Birds that are half-asleep — with one brain hemisphere (半球) alert(警觉) and the other sleeping — control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have recorded half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze(注视) direction.
Also, birds napping (打盹) at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in inner spots, outer birds half-asleep during some 32 percent of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep developed over time as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
1.According to the passage, birds often half sleep because ______.
A. they have to watch out for possible attacks
B. their brain hemispheres take turns to rest
C. the two halves of their brain are differently organized
D. they have to constantly keep an eye on their companions
2.What is implied about the example of a bird’s sleeping in front of a mirror?
A. An imagined companion gives the bird a sense of security.
B. Birds prefer to sleep in pairs for the sake of their security.
C. The phenomenon of birds napping in pairs is widespread.
D. A single pet bird enjoys seeing its own reflection in the mirror.
3.It can be inferred that _______.
A. Birds never sleep with both hemispheres resting at once.
B. Inner ducks depend on single-hemisphere sleep, rather than total relaxation, as often as birds napping at the end of the line do
C. It is not the first time for scientists to research on birds’ half-brain sleep
D. Birds hardly sleep without a companion
4.By saying “just the tip of the iceberg”, Siegel suggests that _______.
A. half-brain sleep has something to do with icy weather
B. the mystery of half-brain sleep is close to being solved
C. most birds living in cold regions tend to be half sleepers
D. half-brain sleep may exist among other species
高二英语阅读理解困难题
Birds that are half-asleep — with one brain hemisphere (半球) alert(警觉) and the other sleeping — control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have recorded half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze(注视) direction.
Also, birds napping (打盹) at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in inner spots, outer birds half-asleep during some 32 percent of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep developed over time as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
1.According to the passage, birds often half sleep because ______.
A. they have to watch out for possible attacks
B. their brain hemispheres take turns to rest
C. the two halves of their brain are differently organized
D. they have to constantly keep an eye on their companions
2.What is implied about the example of a bird’s sleeping in front of a mirror?
A. An imagined companion gives the bird a sense of security.
B. Birds prefer to sleep in pairs for the sake of their security.
C. The phenomenon of birds napping in pairs is widespread.
D. A single pet bird enjoys seeing its own reflection in the mirror.
3.It can be inferred that _______.
A. Birds never sleep with both hemispheres resting at once.
B. Inner ducks depend on single-hemisphere sleep, rather than total relaxation, as often as birds napping at the end of the line do
C. It is not the first time for scientists to research on birds’ half-brain sleep
D. Birds hardly sleep without a companion
4.By saying “just the tip of the iceberg”, Siegel suggests that _______.
A. half-brain sleep has something to do with icy weather
B. the mystery of half-brain sleep is close to being solved
C. most birds living in cold regions tend to be half sleepers
D. half-brain sleep may exist among other species
高二英语阅读理解困难题查看答案及解析
Birds that are half-asleep—with one brain hemisphere (半球) alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have documented half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze direction.
Also, birds napping at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12% for birds in inner spots, outer birds half sleep during some 32% of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep evolved when creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side by side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights(理解) into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
1.According to the passage, birds often half sleep because _________________________.
A. they have to watch out for possible attacks
B. their brain hemispheres take turns to rest
C. the two halves of their brain are differently structured
D. they have to constantly keep an eye on their companions
2.What does the underlined word “evolved” mean in paragraph 6?
A. developed B. changed
C. disappeared D. helped
3.What is implied about the example of a bird's sleeping in front of a mirror?
A. Birds prefer to sleep in pairs for the sake of their security.
B. An imagined companion gives the bird a sense of security.
C. The phenomenon of birds napping in pairs is widespread.
D. A single pet bird enjoys seeing its own reflection in the mirror.
4.While sleeping, some water animals tend to keep half awake in order to _________________.
A. alert themselves to the approaching enemy
B. surface from water now and then to breathe
C. be sensitive to the ever-changing environment
D. avoid being swept away by rapid currents
5.It can be inferred that _______________________.
A. birds never sleep with both hemispheres resting at once.
B. inner ducks depend on single-hemisphere sleep, rather than total relaxation, as often as birds napping at the end of the line do.
C. it is not the first time for scientists to research on birds’ half-brain sleep
D. birds hardly sleep without a companion
6. By saying “just the tip of the iceberg”, Siegel suggests that _________________________.
A. half-brain sleep has something to do with icy weather
B. the mystery of half-brain sleep is close to being solved
C. most birds living in cold regions tend to be half sleepers
D. half-brain sleep may exist among other species
高二英语阅读理解中等难度题查看答案及解析
These are some signs that you can see on the roads of Great Britain.
