.
Scientists have not come close to understanding all the different kinds of life on the planet, but US researcher Craig Venter is already working on creating the first artificial(人造的)life.
Venter and his researchers made a breakthrough late last month, They successfully moved the DNA of one type of bacteria(细菌) to a yeast cell(酵母), changed it, then put it into another bacterial cell.
“Bacteria have systems that protect them from foreign DNA” Venter explained to the BBC, In the experiment, the team managed to block this system.
The experiment was performed on a simple type of bacteria celled mycoplasma mycoides. The team took the bacteria’s genes and put them into a yeast cell.
Putting a DNA in a yeast cell allowed the team to change the genes in this case, taking out a gene that was not necessary for the bacteria to live.
They then put the gene into a host bacteria cell. The cell went on to divide normally, producing new healthy bacteria.
In January, the team created artificial genes of a new type of bacteria. Their next goal is to put the artificial DNA into a host cell to create a new species, according to a report in Science magazine.
“lf we don’t make any errors, I think it should work and we should have the first artificial species by the end of the year.” Venter said in the report.
The first artificial life form is likely to be a simple man-made bacteria, to prove that the technology can work.. But that form will be followed by more complex bacteria that turn coal into cleaner natural gas, or algae that can take in carbon dioxide and change it into fuel.
Many scientists think it’s good news to have this artificial life, but others are worried that the technology to create new organisms might end up in the wrong hands, with dangerous result.
57.Which of the following is true according to the text ?
A Bacteria have systems that protect them from yeast cell.
B If we put a gene into a host bacteria cell,the cell will not go on to divide as usual.
C Venter and his researchers completely achieved all their goals.
D All the scientists didn’t agree to this artificial life.
58. What can we learn from the underlined sentences?
A. Venter and his researchers had succeeded in this project.
B. Venter predicted that they would make errors in the future,so he decided to give it up.
C. Venter would go on the study and he was full of confidence.
D. Venter was a clearer man but a little shy.
59. Which of the following shows the order of the passage ?
1.change the genes
2. put the gene into a host bacteria cell
3. moved the DNA of one type of bacteria to a yeast cell
4. The cell went on to divide normally
5. put it into another bacteria cell
A. 3-5-1-4-2 . B. 3-5-1-2-4 C. 4-2-5-1-3 D. 2-3-5-1-4
60.What will be mentioned in the next paragraph?
A. The wrong hands that created by the artificial life.
B. The advantages and disadvantages about the artificial life.
C. The future about this project.
D. The author’s attitude.
The scene in the Hollywood movie The Day After Tomorrow, when global warming could soon turn the global climate into a new ice age, may never occur, according to a new research.
The next ice age could be 15,000 years away, say European scientists who last month announced a continuous record of 740,000 years of climate data obtained from the Antarctic ice.
Scientists from 10 nations have now almost completely drilled through a 3,000-meter depth of ice high in the Antarctic mainland. They figure out that the area, where summer temperatures can fall to – 40℃, has at least 900,000 years of snowfalls, kept as neatly as the growth rings of a tree. And the ice and air caught in each layer(层) have begun to answer questions about the climates in the past..
The results show that there have been eight ice ages in the past 740, 000 years and eight warmer periods. And by comparing the pattern of global conditions today with those of the past, the researchers reported in Nature that the present warm period could last another 15, 000 years.
Research suggests that there is a very close connection between greenhouse gas levels and global average temperatures. It also shows that carbon dioxide (二氧化碳) levels are the highest for at least 440,000 years.
"If people say to you: ‘the greenhouse effect is a good thing because we would go into an ice age otherwise,’ our data say no, a new ice age is not hanging over our heads,” said Eric Wolff from the British Antarctic Survey. "Now we have eight examples of how the climate goes in and out of ice ages… and you can learn what the rules are that go into the climate models that tell us about the future."
Scientists found that whenever temperatures rose in the frozen record, so did carbon dioxide level. "In 440,000 years we have never seen greenhouse gas get as thick as it is today," said Dr Wolff.In drilling through the ice in Antarctica, scientists have found that______.
A.the lowest temperature there is – 40℃ |
B.the depth of ice is 3,000 meters |
C.the ice has existed for 15,000 years |
D.snowfalls are kept in certain patterns |
The information of the global climate conditions in the past can be obtained through______.
