In order to protect valuable energy, snails(蜗牛) basically play a game of follow-the-leader, a new study finds. Snails create trails of mucus(黏液) to help them move smoothly across the ground, mainly in search of food or a partner, but making all that mucus uses up a lot of energy.
“Snails use a lot of energy, probably a third, creating mucus,” said Mark Davies of the University of Sunderland, lead author of the study published in the journal Proceedings of the Royal Society. “This process is very tiring indeed— much more so than walking, swimming or flying.”
Davies and his workmates studied marine snails off the coast of Britain and discovered that to save some of this important energy, the snails sometimes follow the existing mucus trails laid down by other snails to get around and so only have to create a small part of the mucus needed to make a new trail.
“The fact that they can make savings has an effect on as much as they have to save more energy to do other things like reproducing,” Davies said.
The energy saving may also help snails which live in environments where food is not enough, making the energy harder to replace.
Biologists had long guessed that snails behaved this way, but this is the first study to directly observe it. Davies said that it is likely that all snails use this means of cutting energy as they work hard through life.
45. What’s the function of mucus that snails create?
A. To find their food B. To find their way back
C. To save their energy D. To help them move smoothly
46. According to the passage, which of the following statements is TRUE?
A. The snail’s life is very hard.
B. The snails don’t need much to reproduce.
C. This is the first time to do the guess.
D. The snails will replace more energy in places lacking food.
47. From the passage we know that ______.
A. snails’ trails are sometimes reused
B. snails’ food is difficult to find
C. snails can live a long life
D. only marine snails have the ability
48. What does the passage mainly talk about?
A. How snails move and work.
B. Snails save energy by reusing mucus trails.
C. A new study finds the mysteries of snails.
D. Snails make full use of their energy.
Stephen William Hawking was born on 8 January, 1942 (300 years after the death of Galileo) in Oxford, England. His parents’ house was in north London, but during the Second World War Oxford was considered a safer place to have babies. When he was eight, his family moved to St Albans, a town about 20 miles north of London. At eleven Stephen went to St Albans School, and then on to University College, Oxford, his father’s old college. Stephen wanted to do Mathematics, although his father would have preferred Medicine. Mathematics was not available at University College, so he did Physics instead. After three years and not very much work he was awarded a First Class Honours degree in Natural Science.
Stephen then went on to Cambridge to do research in Cosmology, there being no one working in that area in Oxford at that time. His supervisor was Denis Sciama, although he had hoped to get Fred Hoyle who was working in Cambridge. After gaining his Ph. D. he first became a Research Fellow, and later on a Professorial Fellow at Gonville and Caius College. After leaving the Institute of Astronomy in 1973 Stephen came to the Department of Applied Mathematics and Theoretical Physics, and since 1979 has held the post of Lucasian Professor of Mathematics. The chair was founded in 1663 with money left in the will of the Reverend Henry Lucas, who had been the Member of Parliament for the University. It was first held by Isaac Barrow, and then in 1663 by Isaac Newton.
Professor Hawking has twelve honorary degrees, was awarded the CBE in 1982, and was made a Companion of Honour in 1989. He is the recipient of many awards, medals and prizes and is a Fellow of The Royal Society and a Member of the US National Academy of Sciences. Stephen W. Hawking went to the same college as ______ at his teenage.
| A．Galileo |
| B．his father |
| C．Isaac Barrow |
| D．Isaac Newton |
Which of the following shows the right order of what happened to Hawking?
a. He gained his Ph. D.
b. He went to Cambridge.
c. He was given a First Class Honours degree.
d. He began to hold the post of Lucasian Professor of Mathematics.
e. He went to St Albans School.
A. e-c-b-a-d B. a-e-c-d-b
C. a-e-c-b-d D. c-b-d-e-a According to the passage, Stephen W. Hawking had never spent much time studying _____.
| A．Cosmology |
| B．Mathematics |
| C．Physics |
| D．Medicine |
Before Stephen W. Hawking went to Cambridge,_______ .
| A．there was no one studying Cosmology in England |
| B．there was no one studying Cosmology in Oxford |
| C．there were only a few scientists studying Cosmology in Oxford |
| D．Cosmology is widely studied in Britain |
Why play games? Because they are fun, and a 1ot more besides. Following the rules…planning your next move...acting as a team member…these are all “game” ideas that you will come across throughout your life.