Number one is a sign with the number thirty on it. When drivers see this sign they must not go at more than thirty miles an hour. We see this sign when we get to parts of the country where there are many houses and other buildings, for example, when we are getting near a town. Thirty miles an hour is the speed limit. Number two is sign for the end of the speed limit. We are out of the town now and may go at more than thirty miles an hour. Number three is a sign that we are near a crossroads, that is, a place where two roads cross. We must drive carefully. Number four is a sign that there is a bend in the road. Again, we must drive slowly and carefully. Number five is a sign that there is a hill and number six is a sign that the roads get narrow. Drivers must go slowly and carefully. Number seven has the word “school” on it. This is a sign that there is a school at the side of a street or road. Perhaps there are children going to school or leaving school. So drivers must look carefully and go slowly until they are past the school building.
Number eight is a sign with the letter P on it. The letter P is for “parking.” A parking place is a place where drivers may leave their cars. If the driver of a car wants to leave his car and go to the shops, he looks for this sign. Then he knows that he may leave his or her car there.
1.Who will most probably read the passage?
A. People who drive badly. B. People who are learning to drive.
C. People who drive well. D. People who drive carelessly.
2.When a driver sees the sign number one, he must .
A. always go at 30 miles an hour
B. go at more that 30 miles an hour
C. not go at more than 30 miles an hour
D. stop
3.A driver must drive carefully when he gets to .
A. a bend B. a crossroads
C. a narrow road D. all of them
4.If a driver wants to leaves his car and go to the shops, .
A. he can leave his car anywhere
B. he can leave his car at the gate of any shop
C. he must look for the sign with the letter P on it
D. he can leave his car at the side of the street.
5.Now , you—three drivers are driving side by side along the road, if you see the No. six sign, you have to _______.
A. drive along one after one because the road is not wide enough
B. drive more slowly because of the speed limit
C. drive more carefully because school children may cross the road
D. drive slowly because you have got to drive uphill
高二英语阅读理解中等难度题查看答案及解析
Compared with the price of that store,the price of this one sounds________—all the goods are good value.
A.considerable B.reasonable
C.available D.sensible
高二英语单项填空中等难度题查看答案及解析
We are advised to work with more than one program ______ we have to use them at work.
A. so that B. in case C. now that D. even though
高二英语单项填空中等难度题查看答案及解析
Did you know that women’s brains are smaller than men’s? The average women’s brain weighs 10% less than men’s. Since research has shown that the bigger the brain, the cleverer the animal, men must be more intelligent than women. Right? Wrong. Men and women always score similarly on intelligence tests, despite the difference in brain size. Why? After years of study, researchers have concluded that it’s what’s inside that matters, not just the size of the brain. The brain consists of “grey matter” .
It has been suggested that smaller brain appears to work faster, perhaps because the two sides of the brain are better connected in women. This means that little girls tend to learn to speak earlier, and that women can understand sorts of information from different sources at the same time. When it comes to talking to the boss on the phone, cooking dinner and keeping an eye on the baby all at the same time, it’s women who come out on top every time.
There are other important differences between two sexes. As white matter is the key to spatial(空间的) tasks, men know better where things are in relation to other things. “A great footballer always knows where he is in relation to the other players, and he knows where to go,” says one researcher. That may explain one of life’s great mysteries: why men refuse to ask for directions … and women often need to!
The differences begin when fetuses(胎儿) are about nine weeks old, which can be seen in the action of children and young as one. A boy would try to climb a barrier (障碍物) before him or push it down while a girl would attract help from others. These brain differences also explain the fact that more men take up jobs that require good spatial skills, while more women speech skills. It may all go back to our ancestors(祖先) ,among whom women needed speech skills to take care of their babies and men needed spatial skills to hunt, according to one research.
If all this disappoints you, it shouldn’t. “The brain changes throughout our lives according to what we do with it.” says a biologist.
1.Which of the following is true according to the first paragraph?
A. Women’s brain is 10% less than men’s.
B. Grey matter plays the same role as white matter.
C. Grey matter controls thinking in the brain.
D. Both sexes have the same amount of white matter.
2.What can we infer from the second and third paragraphs?
A. Women prefer doing many things at a time.
B. Men do better dealing with one job at a time.
C. Women do not need to tell directions.
D. Men have weaker spatial abilities.
3.Which of the following do you agree with according to the fourth paragraph?
A. Young boys may be stronger than young girls.
B. More women take up jobs requiring speech skills
C. Women may have stronger feelings than men.
D. Our ancestors needed more spatial skills.
4.What is the writer’s attitude in writing this passage?
