题目内容

Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday.

Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights.

“Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal.

They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space.

The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added.

Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream.

The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth.

1.French scientists did their research on Russian astronauts, because _______.

A. they only cared for the Russian astronauts   

B. they were not interested in their own astronauts

C. the Russian government invited them to do their research  

D. the Russian astronauts worked in space for a long time

2. Scientists have found that _______.

A. the BMD loss may cause serious illness to astronauts

B. the BMD loss may cause some change in astronauts’ bodies

C. astronauts shouldn’t care about the BMD loss

D. astronauts should take some calcium before space travel

3. What cause the BMD loss to astronauts, according to this passage?

A. The food they eat in space.          B. The drinks they take in space.

C. The temperature in space.            D. The gravity in space.

4.In the third paragraph, the word “striking” means ______.

A. unusual      B. simple           C. weak         D. slow

 

【答案】

 

1.D

2.B

3.D

4.A

【解析】略

 

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Another man-made wonder of the United States was built long before the nation was established. About 900 years ago, the Ancestral Puebloan people built villages high in the walls of canyons in Colorado, where 600 cliff dwellings are now part of the Mesa Verde National Park.     

Visitors can stand at the top of the mesas and look into the dwellings almost hidden in openings of the rock walls. The Puebloan people cut small steps into the rock, which connected buildings containing hundreds of rooms.

The rock walls have protected the buildings from severe weather in the area; therefore, they remain mostly unchanged in the hundreds of years since they were built.

Our final man-made wonder is in the northwestern city of Seattle, Washington. The Space Needle was built as the central structure for the 1962 World's Fair.           

The 184-meter-tall structure was designed by Edward Carlson, which has a wide base on the ground, with its middle narrow and a large ring-like structure on top. The structure was meant to look like a "flying saucer," a vehicle that was popular in science fiction space travel stories.  The saucer includes an observation area and eating place. The restaurant slowly turns to provide visitors with a 360 degree view of Seattle.

The Space Needle, only costing about $4,500,000, was not very costly, and was designed and completed in about a year and opened on the first day of the World's Fair.

Today, the Space Needle is the most popular place for visitors to Seattle. And it remains the internationally known symbol of the city.

What the passage before this one can be about?

A. Some natural wonders in the world.

B. Sightseeing in the US.

C. Some other artificial wonders in the US.

D. American geography.

What does the underlined word “dwelling” mean?

       A. village                     B. house                C. canyon              D. step

Which of the following descriptions about the Space Needle is TRUE?

       A. It is a man-made wonder in Washington, D.C..

       B. Edward Carlson built the structure.

       C. It has a ring-like structure on top.

       D. It remains the internationally known symbol of the US.

What is the passage mainly about?

       A. Visiting the US                B. Man-made wonders in the US

       C. Wonders in the world              D. Famous places in the US

Have you ever dreamed of visiting a planet in the Milk Way? While the trip sounds exciting, it would take years and years to reach your destination. So in the future, bedtime for astronauts may be more than a few hours of regular shut-eye. They would have to sleep for years.

European researchers are now conducting hibernation experiments. The study may help them understand whether humans could ever sleep through the years it would take for a space flight to distant planets. "If there was an effective technology, it could make deep-space travel a reality," said Mark Ayre of the European Space Agency last month.

What seems like science fiction is not completely unlikely. Researchers have been able to use chemicals to put living cells into a sleep-like state where they don't age. They have now moved on to small, non-hibernating mammals like rats. The results will be out by the end of 2004.

A major challenge is the fact that cells can be very simple systems, whereas body organs are far more complex.

"It's like moving from a simple Apple computer to a supercomputer," said Marco Biggiogera, a hibernation researcher at Italy's University of Pavia.

Just like bears and frogs, the hibernation of human beings would cause a person's metabolism (新陈代谢) to lower so they would need less energy.

Medical research, however, is just half of a space flight hibernation system.

