Research suggests that a newly-identified gene known as insomniacs(失眠症患者) may play a role in keeping us asleep. By cloning and testing this gene in about 21,000 fruit flies, Rockefeller University researchers say they have discovered an entirely new mechanism (机制) by which sleep is controlled.
By studying these flies, the researchers discovered that mutations(变异) in the insomniac gene were associated with a great reduction in sleep. While a typical fruit fly slept for an average of 927 minutes a day, the mutant flies slept for just 317. They also slept for shorter periods of time, and slept and woke more frequently.
“The results showed a great loss of both the time that the flies’ sleep lasted and their ability to remain asleep after they slept,” says researcher Nicholas Stavropoulos.
The researchers also examined the link between sleep and lifespan, finding that flies with mutations to the insomniac gene lived only about two-thirds as long as unchanged flies. But when the scientists removed insomniac only in neurons（神经细胞）---allowing it to remain in the rest of the flies’ bodies---this difference disappeared; the resulting animals slept poorly but lived just as long.
“This suggests that reduced sleep can be ‘uncoupled’(分开) from reduced lifespan, supporting the idea that some interruptions of sleep do not affect overall health, at least as far as lifespan is concerned,” Stavropoulos says.
Although flies and humans would appear to have little in common when it comes to lifestyle, scientists say that the mechanisms of sleep and wakefulness are likely to be quite similar.
“Sleep is a fundamental behavior in all animals, and it is poorly understood from a scientific standpoint, says Stavropoulos. This work could prove useful in understanding and treating sleep disorders”The text is mainly about____.
| A．the progress in cloning fruit flies |
| B．the methods of cloning fruit flies |
| C．the link between gene and lifespan |
| D．the influence of a gene on the ability to sleep |
According to paragraph2, the mutant flies________.
| A．slept about 5 hours a day |
| B．had problems waking up |
| C．didn’t seem sleepy at all |
| D．could not fall asleep |
We can conclude from the text that________.
| A．sleep and health go hand in hand |
| B．sleep can be controlled by humans |
| C．research into sleep is very fruitful |
| D．the findings are useful in medical treatment |
Many scientists are now exploring the idea of going to live on Mars. Some other scientists from the MASA AMES Center(美国宇航局) have already started the creation of a “Mars town” and many others are in fact already experimenting with it. Of course, these experiments are done on Earth itself but this “Mars town” has an environment practically like that of Mars.
The astronauts working in these towns wear their space suit and also do everything they would really have to carry out if they ever go to Mars in the future.
But Mars would be like Earth, a temporary（临时的） place for humans. When the Sun starts swallowing up(吞掉) the planets, Mars will disappear only hours after Earth. So Mars only seems to be the ideal place to spread the human beings. It is also a good location to send humans if ever there is a disaster on Earth. By saying disaster, I mean asteroids(小行星) hitting and things like that.
If we humans do not want to disappear when Earth or Mars gets swallowed up, we will have to go and live beyond the solar system. But are there any planets outside our solar system prepared to support life? Astronomers’ answer is:
“If Earth can support life, why can’t other planets do the same too? Astronomers have already discovered a Jupiter(木星)- like planet orbiting a Sun-like star, so why not an Earth-like planet orbiting a Sun-like star?
To achieve this goal though, many other problems have to be taken into consideration. How do we transform(改造) a dusty planet like Mars into one more or less like our Earth? How should we go on? There is still a long way to go. The “Mars town” mentioned in the passage is ___________
| A．a research base on Mars. |
| B．an experimental lab built on Earth. |
| C．a strange place on Mars . |
| D．a town existing in scientists’ imagination |
We can know from the passage that astronomers probably think ____________
| A．it is impossible to transport humans to other planets. |
| B．there may be an Earth-like planet outside the solar system |
| C．humans will move to the new-found Jupiter-like planet |
| D．there’s no need for humans to move beyond the solar system. |
Why would Mars only be a temporary(临时) place for humans?
| A．The conditions there would be too hard for the human beings |
| B．There would be more disasters like asteroids hitting. |
| C．It would disappear when Earth disappeared. |
| D．It would be too hot to live on. |
The underlined word “orbiting” in the fifth paragraph is closest in meaning to “________”
| A．moving around | B．getting close to |
| C．passing by quickly | D．going through |
Which of the following would be the best title for this passage?
| A．Mars Town | B．Living on Mars |
| C．The Future of Earth | D．Where to live in the Future |
If there is one thing I am sure about, it is that in a hundred years from now we will still be reading newspapers. It is not that newspapers are a necessity. Even now some people get most of their news from television or radio. Many buy a paper only on Saturday or Sunday. But for most people reading a newspaper has become a habit passed down from generation to generation.
