Bacteria do not develop at low temperature, so that food can be in cold storage. A. deserved B. reserved C. preserved D. conserved 题目和参考答案——青夏教育精英家教网—

题目内容

Bacteria do not develop at low temperature, so that food can be _______ in cold storage.

A. deserved B. reserved C. preserved D. conserved

解析:

preserve“保护，保存”，指安全地保藏或贮存水果、蔬菜、蛋类等。conserve“保存，保护”，尤指对自然资源的保护，避免浪费；reserve“保留，留存，贮留”；deserve“应受到，值得”。句意为：细菌在低温下不能繁殖，因此食品可以冷藏。

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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.
【小题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

【小题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

【小题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

【小题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

Few people ever took notice of Mr. Jimmy Tan whenever he entered a room. He was a shy, quiet and simple man who preferred to keep to himself in public. On the other hand, Mr. Thomas Kim, a fellow scientist, was a man everyone would notice on the streets. He wore bright outfits with huge flower prints, spoke with a booming voice, and his laughter could be heard from all corners of a room. In addition to the differences in their characters, Mr. Kim and Mr. Tan were also great rivals at work in the Institute of Future Science.

On Christmas Eve, everyone left work early to celebrate the special occasion, except for Mr. Tan and Mr. Kim. They were in their laboratory analyzing the results of their latest experiments. Mr. Tan realized that something special was taking place in his experiment —the bacteria he had cultured were growing extremely quickly under high pressure and at a very low temperature. After noting down the findings in his notebook, he left the room to prepare for another round of tests. Shortly after, Mr. Kim entered.

“Hey Jimmy,” Mr. Kim called out, “do you have an extra copy of the laboratory booking form?”

There was no reply, so Mr. Kim looked through Mr. Tan’s things. He soon found Mr. Tan's notebook and was horrified to see that Mr. Tan had managed to make one of the most important discoveries in modern science. He then looked into the deep-freeze cupboard where a dish containing the bacteria was kept. He put them into his pocket and returned to his own laboratory.

Mr. Tan came back an hour later to find his notebook and the dish missing. He knew that Mr. Kim had taken them and went to Mr. Kim's laboratory to find out. When he opened the door, he found Mr. Kim lying on the floor motionless. His face was pale and his skin had turned black. The deadly bacteria had been handled improperly. He shook his head and left.

1.From the first paragraph we know Mr. Kim was a quite person.

A．famous B．hardworking

C．wealthy D．outgoing

2.The underlined word "rivals" in the first paragraph is closest in meaning to .

A．enemies B．colleagues

C．competitors D．friends

3.What does the underlined word “them” refer to in the 4th paragraph?

A．the most important discoveries

B．the notebook and the dish

C．the cupboard and the bacteria

D．the dish and the bacteria

4.Which of the following is true according to the passage?

A．Mr. Kim was afraid Mr. Tan might succeed ahead of him.

B．Mr. Tan's bacteria grew very fast in a warm container.

C．Mr. Tan worked much harder than Mr. Kim.

D．Mr. Kim was so tired that he fell down into sleep.

5.What happened to Mr. Kim in the end?

A．He died on Christmas Eve.

B．He was arrested by the police.

C．He shared the success with Mr. Tan.

D．He succeeded ahead of Mr. Tan.

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

第三部分：阅读理解（共20小题；每小题2分，满分40分）

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A study finds that, contrary to many parents’ fears, owning cats or dogs does not increase a child’s risk of developing allergies, and in fact, may actually protect them. The study’s lead author, Dr. Dennis Ownby of the Medical College of Georgia, said that even he was “very surprised” by the results. Ownby and colleagues followed more than 470 children from birth to age 6 or 7, comparing those exposed to cats and dogs during their first years of life to those who were not.

By using skin-prick tests for detecting common allergies, the researchers found that, contrary to what many doctors had been taught for years, children who had lived with a pet were not at greater risk.

Even more remarkable, children who had two or more dogs or cats had an even greater reduction, up to 77 percent, in risk of allergies. Researchers suggest this protective effect may be the result of early exposure to lots of bacteria that are carried by dogs and cats. Exposing young children to these bacteria helps “exercise” their immune（免疫的） systems early in life so that they’re better able to resist allergic diseases later.

“There’s something very important in the first years of life when the immune system is developing that we can retrain it away from an allergic response,” said Dr. William Davis.

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56. Why do the researchers feel “very surprised” by the results of the study?

A. Because the results are contrary to what they have expected.

B. Because so many families are going to get rid of their cats and dogs.

C. Because parents are so much worried about their children.

D. Because children with animals may develop allergies easily.

57. Compared with children who have pets, those who haven’t ________.

A. will lose the chance to develop immune system

B. may suffer allergic diseases more often

C. will reduce the harm from bacteria

D. are more likely to resist allergic diseases

58. It can be inferred from the passage that ________.

A. pets are ill-treated by their owners

B. fewer families would like to own cats and dogs

C. keeping pets is a good way to keep children healthy

D. the results of the study can make families with pets feel at ease

59.The underlined word “it” in the fifth paragraph refers to ________.

A. the early life B. an allergic disease

C. immune system D. something important

60. What may be the best title of the passage?

A. How to protect your kids from allergies. B. Your pets may be helping your kids.

C. Bacteria do good to your kids. D. Advantages of owning pets.

Most children, even the youngest of children, are delighted to be around cats and dogs. But these pets carry plenty of germs and allergens（过敏原）,prompting researchers to ask: Are cats and dogs really safe for children？

A study finds that, contrary to many parents' fears, owning cats or dogs does not increase a child's risk of developing allergies, and in fact, may actually protect them. The study's lead author, Dr. Dennic Ownby of the Medical College of Georgia, says that even he was "very surprised" by the results. Ownby and colleagues followed more than 470 children from birth to age 6 or 7, comparing those exposed to cats and dogs during their first year of life to those who were not.

Even more remarkable, children who had two or more dogs or cats had an even greater reduction, up to 77 percent, in risk of allergies. Researchers suggest this protective effect may be the result of early exposure to lots of bacteria that are carried by dogs and cats. Exposing young children to these bacteria helps" exercise" their immune systems early in life so that they're better able to resist allergic diseases later.

There's something very important in that first year of life when the immune system is developing that we can retrain it away from an allergic response, said Dr. William Davis.

And while researchers are not encouraging parents to buy dogs or cats just to reduce a child's allergy risk, they say if a family already has one or more animals, there's no need to get rid of them.

1.Why do the researchers feel “very surprised” by the results of the study?

A．Because the results are contrary to their expectation．

B．Because so many children are playing with cats and dogs．

C．Because parents are so much worried about their children．

D．Because children with animals may develop allergies easily．

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A．will lose the chance to develop immune system

B．may suffer allergic diseases more often

C．will reduce the harm from bacteria

D．can keep doctors away

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A．pets are ill-treated by their owners

B．less families would like to own cats and dogs

C．keeping pets is a good way to keep children healthy

D．the results of the study can make families with pets feel at ease

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A．the early life

B．an allergic disease

C．immune system

D．something important

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A．How to protect your kids from allergies

B．Your pets may be helping your kids

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D．Advantages of owning pets

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