Think about some off the games you played as a young child, such as rope-jumping and hide-and-seek. Such games are entertaining and fun. But perhaps more importantly, they translate life into exciting dramas that teach children some of the basic rules they will be expected to follow the rest of their lives, such as taking turns and cooperating (合作) .
Many children's games have a practical side Children around the world play games that prepare them for work they will do as grown-ups. For instance, some Saudi Arabian children play a game called bones. Which sharpens the hand-eye coordination（协调）needed in hunting.
Many sports encourage national or local pride. The most famous games of all, the Olympic Games, bring athletes from around the world together to take part in friendly competition. People who watch the event wave flags, knowing that a gold medal is a win for an entire country , not just the athlete who earned it. For countries experiencing natural disasters or war, an Olympic win can mean so much.
Sports are also an event that unites people. Soccer is the most popular sport in the world. People on all continents play it—some for fun and some for a living. Nicolette Iribarne, a Californian soccer player, has discovered a way to spread hope through soccer. He created a foundation to provide poor children with not only soccer balls but also a promising future.
Next time you play your favorite game or sport, think about why you enjoy it, what skills are needed, and whether these skills will help you in other aspects of your life.Through playing hide-and-seek, children are expected to learn to ________.
| A．be a team leader |
| B．obey the basic rules |
| C．act as a grown-up |
| D．predict possible danger |
The underlined part in Paragraph 2 most probably means that games can________
| A．describe life in an exciting way |
| B．turn real-life experiences into a play |
| C．make learning life skills more interesting |
| D．change people's views of sporting event s |
Iribarne's goal of forming the foundation is to _______.
| A．bring fun to poor kids |
| B．provide soccer balls for children |
| C．give poor kids a chance for a better life |
| D．appeal to soccer players to help poor kids |
What can be inferred from the passage?
| A．Ga med benefit people all their lives. |
| B．Sports can get all athletes together. |
| C．People are advised to play games for fun. |
| D．Sports increase a country's competitiveness. |
Every day we experience one of the wonders of the world around us without even realizing it. It is not the amazing complexity of television, nor the impressive technology of transport. The universal wonder we share and experience is our ability to make noise without mouths, and so transmit ideas and thoughts to each other's minds. This ability comes so naturally that we tend to forget what a miracle (奇迹) it is.
Obviously, the ability to talk is something that marks humans off from animal. Of course, some animals have powers just as amazing, Birds can fly thousands miles by \observing positions of the stars in the sky in relation to the time of day and year. In Nature's talent show, humans are a species of animal that have developed their own special act. If we reduce it to basic terms, it's an ability for communicating information to others, by varying sounds we make as we breathe out.
Not that we don't have other powers of communication. Our facial expressions convey our emotions, such as anger, or joy, or disappointment. The way we hold our heads can indicate to others whether we are happy or sad. This is so-called “body language”. Bristling (直立的) fur is an unmistakable warning of attack among many animals. Similarly, the bowed head or drooping tail shows a readiness to take second place in any animal gathering.
Such a means of communication is a basic mechanism that animals, including human beings, instinctively acquire and display. Is the ability to speak just another sort of instinct? If so, how did human beings acquire this amazing skills ? Biologist can readily indicate that particular area of our brain where speech mechanisms function, but this doesn't tell us how that part of our bodies originated in our biological history. According to the passage, the wonder we take for granted is .
| A．our ability to use language |
| B．the miracle of technology |
| C．the amazing power of nature |
| D．our ability to make noises with mouth |
What feature of “body language” mentioned in the passage is common to both human an animals?
| A．Lifting heads when sad. |
| B．Keeping long faces when angry. |
| C．Bristling hair when ready to attack. |
| D．Bowing heads when willing to obey. |
What can be inferred from Paragraph 3?
| A．Body language is unique to humans. |
| B．Animals express emotions just as humans do. |
| C．Humans have other powers of communication. |
| D．Humans are no different from animals to some degree. |
This passage is mainly about .
| A．the development of body language. |
| B．the special role humans play in nature |
| C．the power to convey information to others |
| D．the difference between humans and animals in language use |
How words came into being is unknown.All we assume is that some early men invented cortain sounds,in one way or another,to express thoughts and feelings,actions and things,so that they could talk with each other.Later they agreed upon certain signs,called letters,which could be put together to show those sounds,and which could be written down.Those sounds,whether spoken or written in letters,are called words.
