“Super-agers” have long puzzled scientists, b...

“Super-agers” have long puzzled scientists, but now researchers say they are unpicking why some people live beyond 80 and still appear to be well.

Researchers say studies show that super-agers appear to adapt more easily to the slings and arrows of life, and are more open-minded and less sensitive. But they have also made another discovery. Looking at the brains of 10 super-agers after they died, Prof Emily Rogalski, from Northwestern University said they discovered these individuals have more of a certain type of brain cell known as Von Economo neurons ( 神经) than average elderly individuals. “We can’t explain how they ended up with more Von Economo neurons or why that is important. But these are a special type of neurons that have only been found in a couple of regions of the brain.”

Studies have shown there are other differences as well. “When we look at the rate of cognitive ( 认知的) thinning in the cognitively average 80-year-olds, their brains are thinning at nearly two and a half times that of the super-agers,” said Rogalski.

Being underweight also seemed to matter, with those who had a very low body mass index after the age of 80 more likely to die. It’s not bad to be skinny when you’re young but it is when you’re old.

The researchers say they have also found that the common bad habits do not necessarily lead to an early grave, with many super-agers saying they smoked and enjoyed a drink. “We ask them why is it that you think you are a super-ager, how did you get here, and there are a couple of funny ladies and they will say, well it’s　 because I have some alcohol with my friends every day at 5 o’clock. Others have never had a drink,” said Rogalski.

However, Rogalski added, that did not mean that people should take up bad　 habits to live longer, noting that some people might have a genetic makeup that allowed them to tolerate smoking and drinking. Nonetheless, Rogalski thinks we can learn from super-agers. “We are getting quite good at extending our lifespan but our health span isn’t keeping up and what the super-agers have is more of a balance between those two, they are living long and living well,” she said.

1.What can we learn about Von Economo neurons?

A.They can be found all over the super-agers’ brains.

B.They lead to super-agers’ easier adaptation to hardships.

C.Super-agers are found to have more of them in their brains.

D.Scientists have discovered how they are produced in brains.

2.Compared to the average elderly, super-agers　 .

A.have better life habits

B.tend to drink more alcohol

C.are usually much slimmer

D.are slower in brain thinning

3.What does Rogalski intend to tell us by the underlined sentence?

A.We should develop good habits to live longer.

B.We should seek to live well while living long.

C.Super-agers should help us extend our health span.

D.Extending lifespan is harder than keeping health span.

4.What is the writer’s purpose in writing the passage?

A.To reveal some secrets of super-agers.

B.To introduce the ways of staying young.

C.To explain the advantages of living long.

D.To describe various habits of super-agers.

高二英语阅读选择中等难度题查看答案及解析

Most of the time, the ground feels solid beneath our feet. That's comforting. But it's also misleading because there's actually a lot going on underground. Masses of land (called plates) slip, slide, and bump against each other, slowly changing the shape of continents and oceans over millions and billions of years.

Scientists know that Earth formed about 4. 5 billion years ago. They also know that our planet was hot at first. As it cooled, its outermost layer, called the crust (地壳), eventually formed moving plates. Exactly when this shift happened, however, is an open question.

Now, an international group of researchers has an answer. They've found new evidence suggesting that Earth's crust started shifting at least 3. 8 billion years ago. The new estimate is 1. 3 billion years earlier than previous ones.

Not long before 3. 8 billion years ago, lots of small planets were hitting Earth, keeping its crust in a hot, melting state. After the hard crust formed, much of it sank at various times into the planet's hot insides. There, it melted before returning to the surface.

In some places, however, the crust never sank. One of the oldest such places is in Greenland, in an area called the Isua supracrustal (上地壳) belt. The rocky crust there is between 3. 7 and 3. 8 billion years old. The belt was once part of the seafloor, but now it is exposed to air.

The researchers recently took a close look at the Isua supracrustal belt. They noticed long, parallel cracks (裂缝) in the rock that have been filled in with a type of volcanic rock.

To explain this structure, the scientists propose that tension in the crust caused the seafloor to crack open long ago. Hot, liquid rock oozed from deep inside Earth to fill the cracks. Finally, the whole area cooled, forming what we see today.

