. There would be a great reduction in pollution. The only by-product of creating hydrogen is pure drinking water--- something that is very scarce in many parts of the world. But that is not where the good news ends. Once the costs of producing hydrogen have been brought down, it will possibly provide power for a third of the Earth’s population that has no electricity.
And electricity creates wealth. In South Africa over the last decade there has been a large programme of electrification. Thanks to the programme, people do not have to spend their days looking firewood to burn for heat. And with electric light, they can work long into the night.
Some scientists see radical changes in the way the human race co-operates. Hydrogen creates electricity, and is also created by it. With dual use fuel cells, everyone who consumes energy could also produce it. Late at night, a man drives home in London and connects his car into the “world-wide hydrogen web,” which it supplies with electricity. A few hours later, a man in Beijing uses that electricity to power the hydrogen cell in his car. Hydrogen could be the first democratic energy source.
Like all dreams of the future, it seems very far away. But the threat of war and terrorism in the Middle East has made governments and businesses more aware of the need to end oil dependency and spend more time and money on hydrogen resource. So maybe the threat of war is not a completely bad thing for the future of the human race.
小题1:What does the underlined word “it” in the last but one paragraph refer to? | A．wealth | B．hydrogen | C．electricity | D．fuel |
小题2:What is the problem with using hydrogen as energy?| A．It has by-products. | | B．It has to be separated from other materials. | | C．It will make energy too cheap. | | D．It is too far away from us. |
小题3:Why does the author give the example in the last but one paragraph ?| A．To tell us that we produce energy while using hydrogen power. | | B．To tell us that hydrogen power does not produce pollution. | | C．To show hydrogen power can stop war. | | D．To show hydrogen power is cheap. |
小题4:What is the author’s attitude about the future?| A．skeptical | B．negative | C．indifferent | D．positive |
小题5:What is the passage mainly about?| A．war and energy | B．the future of hydrogen as an energy resource | | C．the disadvantages of oil | D．How to end war |
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The UK has a well-respected higher education system and some of the top universities and research institutions in the world. But to those who are new to it all, sometimes it can be confusing.
October is usually the busiest month in the college calendar. Universities have something called Freshers’ Week for their newcomers. It’s a great opportunity to make new friends, join lots of clubs and settle into university life.
However, having just left the comfort of home and all your friends behind, the prospect (前景) of meeting lots of strangers in big halls can be nerve-wracking (令人焦虑不安的). Where do you start? Who should you make friends with? Which clubs should you join?
Luckily, there will be thousands of others in the same boat as you worrying about starting their university social life on the right foot. So just take it all in slowly. Don’t rush into anything that you’ll regret for the next three years.
Here are some top advice from past students on how to survive Freshers’ Week：
● Learn rules. Make sure you know British social etiquette (礼节). Have a few wine glasses and snacks handy for your housemates and friends.
● Be kind. Sometimes cups of tea or even slices of toast can give you a head start in making friends.
● Be sociable. The more active you are, the more likely you’ll be to meet new people than if you’re someone who never leaves his room.
● Bring a doorstop. Keep your door open when you’re in and that sends positive messages to your neighbors that you’re friendly.
So with a bit of clever planning and effort, Freshers’ Week can give you a great start to your university life and soon you’ll be passing on your experience to next year’s freshers.
小题1:We can learn from the passage that ______.| A．Freshers’ Week usually comes in September in UK | | B．all the students are required to join certain clubs in UK | | C．many freshers are worried about how to fit university life | | D．most of the students in the UK spend three years in universities |
小题2:Why does the author suggest having wine glasses and snacks handy?| A．To pass the busy university life. | | B．To help make friends with other freshers. | | C．To show yourself a drinker as others. | | D．To enjoy the time in a happy way. |
小题3:The main purpose of the passage is to _______.| A．tell the newcomers how to make a new start in universities | | B．introduce something about higher education system of the UK | | C．inform the freshers of British social etiquette | | D．advise the freshmen how to behave well in the beginning |
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One of my China Dialogue colleagues in Beijing recently bought a Philips energy-saving light bulb to replace a standard one．He was happy with his choice．It may have cost 30 yuan （just under US$4．50） - ten times the price of a filament （灯丝） bulb - but he wanted to save energy as part of his low-carbon lifestyle．And according to the shopkeeper, he would save, in the long run, much more than the 30 yuan he was spending．
Yet only one month later, his expensive light bulb blew up, before he had saved even a small part of the purchase price．Will he stick to his high-cost, low-carbon lifestyle?
China"s environmental organizations have started to advocate low-carbon lifestyles and the decrease of carbon footprints to help fight against climate change．But they have overlooked one fact: in China, low-carbon living comes at a high cost．It means buying energy-saving bulbs and appliances, and environmentally friendly building materials and daily goods．Cost can no longer be the only standard for purchases．An energy-saving and environmentally friendly product is more expensive than a standard alternative - whether it"s a simple light bulb or the house it shines．For average consumers, even buying an ordinary bulb is a huge burden．How can we persuade ordinary people to choose an energy-saving residence? This is not a trend they can afford to follow; perhaps this fashion is only for the rich．
Most consumers today do not cause huge carbon dioxide （CO2） emissions．Their responsibility lies not in choosing a low-carbon lifestyle today, but in avoiding a high-carbon life in the future．The principle of "common but differentiated responsibility" - a basis of sustainable development - can be applied here as well．
In China, low-carbon living still is resisted by a lack of social infrastructure（基础设施）. Even if your salary allows you to make that choice, nobody is there to help you accomplish it．
Consider energy-saving homes. You need to find out whether or not the developer has used natural materials wherever possible; how effective the insulation（绝缘物、隔热物） is; and what the green credentials of installed equipment are．You can read up a little, but you"ll still be lucky to avoid being puzzled by the developers" marketing．Many so-called energy-saving buildings are nothing of the sort, and some are even more energy-hungry than the average home - as Li Taige warned in his article "Energy-efficient buildings? Not always", on China Dialogue last August．
小题1: What may probably be the best title of this passage?| A．To purchase a cheap bulb - your wise alternative． | | B．To choose an energy-saving residence - a must of your life | | C．To learn a low-carbon lifestyle - each citizen"s responsibility | | D．To learn a low-carbon lifestyle - a promising but difficult purpose |
小题2:Why does the writer say this fashion is only for the rich in the fourth paragraph?| A．Because the cost is a very important standard for purchases. | | B．Because buying an ordinary bulb is very expensive. | | C．Because energy-saving products are more expensive than the common alternatives. | | D．Because rich people like to follow this trend. |
小题3: What does the writer think of energy-saving homes?| A．Most of them are environmentally friendly. | | B．They are musts of low-carbon lifestyle of Chinese. | | C．They are huge burdens for Chinese people. | | D．Many of them are more in name than in reality. |
小题4:We can infer from the passage that ____．| A．Using energy-saving bulbs and appliances is a fashion． | | B．It"s easy for most Chinese to try to learn a low-carbon lifestyle． | | C．All citizens in China don’t have the same responsibility in living a low-carbon lifestyle． | | D．Most Chinese families cannot afford to purchase an energy-saving residence. |
小题5:What is the writer"s attitude towards the low-carbon lifestyle?| A．informative and entertaining | B．supportive but cautious | | C．negative but wise | D．positive and active |
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