The power of words,then,lies in their associations-the things they bring up to our minds.Words become filled with meaning for us by experience;and the longer we live,the more certain words bring back to us the happy and sad events of our past;and the more we read and learn,the more the number of words that mean something to us increases.
Great writers are those who not only have great thoughts but also express these thoughts in words which have powerful effects on our minds and feelings.This clever use of words is what we call literary style.Above all,the real poet is a master of words.He can express his meaning in words which sing like music,and which by their position and association can move men to tears.We should therefore learn to choose our words carefully and use then correctly,or they will make our speech silly and common.We learn from the text that language might have begun with________.
| A．expressions |
| B．actions |
| C．signs |
| D．sounds |
What is mainly discussed in Faragraph 2?
| A．The ……of new words |
| B．The importance of old words |
| C．The relation of human experience with words |
| D．The gradual change and development of words |
In the last paragraph,what does the anthor suggest that we should do?
| A．Use words skilfully |
| B．Make musical speeches |
| C．Learn poems by heart |
| D．Associate with listeners |
The 2012 London Olympics had enough problems to worry about. But one more has just been added - a communications blackout caused by solar storms.
After a period of calm within the Sun, scientists have detected the signs of a flesh cycle of sunspots that could peak in 2012, just in time for the arrival of the Olympic torch in London.
Now scientists believe that this peak could result in vast solar explosions that could throw billions of tons of charged matter towards the Earth, causing strong solar storms that could jam the telecommunications satellites and interact links sending five Olympic broadcast from London.
"The Sun's activity has a strong influence on the Earth. The Olympics could be in the middle of the next solar maximum which could affect the functions of communications satellites," said Professor Richard Harrison, head of space physics at the Rutherford Appleton Laboratory in Oxfordshire.
At the peak of the cycle, violent outbursts called coronal mass ejections (日冕物质抛射) occur in the Sun's atmosphere, throwing out great quantities of electrically-charged matter. " A coronal mass ejection can carry a billion tons of solar material into space at over a million kilometers per hour. Such events can expose astronauts to a deadly amount, can disable satellites, cause power failures on Earth and disturb communications," Professor Harrison added. The risk is greatest during a solar maximum when there is the greatest number of sunspots.
Next week in America, NASA is scheduled to launch a satellite for monitoring solar activity called the Solar Dynamics Observatory (SDO), which will take images of the Sun that are 10 times clearer than the most advanced televisions available.
The Rutherford Appleton Laboratory helped to make the high-tech cameras that will capture images of the solar flares (太阳耀斑) and explosions as they occur.
Professor Richard Hold away, the lab's director, said that the SDO should be able to provide early warning of a solar flare or explosion big enough to affect satellite communications on Earth "If we have advance warning, we'll be able to reduce the damage. What you don't want is things switching off for a week with no idea of what's caused the problem," he said. The phrase "communications blackout" in paragraph 1 most probably refers to _______during the 2012 Olympics.
| A．the extinguishing of the Olympic torch |
| B．the collapse of broadcasting systems |
| C．the transportation breakdown in London |
| D．the destruction of weather satellites |
What can be inferred about the solar activity described in the passage?
| A．The most fatal matter from the corona falls onto Earth. |
| B．The solar storm peak occurs in the middle of each cycle. |
| C．It takes several seconds for the charged matter to reach Earth. |
| D．The number of sunspots declines after coronal mass ejections. |
According to the passage, NASA will launch a satellite to _________.
| A．take images of the solar system |
| B．provide early warning of thunderstorms |
| C．keep track of solar activities |
| D．improve the communications on Earth |
Which of the following might be the best title of the passage?
| A．Solar Storms: An Invisible Killer |
| B．Solar Storms: Earth Environment in Danger |
| C．Solar Storms: Threatening the Human Race |
| D．Solar Storms: Human Activities to Be Troubled |
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