Of all the reasons, cloning for medical purposes has the most potential to benefit large numbers of people. How might cloning be used in medicine?
Much of what researchers learn about human disease comes from studying animal models such as mice. Often, animal models are genetically engineered to carry disease-causing mutations (变异) in their genes. Creating these transgenic animals is a time-intensive process that requires trial-and-error and several generations of breeding. Cloning technologies might reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study.
Stem cells are the body's building blocks, responsible for developing, maintaining and repairing the body throughout life. As a result, they might be used to repair damaged or diseased organs and tissues. Researchers are currently looking toward cloning as a way to create genetically defined human stem cells for research and medical purposes. To see how this is done, see Creating Stem Cells for Research, a component of the Stem Cells in the Spotlight module.
Farm animals such as cows, sheep and goats are currently being genetically engineered to produce drugs or proteins that are useful in medicine. Just like creating animal models of disease, cloning might be a faster way to produce large herds of genetically engineered animals. Find out more about this research in the feature article Pharming for Farmaceuticals.
Have you seen Jurassic Park? In this feature film, scientists use DNA preserved for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and fiercer than expected.
In reality? Probably not. It's not likely that dinosaur DNA could survive undamaged for such a long time. However, scientists have tried to clone species that became extinct more recently, using DNA from well-preserved tissue samples.
To clone or not to clone: that is the question. The prospect of cloning humans is highly controversial and raises a number of ethical, legal and social challenges that need to be considered. Of all the reason of cloning, which do people think is the most benefit to people?
| A．Medicine purpose. | B．protecting endangered animal |
| C．Cloning for some families. | D．Purifying human beings |
By the passage we can infer that the side effect people would research human disease using animal models is __________.
| A．the sample is not the same with human |
| B．the sample has less function than human |
| C．the sample often carries disease in the genes |
| D．the results can't adapt to human |
What function do stem cells play in body?
| A．Breeding. | B．Repairing. | C．Replacing. | D．Reproducing. |
According to the passage, which statement of the following is not right?
| A．Cloning animals have achieved now. |
| B．By cloning people can cure some deadly diseases. |
| C．Dinosaurs in the future film are smarter. |
| D．Cloning can bring human only happiness. |
The title of this passage probably is __________.
| A．Why clone? | B．The benefit of cloning. |
| C．Cloned animals. | D．Cloning in the future. |
Travel is fun and exciting, but it’s not if you get sick. You may think, “Not me, I won’t get sick in my holiday.” But, for many people, that is what happens.
Of course you don’t want to spend your holiday sick in bed. So what can you do to stay in good health? There are three things you should remember when you travel: relax, sleep, and eat well.
A holiday must be a time for relaxing. But very often it is not. Think about what you do when you are a traveller. There are many places to visit: museums, shops, parks, churches. You may spend most days walking around these places. This can be very tiring. You may have a terrible headache after a few hours. If this is the way you feel, you should take a rest. Don’t ask your body to do too much. A tired body means a weak body. And a weak body gets sick easily. So sit down for a few hours in a nice place. In good weather, look for a quiet park bench(石凳). Or you can stop at a cafe. You can learn a lot by watching people while you rest.
Sleep is also important. If you want to stay healthy, you need to get enough sleep. You may have trouble sleeping at night when you travel. There may be too many noises in your hotel or the bed may be uncomfortable. If this is true, don’t be afraid to change rooms or hotels. Or you may get enough sleep for another reason. You may want to stay out late at night. In many cities, the nightlife can be very exciting. Then you should plan to sleep for an hour during the day. The extra(额外) hour can make a big difference。
Finally, if you want to stay healthy, you must eat the right kinds of foods but you need to be careful about how much you eat. Lots of food is not good for you.