That explanation, plus chemical clues inside the rock, suggests that the Isua supracrustal belt was once part of a plate under the ocean, beginning around 3. 8 billion years ago.

“It's a fantastic case of solving a jigsaw puzzle (拼图),” says one of the researchers. He notes that the puzzle was “ a very difficult one because these rocks are all very old and have been badly ruined".

1.What can we infer from the text?

A.The shapes of continents and oceans changed slowly.

B.The Earth's crust started shifting 1. 3 billion years ago.

C.The crust began to shift when the Earth was hot.

D.The hit from small planets made the Earth cool.

2.What do scientists know about the past of the Isua supracrustal belt?

A.It was once covered by the hot, liquid rock.

B.It remained under the deep sea.

C.It stayed hot and sinking.

D.It kept moving slowly.

3.The underlined phrase “oozed from” in Paragraph 7 is closest in meaning to

A.filled up gradually B.washed away quickly

C.flew out of slowly D.broke through suddenly

4.The text is mainly about 　　　　　　　 .

A.why the Earth cooled

B.how the Isua supracrustal belt formed

C.whether the ground beneath our feet is still

D.when Earth's crust began shifting

高二英语阅读选择中等难度题查看答案及解析

Why don’t birds get lost on their long migratory (迁居的) flights? Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks.

Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly mainly by night? Tests with artificial stars have proved conclusively that certain night-flying birds are able to follow the stars in their long-distance flights.

One such bird, a warbler(鸣禽) , had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky at migration time. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the direction of the make-be-live stars caused a change in the direction of his flight. Scientists think that warblers, when flying in daylight, use the sun for guidance. But the stars are apparently their main means of navigation (导航). What do they do when the stars are hidden by clouds? Apparently, they find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the warblers circle helplessly, unable to get their direction.

1.The reasons why birds don’t get lost on migratory flights__________.

2.Warblers migrate__________.

3.When the stars are hidden by clouds, warblers find their way by__________ .

4.This article is a good example of the way scientists__________ .

高二英语阅读理解困难题查看答案及解析

IT'S a mystery that has puzzled scientists. Five years ago, researchers found an area in the Atlantic Ocean seabed, where a part of the Earth's outer layer, or crust（地壳）, is　 missing. A thick layer of dark green rock, which is usually found deep inside the planet, lies exposed.

The crust, mantle(地幔) and core（地核） are the main layers that make up the planet. The mantle rests between the crust and the core.

Last month, a team of 12 British scientists set off on a six-week trip to study the hole in the crust.

The hole is about 4,800 meters below sea level and is believed to be more than 48,000 meters long and more than 48,000 meters wide. Scientists think that there are other nearby gaps. "It is like a window into the interior (内部) of the Earth," says scientist　　 Bramley Murton, who is part of the research team.

The site where the hole is located is part of a ridge (山脉) of undersea volcanoes.　 There, two of the plates that make up the Earth's surface meet. The plates are always　　 moving. When the plates move away from each other, lava rushes up from the mantle to　　 fill the gap and form a new crust. But this did not happen in the area where the hole is located.

The hole is giving researchers a good opportunity to study what's below the Earth's　　 surface. The team will use a special robotic tool to film the area and get samples of the exposed mantle. They hope to study everything from the chemistry of the oceans to how the Earth's surface behaves under the sea.

1. What's the title for the passage?

A. How to study the earth.

B. The formation of the earth.

C. A hole in the earth.

D. Studying the inside of the earth.

2.For the main layers of the earth, which one is right?

A. crust, mantle, core　　　　 B. seabed, crust, mantle

C. seabed, mantle, core　　　 D. crust, seabed, core

3.How does the hole come into being?

A. It's because of a volcano eruption.

B. It's because of the plates movements

C. It's because lava rushes up from the mantle

D. It's not clear from the passage.

4.By studying the hole, the scientists want to do the following except____.

A. knowing what's below the Earth's surface

B. getting samples of the exposed mantle

C. getting the film of the hole

D. studying the chemistry of the oceans

高二英语阅读理解中等难度题查看答案及解析

Scientists have been studying how people use money for long. Now they’re finding some theories may apply to one group of monkeys.