The nature of what is news may change. What basically makes news is what affects our lives- the big political stories, the coverage of the wars, earthquakes and other disasters, will continue much the same. I think there will be more coverage of scientific research, though. It’s already happening in areas that may directly affect our lives, like genetic(基因) engineering. In the future, I think there will be more coverage of scientific explanations of why we feel as we do --- as we develop a better understanding of how the brain operates and what our feelings really are.
It’s quite possible that in the next century newspapers will be transmitted(传送) electronically from Fleet Street and printed out in our own home. In fact, I am pretty sure that it will happen in the future. You will probably be able to choose from a menu, making up your own newspaper by picking out the things you want to read- sports and international news, etc.
I think people have got it wrong when they talk about competition between the different media(煤体). They actually feed off each other. Some people once foresaw that television would kill off newspapers, but that hasn’t happened. What is read on the printed page lasts longer than pictures on a screen or sound lost in the air. And as for the Internet, it is never really pleasant to read something just on a screen. What is the best title for the text?
| A．The Best Way to Get News | B．The Changes of Media |
| C．Make Your Own Newspaper | D．The Future of Newspapers |
In the writer’s opinion, in the future, ___________.
| A．more big political affairs, wars and disasters will make news |
| B．newspapers will not be printed in publishing houses any longer. |
| C．newspapers will cover more scientific research |
| D．more and more people will watch TV. |
What will probably be on in the newspaper made by yourself?
| A．Sports and international news. | B．A menu of important news |
| C．The most important news. | D．What you are interested in |
From the text, we can infer that _____________.
| A．newspapers will win the competition among the different media |
| B．newspapers will stay with us together with other media |
| C．television will take the place of newspapers. |
| D．some media will die out |
The underlined phrase “feed off” in the last paragraph means ___________.
| A．depend on | B．compete with | C．fight with | D．kill of |
Inventor, physicist, surveyor, astronomer, biologist, artist… Robert Hooke was all there and more. Some say he was the greatest experimental scientist of the 17th century. In the course of his work, he cooperated with famous men of science like Isaac Newton, and the great architect, Christopher Wren.
Hooke’s early education began at home, under the guidance of his father. He entered Westminster School at the age of 13, and from there went to Oxford, where he came in contact with some of the best scientists in England. Hooke impressed them with his skills at designing experiments and inventing instruments. In 1662, at he age of 28, he was named Curator of Experiments at the newly formed Royal Society of London- meaning that he was responsible for demonstrating(展示) new experiments at the society’s weekly meeting. Hooke accepted the job, even though he knew that the society had no money to pay him!
Watching living things through a microscope was one of his favourite pastimes(消遣). He invented a compound microscope(显微镜) for this purpose. One day while observing a cork(软木塞) under a microscope, he saw honeycomb-like structures. There were cells –the smallest units of life. In fact, it was Hooke who invented the term “cell” as the boxlike cells of the cork reminded him of the cells of a monastery(修道院).
Another achievement of Hooke’s was his book Micrographia, which introduced the enormous potential(潜力) of the microscope. It contains fascinating drawings of the thing he saw under the microscope. The book also includes, among other things, ideas on gravity, light and combustion(燃烧) that may have helped scientists like Newton when they were developing their own theories on these phenomena(现象).
Hooke made valuable contributions to astronomy too. A crater(火山口) on the moon is named after him in honour of his services to this branch of science. We can infer from paragraph 2 that Hooke is ____________.
| A．friendly | B．sociable | C．creative | D．helpful |
Which is the possible reason why Hooke accepted the job as Curator of Experiments?
| A．He liked designing experiments. |
| B．His family needed his support. |
| C．He wanted to please the famous scientists in England. |
| D．His parents couldn’t afford his education. |
The cell got its name because of __________.
| A．its use | B．its shape | C．Hooke’s favourites | D．Hooke’s experiences |
Which of the following is true according to the text?
| A．Hooke went to Oxford in 1645. |
| B．Hooke was well paid in the Royal Society of London. |
| C．Hooke made a contribution to medicine. |
| D．Hooke’s book Micrographia may have helped Newton. |
The last paragraph is to prove that _____________.
| A．Hooke was the greatest experimental scientist of the 17th century |
| B．Hooke was good at making discoveries |
| C．Hooke’s contributions were not limited to one field |
| D．Hooke was one of the greatest astronomers |
London has more than nine million visitors every year. They come and visit some of the most famous places in England: Big Ben, the Tower of London and the River Thames.