So, remember this, if you want to enjoy your holiday, take care of yourself. Give your body some rest. Get enough sleep and eat good, healthy food.This passage is about ______
| A．how to stay healthy when you travel |
| B．how exciting travel is |
| C．relaxing when you travel |
| D．what you eat when you travel |
Travel is ______
| A．the best way to relax | B．very tiring |
| C．never any fun | D．unhealthy |
Your body needs sleep to_____
| A．enjoy the nightlife | B．stay strong and healthy |
| C．change hotels | D．learn a lot about a new place. |
Why can you have a terrible headache while visiting these places?
| A．Because you don’t like these places |
| B．Because some place makes you feel headache |
| C．Because you feel boring to visit these places. |
| D．Because there are so many places to visit. |
You can change your rooms or hotels, if______.
| A．you want to stay out late at night |
| B．you want to eat different food |
| C．your hotel is noisy |
| D．you can’t get on well with the manager in the hotel |
Saturday, March 24th
We have arrived in the hot, wet city of Bangkok. This is our first trip to Thailand（泰国）. All the different smells make us want to try the food. We are going to eat something special for dinner tonight. The hotel we are staying in is cheap, and very clean. We plan to stay here for a few days, visit some places in the city, and then travel to Chiang Mai in the North.
Tuesday, March 27th
Bangkok is wonderful and surprising. The places are interesting. We visited the famous market which was on water, and saw a lot of fruits and vegetables. Everything is so colorful, and we have taken hundreds of photos already! Later today we will leave for Chiang Mai. We will take the train north, stay in Chiang Mai for two days, and then catch a bus to Chiang Rai.
Friday, March 30th
Our trip to Chiang Rai was long and boring. We visited a small village in the mountains. The village people here love the quiet life—no computers or phones. They are the kindest people I have ever met. They always smile and say “hello”. Kathy and I can only speak a few words of Thai, so smiling is the best way to show our kindness. I feel good here and hope to be able to come back next year.The diaries above show the writer’s ______ days in Thailand.
| A．3 | B．8 | C．15 | D．7 |
It seems that visitors _________ in Bangkok.
| A．often feel hungry | B．can have a good time |
| C．can’t take any photos | D．feel a little bored |
Which of the following is TRUE?
| A．The writer left Chiang Mai for Chiang Rai by bus. |
| B．Chiang Mai is a beautiful city in the south of Thailand. |
| C．The writer is traveling alone in Thailand. |
| D．The writer will take a bus to Chiang Mai. |
The people in the village _______.
| A．are friendly to others | B．like to speak English |
| C．hope to live in the cities | D．live a very busy life |
What is the best title（标题）for the whole diary?
| A．My First Travel | B．Traveling in Thailand |
| C． The Outside World | D．My Trip to Chiang Mai |
In the north of Scotland there is a lake called Loch Ness. It is the biggest lake in Britain. It is over thirty kilometres long and in places nearly 300 meters deep. It is cold and dark and not many people went there until after 1930. Then a road was made around the lake. Holiday makers began to use the road, and this was when the stories began.
Someone said that he had seen a monster in the lake. He said it was twelve meters long. It had a long neck and a small head. Then someone else said he had seen it. Others said the same thing and in 1933 a London doctor took a photo. It looked like a monster with a long neck and a thick body but the photo was not dear. The newspapers printed the picture and called it the Loch Ness monster, or "Nessie".
Then the argument began. Some people, however, were certain there was something living in the lake. Others said there was nothing there.
In 1961, a lot of people joined together to make a real effort to see and photograph the monster if there was one! Several times people thought they saw something but after ten years there was still no real proof.
Later underwater television cameras were used, but no one found any real proof. However, they did find something interesting: a huge underwater cave. It was big enough to be home of a monster, but of course, this was not a proof.