Researchers recently taught six monkeys hos to use money. They gave the monkeys small metal disks (圆片) that could be used like cash and showed them some yummy apple pieces. The monkeys soon figured out that if tyey gave one of the disks to a scientist, they’d receive a piece of apple in return.

If you think that is all the monkeys can figure out, you are wrong. Two researchers, Jake and Allison, acted as apple sellers in the experiments. The monkeys were tested one at a time and had 12 disks to spend in each experiment. Jake always showed the monkeys on apple piece, while Allison always showed two pieces. But that’s not necessarily what they gave the monkeys. The number of apple pieces given for a disk was determined at random.

Experiment One: Allison showed two pieces of apples but gave both piece only half the time. The other half, she took one piece away and gave the monkey just the remaining piece. Jake, on the other hand, always gave exactly what he showed: one piece for each disk. The monkeys chose to trade more with Allison.

Experiment Two: Allison continued to sometimes gave two pieces and sometimes one piece. But now, half the time, Jake gave the one apple piece he was showing, and half the time he added a bonus. Guess what? The monkeys chose to trade more with Jake.

In the first experiment, the monkeys correctly figured out that if they traded with Allison, they’d end up with more treats. In the second one, when a monkey received two pieces from Jake, it seemed like a gain. When Allison gave the monkey only one piece instead of the two she showed, it seemed like a loss. The monkeys preferred trading with Jake because they’d rather take a chance of seeming to win than seeming to lose.

We also sometimes make silly business decisions just to avoid the feeling that we’re getting less, even when we’re not. Would you have made the same choices?

1.What conclusion might experts draw from the first experiment?

A. People are smarter in terms of finance.

B. It’s easy to teach monkeys how to trade.

C. Business theories can apply to all monkeys.

D. The monkeys show certain business sense.

2.What does “a bonus” in paragraph 5 refer to?

A. A coin.　　 B. A chance.

C. A metal disk.　　 D. An apple piece.

3.Why did the monkeys choose to trade more with Jake in the second experiment?

A. Because they didn’t like the feeling of losing.

B. Because they get more apple pieces from Jake.

C. Because Jake always gave them two apple pieces.

D. Because the apple pieces from Jake were yummy.

4.What could be the best title for the passage?

A. Disk for Apple: Who to Trade with?

B. Shopping for Bargain: Same of different?

C. Moneky’s Business Sense: Smart or Silly?

D. People’s Business Decision: Lose or Gain?

高二英语阅读理解简单题查看答案及解析

For as long as they can remember, Jynne Martin and April Surgent had both dreamed of going to Antarctica. This winter, they each made it to the icy continent as guests of the National Science Foundation (NSF). But they didn't, as scientists. Martin is a poet and Surgent is an artist. They went to Antarctica as participants in the NSF's Artists and Writers Program, which makes it possible for artists, including filmmakers and musicians, to experience Antarctica and contribute their own points of view to our understanding of the continent.

“It's important for scientists and artists to work together,” says Surgent, who spent six weeks at Palmer Station, the smallest of the U.S. research bases. “You need a lot of different ways and points of view to explain the world.”

Martin followed four scientific teams on the ice and wrote articles and poems inspired by her experience. “Each day was the new ‘best day of my life’.” said Martin, who said she also loved spending time in the library at the McMurdo Station reading the journals of early explorers.

Today's scientists write articles for scientific journals. Unlike the early explorer's journals, scientific papers can now be very difficult for non-scientists to understand. Writers in Antarctica work to explain the research to the public. Peter Rejcek is editor, writer, and photographer for the Antarctic Sun, an online magazine devoted to news about the U.S. Antarctic Program. He goes to the South Pole every year, interviewing the scientists about their research.

Antarctica is full of stories and wonders that are scientific, historical, and personal. People such as Martin, Surgent, and Rejcek are making an effort to bring those stories to as many people as they can.

“Some people are going to be scientists, some people are going to be artists, some people are going to be journalists, but we can all work together,” says Surgent, "to celebrate this extraordinary place.”

1.What is the main purpose of the NSF's Artists and Writers Program?

A.To increase people's understanding of Antarctica.

B.To develop a relationship between scientists and artists.

C.To encourage artists and writers to learn science.

D.To make the scientists in Antarctica known to the public.

2.Which of the following best explains why scientists and artists work together?

A.The world is full of different people. B.The world should move in harmony.