There is the challenge of designing a suitable protective shelter. Such a shelter would provide the proper environment for hibernation, such as the proper temperature. It would also have to monitor (监控) life functions and serve the physiological needs of the hibernator.

According to Ayre, the six-person Human Outer Planets Exploration Mission to Jupiter's moon (木星的卫星) Callisto, could be an opportunity to use human hibernation. The mission aims to send six humans on a five-year flight to Callisto, where they will spend 30 days, in 2045.

9. European researchers are conducting hibernation experiments to ________.

A. ensure astronauts to get a complete sleep  B. find the secret of some creatures

C. make preparations for the journey to Jupiter’s moon Callisto

D. know if man can sleep for years

10. The sentence “What seems like science fiction is not completely unlikely” means ________.

A. Science fiction is people’s imagination.

B. Science fiction is imaginative, but it can be realized.

C. Things seem impossible may come true.

D. Things described in science fiction are sure to become true.

11. The passage is implied but doesn’t states that ________.

A. putting living cells into a sleep-like state is full of failure

B. Biggiogera is confident with the experiment

C. human’s hibernation needs no energy

D. medical research is the key to space flight hibernation system

12. By designing a suitable protective shelter, astronauts can ________.

A. have a good hibernation        B. lessen the pressure of traveling in space

C. feed themselves in spaceship    D. moinitor their body changes

13. What’s the best title for the passage?

A. Six humans to fly to Callisto  B. Human hibernation improves health

C. Space travel attracts people   D. Deep sleep for deep space travel

As in the field of space travel, new technologies continue to appear in undersea exploration. They share a number of similarities with each other — as well as some important differences.
Manned submersibles (潜水器), like spaceships, must maintain living conditions in an unnatural environment. While a spaceship must simply be sealed against the vacuum space, a submersible must be able to bear extreme pressure if it is not to break up in deep water.
In exploring space, unmanned vehicles were employed before astronauts. In undersea exploration, on the other hand, men paved the way, and only recently have unmanned remote-operated vehicles (ROVs) been put to use.
One reason for this is that communicating with vehicles in orbit is much easier than talking to those underwater. A vacuum is an ideal medium for radio communications, but underwater communications are limited to much slower sound waves. Thus, most undersea vehicles — particularly ROVs — operate at the end of long ropes.(电缆终端)
For a similar reason, knowing where you are undersea is much more difficult than in space. A spaceship’s position can be located by following its radio signal, or by using telescopes and radar. For an undersea vehicle, however, a special network of sonar (声纳系统)devices must be laid out in advance on the ocean floor in the area of a dive to locate the vehicle’s position.
Though undersea exploration is more challenging than outer space in a number of respects, it has a distinct advantage: going to the ocean depths doesn’t require the power necessary to escape Earth’s gravity. Thus, it remains far less expensive.
【小题1】The purpose of the passage is ______.

A.to persuade you to explore the depths of the ocean
B.to stress the importance of the undersea exploration
C.to make you believe that the undersea exploration is better
D.to tell some differences between two kinds of explorations
【小题2】 By saying “men paved the way” in Paragraph 2 the author means that in undersea exploration ______.
A.unmanned vehicles were used in the beginning
B.men covered the ocean floor with stones and bricks
C.manned vehicles were employed before unmanned ones
D.men invented unmanned remote-operated vehicles in the past
【小题3】The sonar devices must be placed ______.
A.from time to time
B.after the undersea vehicles dive
C.before the undersea vehicles dive
D.when the undersea vehicles are diving
【小题4】What can we infer from the passage?
A.Submersibles usually break up in deep water.
B.Undersea vehicles can receive signals immediately.
C.Going to space needs power to escape the gravity.
D.Radio communications are quite difficult in a vacuum.

