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 life.

Venter and his researchers made a breakthrough this August. They successfully moved the DNA of one type of bacteria(细菌) to a yeast(酵母) cell, 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 called Mycoplasma mycoides. The team took the bacteria’s genes and put them into a yeast cell.

Putting the 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.

“If 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 from 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 results.

1.Craig Venter and his team are working to ______.

A.create a new animal

B.clone a new species

C.produce the first artificial bacteria

D.develop a new system

2.Which of the following is the right order of the experiment?

a. A gene was removed and put into a host bacteria cell.

b. The genes were put into a yeast cell.

c. The cell produced new healthy bacteria.

d. The genes were changed.

e. Some genes were taken out of Mycoplasma mycoides.

A.d-e-a-c-b                              B.e-b-d-a-c

C.a-d-e-c-b                              D.b-e-d-c-a

3.According to the passage, complex artificial bacteria, which will follow the first simple man-made bacteria, are intended to ______.

A.cure deadly diseases

B.prepare the Earth for natural disasters

C.prove that the technology can work

D.improve the earth’s environment

4.We can learn from the passage that ______.

A.Venter and his team are the only scientists trying to create artificial life

B.The experiment was based on research into different kinds of life on Earth

C.A new type of bacteria was created in January

D.All scientists are not in favor of the research

 

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。

Competitors who wear red win more than those that are dressed in any other color, according to a study in Germany.

1

Experts believe that red could make individuals and teams feel more confident as well as being perceived by others as more aggressive.

2 On the other hand, the results could suggest that the success of those teams has given those that wear the red color more confidence.

The study, by German sports psychologists at the University of Munster, was reported in New Scientist magazine. They showed video recordings of taekwondo(跆拳道) matches to 42 experienced referees(裁判). One fighter wore blue and the other wore red.

They then showed them the same recordings but digitally manipulated(操纵) the clothing to exchange the colors. 3

“If one competitor is strong and the other is weak, it won’t change the outcome of the fight,” said Norbert Hagemann, who led the study. “4

In 2004 scientists at Durham University also looked at how color influenced sporting competitiveness. They analyzed Olympic contest sports such as boxing, tawkwondo, and freestyle wrestling and found that nearly 55 percent of which were won by the competitor in red.

5” said Robert Burton, one of the researchers.

A.It is the color of fire and is often associated with energy, danger, strength, power, and determination.

B.The fighters wearing red were given an average of 13 percent more points than when they wore blue.

C.The study shows that football shirts from worldwide teams such as Arsenal, Liverpool, sell successfully.

D.It is reasonable that wearing red makes individuals feel more confident, although this hasn’t yet been tested.

E. Researchers found that those who wear red tops, jackets or clothing score 10 percent more in any competition than if they were in another color.

F. The findings could explain why Manchester United, Liverpool and Arsenal have been so successful.

G. But the closer the levels, the easier it is for the color to tip the scale

 

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