In 1975, however, some American scientists formed a search group. They used an underwater camera. It took pictures every seventy seconds. Some of the pictures seemed to show a red-brown creature. Its body was about four meters long and had a very ugly head on the end of a four meter neck. Many people then began to believe in the monster. But even today we can not be certain.Before 1930, ____.
| A．few people went to Loch Ness Lake |
| B．many people had been there |
| C．nobody went to the lake |
| D．nobody knew about the lake |
What did the monster look like?
| A．It looked like a horse. |
| B．It was a creature with a long neck and a small head. |
| C．It looked beautiful. |
| D．It was tiny and pretty. |
Who first took a photo of the monster?
| A．An American |
| B．A television camera |
| C．A holiday-maker |
| D．A doctor from London |
A search group formed by some American scientists.
| A．found the monster itself |
| B．found a huge cave under water |
| C．believed that there wasn't any monster at all |
| D．took some pictures which seemed to show a monster |
Far from the land of Antarctica, a huge shelf of ice meets the ocean. At the underside of the shelf there lives a small fish, the Antarctic cod.
For forty years scientists have been curious about that fish. How does it live where most fish would freeze to death? It must have some secret. The Antarctic is not a comfortable place to work and research has been slow. Now it seems we have an answer.
Research was begun by cutting holes in the ice and catching the fish. Scientists studied the fish’s blood and measured its freezing point.
The fish were taken from seawater that had a temperature of -1.88℃ and many tiny pieces of ice floating in it. The blood of the fish did not begin to freeze until its temperature was lowered to -2.05℃. That small difference is enough for the fish to live at the freezing temperature of the ice-salt mixture.
The scientists’ next research job was clear: Find out what in the fish’s blood kept it from freezing. Their search led to some really strange thing made up of a protein never before seen in the blood of a fish. When it was removed, the blood froze at seawater temperature. When it was put back, the blood again had its antifreeze quality and a lowered freezing point.
Study showed that it is an unusual kind of protein. It has many small sugar molecules held in special positions within each big protein molecule. Because of its sugar content, it is called a glycoprotein. So it has come to be called the antifreeze fish glycoprotein. Or AFGP.What is the text mainly about?
| A．The terrible conditions in the Antarctic. |
| B．A special fish living in freezing waters. |
| C．The ice shelf around Antarctica. |
| D．Protection of the Antarctic cod. |
Why can the Antarctic cod live at the freezing temperature?
| A．The seawater has a temperature of -1.88℃. |
| B．It loves to live in the ice-salt mixture. |
| C．A special protein keeps it from freezing. |
| D．Its blood has a temperature lower than -2.05℃. |
What does the underlined word “it” in Paragraph 5 refer to?
| A．A type of ice-salt mixture. | B．A newly found protein. |
| C．Fish blood. | D．Sugar molecule. |
What does “glyco-” in the underlined word “glycoprotein” in the last paragraph mean?
| A．sugar | B．ice |
| C．blood | D．molecule |
May : Happenings from the past
May 5,1884
Isaac Murphy , son of a slave and perhaps the greatest horse rider in American history , rides Buchanan to win his first Kentucky Derby . He becomes the first rider ever to win the race three times .
May 9 , 1754
Benjamin Franklin’s Pennsylvania Gazette produces perhaps the first American political cartoon （漫画）, showing a snake cut in pieces, with the words “ Join or Die” printed under the picture.
May 11,1934
The first great dust storm of the Great Plains Dust Bowl , the result of years of drought，blows topsoil all the way to New York City and Washington , D.C. .
May 19, 1994
Jacqueline Lee Bouvier Kennedy Onassis , former first lady and one of the most famous people of the 1960s , died of cancer in New York City at the age of 64 .
May 24, 1844
Samuel F.B. Morsr taps out the first message , “ What Hath God Wrought ,” over the experimental long-distance telegraph line which runs from Washington, D.C. , to Baltimeore , Md .We know from the text that Buchanan is_____________.
| A．Isaac”s father |
| B．a winning horse |
| C．a slave taking care if horses |
| D．the first racing horse in Kentucky |
What is the title of the first American political cartoon ?
| A．Join or Die | B．Pennsylvania Gazette |
| C．What Hath God Wrought | D．Kentucky Derby |
In which year did the former first lady Jacqueline die ?
| A．1934 | B．1960 |
| C．1964 | D．1994 |
Which of the following places has to do with the first telegram in history ?
A. Washington , D. C. B. New York City
C. Kentucky. D. Pennsylvania