A. Defensive. B. Persuasive.
C. Supportive. D. Objective.
高二英语阅读理解中等难度题查看答案及解析
Do you know that women’s brains are smaller than men’s? The average women’s brain weighs 10% less than men’s. Since researches have shown that the bigger the brain, the cleverer the animal, men must be more intelligent than women. Right? Wrong. Men and women always score similarly on intelligence tests, despite the difference in brain size. Why? After years of study, researchers have concluded that it’s what’s inside that matters, not just the size of the brain. The brain consists of “grey matter” and “white matter”. While men have more of the latter, the amount of “thinking” brain is almost exactly the same in both sexes.
It has been suggested that smaller brain appears to work faster, perhaps because the two sides of the brain are better connected in women. This means that little girls tend to learn to speak earlier, and that women can understand sorts of information from different sources at the same time. When it comes to talking to the boss on the phone, cooking dinner and keeping an eye on the baby all at the same time, it’s women who come out on top every time.
There are other important differences between two sexes. As white matter is the key to spatial(空间的) tasks, men know better where things are in relation to other things. “A great footballer always knows where he is in relation to the other players, and he knows where to go,” says one researcher. That may explain one of life’s great mysteries—why men refuse to ask for directions … and women often need to!
The differences begin when fetuses(胎儿) are about nine weeks old, which can be seen in the action of children as young as one. A boy would try to climb a barrier (障碍物) before him or push it down while a girl would attract help from others. These brain differences also explain the fact that more men take up jobs that require good spatial skills, while more women speech skills. It may all go back to our ancestors, among whom women needed speech skills to take care of their babies and men needed spatial skills to hunt, according to one research.
If all this disappoints you, it shouldn’t. “The brain changes throughout our lives according to what we do with it.” says a biologist.
1.Which of the following is true according to the first paragraph?
A. Women’s brain is 10% less than men’s
B. Grey matter plays the same role as white matter.
C. Grey matter controls thinking in the brain.
D. Both sexes have the same amount of white matter.
2.What can we infer from the second and third paragraphs?
A. Women prefer doing many things at a time.
B. Men do better dealing with one job at a time.
C. Women do not need to tell directions.
D. Men have weaker spatial abilities.
3. Which of the following do you agree with according to the fourth paragraph?
A. Young boys may be stronger than young girls.
B. More women take up jobs requiring speech skills.
C. Women may have stronger feelings than men.
D. Our ancestors needed more spatial skills.
4.What is the writer’s attitude in writing this passage?
A. Defensive. B. Persuasive.
C. Supportive. D. Objective.
高二英语阅读理解中等难度题查看答案及解析
Did you know that women’s brains are smaller than men’s? The average women’s brain weighs 10% less than men’s.Since research has shown that the bigger the brain, the cleverer the animal, men must be more intelligent than women.Right? Wrong.Men and women always score similarly on intelligence tests, despite the difference in brain size.Why? After years of study, researchers have concluded that it’s what’s inside that matters, not just the size of the brain.The brain consists of “grey matter” and “white matter”.While men have more of the latter, the amount of “thinking” brain is almost exactly the same in both sexes.
It has been suggested that smaller brain appears to work faster, perhaps because the two sides of the brain are better connected in women.This means that little girls tend to learn to speak earlier, and that women can understand sorts of information from different sources at the same time.When it comes to talking to the boss on the phone, cooking dinner and keeping an eye on the baby all at the same time, it’s women who come out on top every time.
There are other important differences between two sexes.As white matter is the key to spatial tasks, men know better where things are in relation to other things.“A great footballer always knows where he is in relation to the other players, and he knows where to go,” says one researcher.That may explain one of life’s great mysteries: why men refuse to ask for direction and women often need to!
The differences begin when fetuses(胎儿)are about nine weeks old, which can be seen in the action of children as young as one.A boy would try to climb a barrier before him or push it down while a girl would attract help from others.These brain differences also explain the fact that more men take up jobs that require good spatial skills, while more women speech skills.It may all go back to our ancestors, among whom women needed speech skills to take care of their babies and men needed spatial skills to hunt, according to one research.
If all this disappoints you, it shouldn’t.“The brain changes throughout our lives according to what we do with it.”says a biologist.
1.Which of the following is true according to the first paragraph? ________.
A.Women’s brain is 10% less than men’s
B.Grey matter controls thinking in the brain.
C.Grey matter plays the same role as white matter.
D.Both sexes have the same amount of white matter.
2.What can we infer from the second and third paragraphs? ________.
A.Men do better dealing with one job at a time.
B.Women prefer doing many things at a time.
C.Women do not need to tell directions.