The space shuttle Discovery has had a long and busy career. For 27 years, it has worked for NASA, carrying astronauts to space and back on 39 missions. On March 9, 2011, after returning from its final voyage, the world’s most traveled spaceship was retired.
A crowd of shuttle workers, reporters and schoolchildren waited to greet Discovery at Kennedy Space Center in Cape Canaveral, Florida. Three minutes before noon, they watched as the shuttle appeared in the sky and made one last touchdown. “For the final time: wheels stop,” Discovery’s commander Steven Lindsey said when the shuttle rolled to a stop.
Discovery’s final trip was to the International Space Station (ISS), a giant space lab in the sky. Discovery’s crew took care of the last U.S. construction project at ISS. They delivered 10 tons of supplies for the ISS. The six-person crew also dropped off an unusual companion for ISS’s researchers: a human-like robot named Robonaut 2. Astronauts will assemble(组装)R2 at the ISS over several months.
Now, NASA is winding down its shuttle programme. NASA is to begin work on new spaceships that can travel longer distances. Discovery’s retirement is the first of three. Endeavor, another shuttle, is scheduled to make its final voyage soon. And Atlantis’s last trip is planned for the end of June.
Museums across the country have requested the retired shuttles. The Smithsonian’s Air and Space Museum, in Washington, D.C., was the lucky recipient(接收者)of Discovery. The museum’s collection contains hundreds of NASA artifacts.
Where will the other shuttles go? You’ll have to wait to find out. NASA will announce its decision on April 12, the 30th anniversary of the first space shuttle launching. Stay tuned!
【小题1】As part of the final mission, Discovery’s crew___________.

A.carried researches to space
B.assembled the Robonaut 2 at the ISS
C.brought supplies to the ISS
D.went on a spacewalk
【小题2】The underlined phrase “winding down” in Paragraph 4 probably means _________.
A.improvingB.endingC.changingD.testing
【小题3】What can we infer from the text?
A.Discovery completed 39 missions during its two decades of space travel.
B.The ISS is a big project and six researchers live on the station.
C.American space exploration will focus on longer missions.
D.The shuttles Endeavor and Atlantis will make their last missions next month.
【小题4】According to the text, we can learn about ___________.
A.people’s opinions of Discovery’s retirement
B.the government’s concern about the shuttles’ future
C.the shuttles’ final homes after retirement
D.museums’ great interest in the retired shuttles

The US space agency NASA is looking for people to go to Mars, and stay there. This attractive career is for people who want a huge change of scenery and planet. The project is called the Hundred Years Starship, which aims to colonize (开拓殖民地) other lands such as the red planet Mars.

Settlers would travel to the red planet and live there forever. NASA says it would be too expensive to bring humans back to Earth. The space agency can afford, however, to send supplies to the astronaut pioneers from Earth. Astronauts would be landed on the planet's surface and would never be able to return home due to the cost.

NASA has started the project with $1.6 million, and hopes to attract investment from space-living billionaires. Google co-founder Larry Page told NASA he would be interested if the cost of a one-way ticket can go down from $10 billion to $2 billion.

The journey to Mars could take 4 months. Setting on the red planet would be extremely dangerous, especially given the freezing temperatures there. The thin atmosphere would be another problem as it is mostly carbon dioxide, so oxygen supplies are a must. A director in NASA said that he believed the trip might start with visiting Mars's moons first. He claimed that humans could be on Mars's moons by 2030.

Many scientists think colonizing space is absolutely necessary. Steven Hawking believes we must move to other planets to survive as a species. He said: “Once we spread out into space and establish independent colonies, our future should be safe.” Scientists Dirk' Schulze-Makuch and Paul Davies also call it a “desirable goal”, though there surely are huge risks to explore new lands.

1.Which of the following is TRUE about the Hundred Years Starship?

A.It has cost NASA around $10 billion.

B.It is expected to be conducted on Mars in 2030.

C.It aims to explore new lands in the universe.

D.It is a project first raise by Steven Hawking.

2.We can infer from the passage that Google co-founder Larry Page _______.

A.used to be an astronaut                  B.is no longer rich now

C.is a fan of space travel                    D.is a generous man

3.What would be the best title for the passage?

A.One-way trip to Mars

B.Mars's another moon is found.

C.Human landing on Mars.

D.NASA's first cooperation with Google.

 

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