A.separating carbon dioxide from the air |
B.examining the growth rings of trees |
C.comparing temperatures in different areas |
D.studying the ice and air caught in each layer |
We can infer from Eric Wolff's words that_______.
A.there is something wrong with the data |
B.greenhouse effect is always a bad thing |
C.a new ice age will not come in the near future |
D.greenhouse gas will get thick in the future |
What would be the best title for the passage?
A.Research over the Antarctic area. |
B.Warm period to last about 15, 000 years. |
C.Report on the eight ice ages in the past. |
D.Hollywood movies and the global climate. |
Money is the root of all evil and new study claims there may be some truth behind the saying.Scientists at the University of California, Berkeley, US,announced on February 27 that rich people are more likely to do unethical (不道德的) things, such as lie or cheat, than poorer people.
The scientists did a series of eight experiments. They published their findings online in the Proceedings of the National Academy of Sciences (PNAS,《美国国家科学院院刊》).
They carried out the first two experiments from the sidewalk near Berkeley. They noted that drivers of newer and more expensive cars were more likely to cut in on other cars and pedestrians at crosswalks. Nearly 45 percent of people driving expensive cars ignored a pedestrian compared with only 30 percent of people driving more modest cars.
In another experiment, a group of college students was asked if they would do unethical things in various everyday situations. Examples included taking printer paper from work and not telling a salesperson when he or she gave back more change. Students from higher-class families were more likely to act dishonestly.
According to the scientists, rich people often think money can get them out of trouble. This makes them less afraid to take risks. It also means they care less about other people’s feelings.
Finally,it simply makes them greedier.“Higher wealth status seems to make you want even more,and that increased want leads you to bend the rules or break the rules to serve your self-interest,” said Paul Piff, leading scientist of the study.
Piff pointed out that the findings don’t mean that all rich people are untrustworthy or that all poor people are honest. He said the experiments were to show how people living in different social situations express their instincts and values in different ways.By saying “money is the root of all evil”,the author wants to ____________.
A.draw readers’ attention to the research |
B.1ink wealth with bad behavior |
C.show how the saying proves the findings |
D.defend rich people who do unethical things |
What makes rich people unethical according to the scientists?
a.they become more selfish b.they have more desires
c.they believe money talks d.they welcome risks
A.a、b | B.a、b、d |
C.b、c | D.a、b、c |
Why did the scientists do the experiments?
A.To show how social status affects people's ethics. |
B.To show people’s instincts and values in different ways. |
C.To test whether the saying “money is the root of all evil” is true. |
D.To show the difference between higher-class people and lower-class people. |
What does the article really want to show us?
A.Money is the root of all evil. |
B.The rich are more likely to act badly. |
C.The saying is unreasonable. |
D.All rich people are untrustworthy. |
Thousands of people began pouring into Pennsylvania from other states. They wanted to buy lottery tickets. The tickets cost only $ 0.9 each. But that small spending could bring them a reward of $ 90 million .That was the second largest lottery jackpot (积累奖金)in history.
More than 87 million tickets were bought for the Pennsylvania lottery drawing. Those who bought tickets had to choose seven numbers from 1 to 80.The chance of winning was one in 9.6 million, but that little chance certainly didn’t affect ticket sales. In the last few days before the drawing, tickets were sold at the unbelievable rate of 500 per second.
Experts say many people buy lottery tickets because they just want to have a piece of the action. Others say the lottery is a stock market for poor people. It allows them to dream about wealth they’ll probably never have.
But many people believe lotteries are no better than legalized gambling. Some critics note that most people who play are poor and may not be able to afford the tickets. There are also many addicts who take the game seriously. They may pour their life savings into lottery tickets. Some clubs have been formed to help them kick the habit.
Politicians like lotteries because they provide money that would otherwise have to come from new taxes. The profits from lotteries are usually used to pay for education or programs for senior citizens. But critics say this arrangement just allows states to legalize vice(恶习), under the name of social progress. Whether you regard stock lotteries right or not, you cannot refuse to accept their extreme popularity with many Americans.The main idea of the passage is that __________.