You can see some of the most interesting places in London by getting on the tour buses. Or you can take a ride on the London Eye. This large wheel slowly takes you 135m above the River Thames.
The River Thames is London’s main waterway. It has shaped the capital’s landscape, history and geography. So one of the best ways of knowing more about the city is to take a trip along the river.
The clock tower of the Houses of Parliament, Big Ben, has become one of the main symbols of London. The sound of the bell, which you can hear at the beginning of many television and radio programmes, has become well-known throughout the nation.
No visit to London is complete without a look at the Tower of London, in the eastern part of the city. After Big Ben, the Tower may be London’s most visited tourist spot. Directly south is Tower Bridge, which is more than100 years old.
Along all the palaces in London, Buckingham Palace is the most famous. It has been the main London home of the royal family since Queen Victoria moved there in 1873. You can visit some of the rooms in August and September. And most mornings of the year you can watch the soldiers
outside changing the guard.
About one hour by train out of London is the Tower of Windsor. Here you can visit another of the Queen’s homes-Windsor Castle. There was a fire in 1992 and many of the rooms were badly burned. But now they are full of beautiful pictures, tables and chairs again.
Sightseeing in London is great, but it can get very tiring. So, the best way to start the day is to fill up with an English breakfast.
You can buy an English breakfast in nearly every hotel, and at many restaurants and cafes. An English pub is a good place to stop for lunch and a drink. You can get hot or cold food and try one of England’s many ales(浓啤酒). Fish and chips are also a traditional English meal. So look out for fish and chip shops in cities as well as by the sea.
Or you can sit outside one of the many roadside pubs and cafes in London, and simply watch the busy world go by.We can learn from the text that ____________.
| A．Windsor Castle has been rebuilt |
| B．the Big Ben can be heard everywhere in London |
| C．only some of the hotels in England serve breakfast. |
| D．the London Eye can carry you where you like to go |
Which place may be London’s most visited tourist spot?
| A．Buckingham Palace | B．The Tower of London |
| C．Big Ben | D．The River Thames |
If you go to London in December, you will not be able to ___________
| A．visit Windsor Castle |
| B．tour the Buckingham Palace |
| C．tour the city along the River Thames |
| D．watch the soldiers outside the Buckingham Palace changing guards. |
The underlined word “landscape” (paragraph 3) is closest in meaning to _________.
| A．sights | B．interests | C．characteristics | D．culture |
The whole passage mainly introduces the ________________.
A. tourism in London B. tourists in London
B. history in London D. sightseeing in London
Looking back on my childhood, I am convinced that naturalists are born and not made．Although we were all brought up in the same way, my brothers and sisters soon abandoned their pressed flowers and insects．Unlike them, I had no ear for music and languages．I was not an early reader and I could not do mental arithmetic．
Before World War I we spent our summe
r holidays in Hungary．I have only the dim memory of the house we lived in, of my room and my toys．Nor do I recall clearly the large family of grandparents, aunts, uncles and cousins who gathered next door．But I do have a clear memory of the dogs, the farm animals, the local birds, and above all, the insects．
I am a naturalist, not a scientist．I have a strong love of the natural world and my enthusiasm led me into varied investigations．I love discussing my favorite topics and enjoy burning the midnight oil while reading about other people’s observations and discoveries．Then something happens that brings these observations together in my conscious mind．
Suddenly you fancy you see the answer to the riddle, because it all seems to fit together．This has resulted in my publishing 300 papers and books, which some might honor with the title of scientific research．
But curiosity, a keen eye, a good memory and enjoyment of the animal and plant world do not make a scientist: one of the outstanding and essential qualities required is self-discipline, a quality I lack．A scientist requires not only self-discipline, but hard training, determination and a goal．A scientist, up to a certain point, can be made．A naturalist is born．If you can combine the two, you get the best of both worlds．The first paragraph tells us the author _____．
| A．was interested in flowers and insects in his childhood |
| B．lost his hearing when he was a child |
| C．didn’t like his brothers and sisters |
| D．was born to a naturalist’s family |
The author can’t remember his relatives clearly because _____．
| A．he didn’t live very long with them |
| B．the family was extremely large |
| C．he was too young when he lived with them |
| D．he was fully occupied with observing nature |
The author says that he is a naturalist rather than a scientist probably because he thinks he _____．
| A．has a great deal of trouble doing mental arithmetic |
| B．lacks some of the qualities required of a scientist |
| C．just reads about other people’s observations and discoveries |
| D．comes up with solutions in a most natural way |
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