C.The world is full of different opinions. D.The world should be seen in different ways.

3.Where is the library in which Martin spent time reading?

A.At the Antarctic Sun. B.At a research base in the USA.

C.At a research base in Antarctica. D.At the National Science Foundation.

4.It can be inferred from the text that articles by writers about Antarctica　　　　　 .

A.are hard for people to understand B.are easy for people to understand

C.have nothing to do with the research D.are mainly about early explorers

高二英语阅读选择中等难度题查看答案及解析

The predictability of our death rates is something that has long puzzled social scientists. After all, there is no natural reason why 2,500 people should accidentally shoot themselves each year or why 7,000 should drown or 55,000 die in their cars. No one establishes a quota (定额) for each type of death. It just happens that they follow a consistent pattern year after year.

A few years ago a Canadian psychologist named Gerald Wilde became interested in this phenomenon. He noticed that mortality rates for violent and accidental deaths throughout the Western world have remained strangely static throughout the whole of the century, despite all the technological advances and increases in safety standards that have happened in that time. Wilde developed an interesting theory called “risk homeostasis”. According to this theory, people naturally live with a certain level of risk. When something is made safer, people will get around the measure in some way to get back to the original level of danger. If, for instance, they are required to wear seat belts, they will feel safer and thus will drive a little faster and a little more recklessly, thereby statistically canceling out the benefits that the seat belt offers. Other studies have shown that where a crossing is made safer, the accident rate invariably falls there but rises elsewhere along the same stretch of road as if making up for the drop. It appears, then, that we have an inborn need for danger. In all events, it is becoming clearer and clearer to scientists that the factors influencing our lifespan are far more subtle and complex than had been previously thought. It now appears that if you wish to live a long life, it isn’t simply a matter of paying attention to certain precautions such as eating the right foods, not smoking, and driving with care. You must also have the right attitude. Scientists at the Duke University Medical Center made a 15-year study of 500 persons personalities and found, somewhat to their surprise, that people with a suspicious or mistrustful nature die prematurely far more often than people with a sunny disposition. Looking on the bright side, it seems, can add years to your life span.

1.What social scientists have long felt puzzled about is why __________.

A. the death rate can not be predicted

B.the death toll remained stable year after year

C.a quota for each type of death has not come into being

D.people lost their lives every year for this or that reason

2.In his research, Gerald Wilde finds that technological advances and increases in safety standards __________.

A.have helped solve the problem of so high death rate

B.have oddly accounted for death rates in the past century

C. have reduced death rates for violent and accidental deaths

D. have achieved no effect in bringing down the number of deaths

3.According to the theory of “risk homeostasis”, some traffic accidents result from ___________.

A. our inborn desire for risk

B. our fast and reckless driving

C. our ignorance of seat belt benefits

D. our instinctive interest in speeding

4.By saying “statistically canceling out the benefits that the seat belt offers” (Para. 2), the author means __________.

A. wearing seat belts does not have any benefits from the statistic point of view

B. deaths from wearing seat belts are the same as those from not wearing them

C. deaths from other reasons counterbalance the benefits of wearing seat belts

D. wearing seat belts does not necessarily reduce deaths from traffic accidents

5.Which of the following may contribute to a longer life span?

A. Showing adequate trust instead of suspicion of others

B. Eating the food low in fat and driving with great care

C. Cultivating an optimistic personality and never losing heart

D. Looking on the bright side and developing a balanced level of risk

高二英语阅读理解中等难度题查看答案及解析

It is a question that has long puzzled scientists—exactly why are tigers orange? One might think it makes them more obvious-particularly against a leafy green forest background. William Blake summed it up in his famous poem known by generations of schoolchildren: “Tyger, tyger, burning bright / In the forest of the night.” But now the answer is at hand.

While obvious to us, computer simulations (模拟) of what the big cats look to the main animals they hunt for, deer, show a different picture. Humans with normal colour vision, can see red, blue and green colours. But deer can only pick up blue and green light, they are effectively colourblind to the colour red, like some humans. It means the tigers’ orange colouration looks green to them, allowing them to mix perfectly into the background, new research claims.