A.lotteries are of great benefit to everyone who buys them |
B.playing a lottery is just like investing in the stock market |
C.many people buy lottery tickets , but lotteries cause disagreement |
D.lotteries are nothing but legalized vice |
Which of the following is TRUE according to the passage?
A.Politicians like lotteries because they don’t have to pay extra taxes. |
B.The popularity of lotteries in America actually is social progress. |
C.Some critics don’t like lotteries because many poor people waste money on them. |
D.People love the lottery because it is a stock market. |
In just one hour in the last few days, the Pennsylvania lottery sold tickets totaling_______.
A.$ 1.62 million | B.$ 1.82 million |
C.$ 9.6 million | D.$ 87 million |
People who are addicted to playing lotteries should __________.
A.join a support group | B.kick the habit |
C.win the lottery | D.save every cent |
The arts, especially music, should be part of every school's lessons at every grade level. Students would be much smarter if they had some musical experience. They could improve their classroom skills, like paying attention and following directions. People develop all these skills when they learn music. Making music also lets children use their imagination. It provides students with a chance to try out their own ideas.
Music not only makes children better students, but also gives them something positive to do. In a music program, children can be part of a band instead of joining a gang(团伙). Parents can enjoy listening to their children's music instead of seeing them glued to a computer or TV screen. In a school band, students get to be part of a team. They can get along well with old friends and make new friends through music.
Music builds self-confidence, too. It gives children a sense of achievement and success. Making music is something for them to be proud of, and it lets kids practice performing in front of an audience. Music gives children an opportunity for self-expression, and that helps develop their self-confidence.
Once again, music is important because it can make children better students, give them something positive to do, and build their character. That is why music should be offered in every single grade in every school.According to the passage, music could make students smarter by __________.
A.improving their classroom skills and paying attention |
B.improving their classroom skills and imagination |
C.improving their attention, direction and imagination |
D.learning music, making music and trying out their own ideas |
What does the underlined phrase "glued to" in the second paragraph mean?
A.unwilling to turn on | B.always looking |
C.unwilling to leave | D.always playing |
The third paragraph mainly tells us that music could _______________.
A.give children self-expression and self-confidence |
B.bring to children achievement and success |
C.give children something to be proud of |
D.develop children's self-confidence |
What's the best title of this passage?
A.Music is a must as a course at school |
B.Music builds children's self-confidence |
C.Music makes students much smarter |
D.Learning music and making music |
The Healthy Habits Survey(调查) shows that only about one third of American seniors have correct habits. Here are some findings and expert advice.
1. How many times did you brush your teeth yesterday?
·Finding:A full 33% of seniors brush their teeth only once a day.
·Advice:Remove the 300 types of bacteria in your mouth each morning with a battery-operated toothbrush. Brush gently for 2 minutes, at least twice a day.
2.How many times did you wash your hands or bathe yesterday?
·Finding:Seniors, on average, bathe fewer than 3 days a week. And nearly 30% wash their hands only 4 times a day—half of the number doctors recommend.
·Advice:We touch our faces around 3,000 times a day—often inviting germs(病菌) to enter our mouth, nose, and eyes. So use toilet paper to avoid touching the door handle. And, most importantly, wash your hands often with hot running water and soap for 20 seconds.
3.How often do you think about fighting germs?
·Finding:Seniors are not fighting germs as well as they should.
·Advice:Be aware of germs. Do you know it is not your toilet but your kitchen sponge that can carry more germs than anything else? To kill these germs, keep your sponge in the microwave for 10 seconds.What is found out about American seniors?
A.Most of them have good habits. |
B.Nearly 30% of them bathe three days a week. |
C.All of them are fighting germs better than expected. |
D.About one third of them brush their teeth only once a day. |
Doctors suggest that people should wash their hands ________.
A.twice a day | B.three times a day |
C.four times a day | D.eight times a day |
Which of the following is true according to the text?
A.We should keep from touching our faces. |
B.There are less than 300 types of bacteria in the mouth. |
C.A kitchen sponge can carry more germs than a toilet. |
D.We should wash our hands before touching a door handle. |
The text probably comes from ________.
A.a guide book | B.a popular magazine |
C.a book review | D.an official document |