.

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.

 

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第二节(共5小题;每小题 2分,满分10分)

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Although many Chinese students say their knowledge of English grammar is good, most would admit that their spoken English is poor. 61     However, their spoken English does not have to remain poor I would suggest that there may be some reasons for their problems with spoken English.

First,  62    Obviously the better answer is to expand their vocabulary. However, you can speak with a limited vocabulary if your attitude is positive. Others will follow you as long as you use the words that you know.

Second, 63      Sometimes they make mistakes when they are speaking because they are shy and nervous. Yet students should remember that their goal should be FLUENCY NOT ACCURACY. You want to get your message across, to talk to someone in English, as quickly and as well as you can, even though sometimes you may use a wrong word or tense, but it doesn't matter because the person you are speaking to will understand you and make allowance for any mistakes he hears.

The third,   64    You have one mouth but two ears! All that hearing is necessary for you to start speaking.

Fourth,    65      Instead of actively seeking out opportunities to improve their spoken English, they passively wait for speaking opportunities to come to them and wonder why their spoken English always remains poor. If you have this proactive outlook, then you will see English opportunities wherever you go.

A not enough attention is paid to listening.

B they fail to find suitable words to express themselves because of  limited vocabulary.

C most Chinese students are not active language learners.

D They are so stupid that they cannot finish their necessary homework in time.

E Whenever I speak to Chinese students they always say, "My spoken English is poor."

F it is no use crying over spilt milk.

G they are afraid of making mistake .

 

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