D.Men have weaker spatial abilities.
3.Which of the following do you agree with according to the fourth paragraph? _ A.More women take up jobs requiring speech skills
B.Young boys may be stronger than young girls.
C.Women may have stronger feelings than men.
D.Our ancestors needed more spatial skills.
4.What is the writer’s attitude in writing this passage? ________.
A.Defensive. B.Objective. C.Persuasive. D.Supportive.
高二英语阅读理解中等难度题查看答案及解析
Some birds are masters of crime. That means these species steal food from other birds and get away with it. Scientists have long wondered what these birds have in common. A new study suggests that big body size does not predict bad behavior. Instead, it is the size of the birds' brains that matters most.
To learn more about what makes some birds tend towards a life of crime and how they steal food from other birds, scientists analyzed 856 published reports of thieves. Researcher Julie says she started the project after watching birds steal dry dog food out of unattended bowls. She read about some dramatic examples of thieves, including birds that steal food from others flying in midair or bending through the sky. She learned that members of some species disturb other birds until they spit up food in their mouth.
Families that steal also tend to eat fish, mice, and other vertebrates (脊椎动物) instead of just insects. These meatier (多肉的)meals are hard to catch, and they deliver lots of valuable calories, so they are attempting to steal.
Finally, birds that steal tend to have big brains in relation to their bodies. That may seem surprising, since human bullies (欺凌弱小者)are often thought to be stronger in size. But for birds, stealing isn't about strength. It takes a clever brain to get food out of another hungry bird's claws, especially if that bird is bigger than you are.
1.What is the key factor of the birds' stealing food?
A.Body size. B.Living environment.
C.Brain size. D.Strength.
2.What can we learn from the last paragraph?
A.Stealing birds are often stronger.
B.For birds, stealing is about cleverness and tricks.
C.Birds steal food only from those that are smaller in size.
D.Birds that steal have small brains for their bodies.
3.The best title for the passage can be .
A.Diet Habits of a Feather
B.Hunting Skills of a Feather
C.Brains of a Feather
D.Thieves of a Feather
高二英语阅读理解中等难度题查看答案及解析
Hummingbirds (蜂鸟) are one of nature’s most energetic fliers and the only birds to hover in the air by relying on their strength alone.
Now scientists have found that it is the ratio (比值) of the bird’s wing length to its width that makes them so efficient. The discovery is helping experts compete with 42 million years of natural selection to build helicopters that are increasingly efficient.
David Lentink, an assistant professor at Stanford University in California, tested wings from 12 different species of hummingbirds, which he sourced from museums. He placed them on a machine used to test the aerodynamics (气力学) of the helicopter blades (桨叶). Professor Lentink’s team used the same machine to test the blades from an advanced micro-helicopter used by the UK’s army. They found that the micro-helicopter’s blades are as efficient at hovering as the average hummingbirds.
But while the micro-helicopter’s blades kept pace with the average hummingbird wings, they could not keep up with the most efficient hummingbird’s wing. The wings of Anna’s hummingbird were found to be about 27 percent more efficient than the man-made micro- helicopter’s blades.
While Professor Lentink wasn’t surprised at nature’s superiority, he said that helicopter blades have come a long way. “The technology is at the level of an average hummingbird,” he said. “A helicopter is really the most efficient hovering device that we can build. The best hummingbirds are still better, but I think it’s amazing that we’re getting closer. It’s not easy to match their performance, but if we build better wings with better shapes, we might match hummingbirds.”
Professor Lentink said that we don’t know how hummingbirds maintain their flight in a strong wind, how they navigate (确定方向) through branches, or how they change direction so quickly. He thinks that great steps could be made by studying wing aspect ratios—the ratio of wing length to wing width. Understanding these abilities and characteristics could be a benefit for robotics and will be the focus of future experiments.
1.What did the scientists find about hummingbirds?
A. Their wings are long and wide.
B. They can hover in the air for a long time.
C. The ratio of their wing length to wing width is very important.
D. They are the most energetic flier in nature.
2.Which is the right order of Professor Lentink’s research?
① Tested wings from different species of hummingbirds.
② Got resources from museums.
③ Analyzed the results and drew a conclusion.
④ Tested the blades from a micro-helicopter.
A. ①②③④ B. ②①③④ C. ②④①③ D. ②①④③
3.According to Professor Lentink, what will be the focus of future experiments?
A. To know how hummingbirds can fly in a strong wind.
B. To know how hummingbirds change direction so quickly.
C. To develop a new kind of helicopter.
D. To study the secrets of hummingbirds.
高二英语阅读理解困难题查看答案及解析