Dr John Fennell at the University of Bristol and colleagues said that they used computers to estimate how noticeable a given animal was. They did this by using images of the environment in which the animal lives, and then creating images to see whether the camouflage helps the animal to mix in.

Dr Fennell writes that by simulating what the world looks like to animals who are “two-colour vision”—someone who cannot discover the difference between red and green—“we also identify the most suitable colours for hiding and visibility”.

Dr Fennell writes in the Royal Society Journal Inter face: “Considering the coat of a tiger, it has fur that appears orange to a three-colour vision observer rather than some shade of green, though the latter should be more appropriate color for an attack hunter in forests. However, when viewed as a two-colour vision observer, the tiger’s colour is very effective.”

The question then arises as to why tigers don’t grow green coats. Dr Fennell and colleagues write that mammals (哺乳动物) are not able to produce green fur. To do so would “require a significant change to mammalian biochemistry”. There is only one mammal known to have green fur but this is achieved through what might be considered as, well, cheating, not exactly real.

1.Why does the author mention the poem in paragraph 1?

A.To arouse reader s interest in poems.

B.To show the authors respect to the poet.

C.To answer the question of the color of the tiger

D.To stress the noticeable color of the tiger to us.

2.What color is inexistent in the eyes of deer?

A.Black. B.Red.

C.Blue. D.Green.

3.What does the underlined word “camouflage” mean in paragraph 3?

A.The cover of something.

B.The images of something.

C.The way of hiding something.

D.The way of hunting for something.

4.What can be inferred from the last paragraph?

A.The colour of tigers sometimes cheats people.

B.Getting green may prevent tigers from being extinct.

C.There are no mammals with real green fur in the world.

D.The tigers’ fur will probably evolve into green in the future.

高二英语阅读理解中等难度题查看答案及解析

Scientists believe they could bring the likes of dodos(渡渡鸟)back from the dead through cloning experiments in the near future which could see the flightless birds revived from their extinction.

The big bird, which was about a metre tall and weighed up to 18 kilograms, was native to Mauritius but became extinct in the 1600s, shortly after humans discovered the island. However, 400 years later, scientists now believe that they could bring the dodo back to life through cloning of some of its closest living relatives.

Scientists recently published a paper which identified the overall genomic structure of dinosaurs. The team achieved this by tracing the ancestors (祖先)of birds — the dinosaurs closest living relatives — to create the genomic structure. Researchers involved in the study say it is an emphatic ‘no’ when it comes to the possibility of ever being able to clone dinosaurs, but they do say that more recently extinct birds like the carrier pigeon and the dodo could be brought back due to the fact that they have such close living relatives.

University of Kent scientists Darren Griffin and Rebecca O’Connor wrote in an article for The Conversation: “We discovered that birds and most flightless dinosaurs had a lot of chromosomes (packages of DNA). Having so many allows animals to generate variation, the driver of natural selection.”

“However, though it is a long shot, it may be possible in future to use Jurassic Park technology to help avoid some of the harm that humans have caused. Mankind has seen the extinction of well-known avian dinosaurs such as the dodo and the passenger pigeon.”

“Recovery(恢复)of DNA that is a only few hundred years old from these birds is a far more realistic way. It may also be that eggs from closely related living species might just be good enough. In the right conditions we may be able to use them to resurrect some of these species from extinction.”

1.What can we learn about dodos?

A.They flew to Mauritius in the 1600s. B.They could be used to clone pigeons.

C.They would die out in the near future. D.They might be brought back to life soon.

2.How do scientists revive dodos?

A.They clone dodos’ closest living relatives. B.They trace those endangered birds closely.

C.They look for dinosaurs’ living conditions. D.They identify genomic structure of pigeons.

3.What does the underlined word “resurrect” in the last paragraph mean?

A.Learn. B.Protect.

C.Revive. D.Prevent.

4.What is the best title for the text?

A.Scientists Expect to Clone the Dodos. B.Scientists Find Close Living Relatives.

C.Dinosaurs Have Already Been Extinct. D.Some Species Have Been Discovered.

高二英语阅读选择中等难度题查看答案及解析

Recent research findings have ________ the origin of our universe, which has puzzled the scientific world.

A. cast light on　　 B. given rise to

C. seized control of　　 D. kept company with

高二英语单项填空中等难度题查看答案及解析