56．What was Backerster’s discovery?

　　　 A．Plants carry galvanometer.

　　　 B．It is possible to measure a small electrical charge with a small piece equipment called “galvanometer”

　　　 C．The small electrical charge on the leaves of the other plant can change if he destroyed the leaves on one of the two plants.

　　　 D．Humans have a similar field which can charge when we are shocked or frightened as plant.

55．What unusual phenomenon worries the scientists?

　　　 A．In summer the ice of the Arctic loses faster.

　　　 B．The ice covering the Arctic decreases even in winter.

　　　 C．The ice of the Arctic increases less than in the past.

　　　 D．The changes in the Arctic are more serious.

E

People who studied plants have found that plants carry a small electrical charge(电荷). It is possible to measure this charge with a small piece of equipment called “galvanometer”. The galvanometer is placed on a leaf of the plant, and it records any changes in the electrical field of the leaf. Humans have a similar field which can charge when we are shocked for frightened.

A man called Backster used a galvanometer for his studies of plants and was very surprised at his results. He found that if he had two or more plants in a room and he began to destroy one of them－perhaps by pulling off its leaves or by pulling it out of its pot－then the galvanometer on the leaves of the other plants showed a change in the electrical field. It seemed as if the plants were signaling a feeling of shock. This happened not only when Backster started to destroy plants, but also when he destroyed other living things such as insects.

Backster said that the plants also knew if someone had destroyed a living thing some distance away, because they signals when a man who had just cut down a tree entered the room.

Another scientist, named Sauvin, achieved similar results to Backater’s. he kept galvaometers fixed to his plants all the time and checked regularly to see what were sending. In this way, he found that the plants were sending out signals at the exact times when they felt strong, pleasure or pain. In fact, Sauvin could cause a change in the electrical field of his plants over a distance of a few miles simply by thinking about them.

54．The main idea of the fifth paragraph probably is ___________.

　　　 A．to explain the poles are cold and remote

　　　 B．to show the Arctic is more important

　　　 C．to tell readers the differences of the two poles

　　　 D．to stress the Antarctic is more remarkable

53．What is the main factor that has caused the changes of the poles?

　　　 A．The increasing number of animals.

　　　 B．The development of the poles.

　　　 C．The melting of the poles.

　　　 D．The rising temperature.

52．The goal of the International Polar Year is __________.

　　　 A．to make it clear that the poles have much to do with a healthy earth

　　　 B．to provide practical theory to further develop this distant area

　　　 C．to call on as many scientists as possible to do research on the poles

　　　 D．to discover more mysteries unknown to man

51．Which of the following might be the best tile of the passage?

　　　 A．Earth’s Poles Interest Scientists

　　　 B．The Animals of Earth’s Poles

　　　 C．Earth’s Poles in Danger

　　　 D．The Discoveries of Earth’s Poles

50．The passage is mainly about　　　　 .

A．a cheap way to get energy

B．the location of recycling plants

C．new ways of recycling wastes

D．the probability of city environment

D

The North and South poles are remote and freezing places that receive lots of animal visitors but few human tourists.

But even if you never plan to visit the polar bears in the north or penguins in the south, now is a perfect time to start thinking about them. That’s because 2007 marks the beginning of the International Polar Year (IPY), a two-year-old activity of science projects that aim to show how important the poles are to the health of our planet. During the IPY, which will last until March 2009, thousands of researchers from more than 60 countries will conduct more than 200 projects and expeditions to both the top and bottom of the world.

In recent years, the polar regions have begun to change severely as a result of global warming. Temperatures there are rising faster than anywhere else on Earth. As a result, the ice and snow in these regions are melting at record-setting rates. One result is that sea levels are rising around the world, putting animals and people at risk.

Only by studying the poles, say IPY researchers, can we find ways to protect them and ourselves.

Both the Arctic and the Antarctic and cold and remote, but the two regions have important differences. For one thing, the Arctic is an ice-covered ocean surrounded by land. The Antarctic, on the other hand, is a continent of ice-covered land surrounded by water.

Most polar studies have focused on the Arctic, and that is where scientists have observed the most remarkable changes in the ice. During a typical year, Arctic ice expands in the winter and shrinks in the summer. But recently, the amount of ice covering the ocean has been steadily dropping in both seasons.

49．The first full-scale huge recycling plants 　　　　.

　　 A．began to operate fifteen years ago

　　 B．will probably take less than fifteen years to build

　　 C．will be built for fifteen years

　　 D．will probably be in operation in fifteen years

48．What’s the main reason for big cities to build their own recycling plants?

A．To deal with wastes in a better way.

B．To protect the environment from pollution.

C．To get raw materials locally.

D．To get big profits from those plants.

47．What is NOT mentioned as a part of the recycling process described in paragraph 3?

A．Breaking up whatever is breakable.

B．Sharpening metal bars.

C．Separating light elements from the heavy ones.

D．Sorting out small pieces of metal.