Scientists have uncovered the exact difference between man and mouse. Teams of scientists from around the world will publish today the draft(草图) genome(基因组) of the mouse, which enables them for the first time to compare another mammal’s entire DNA directly with that of a human.

The similarities are far greater than the difference－man and mouse share a comman ancestor that lived more than 70 million years ago－which has allowed scientists to find treatments for a good many human diseases.

British members of the project say the draft mouse genome, published in the journal Nature, has provided the “phrasebook” for scientists to translate the language of the human genome.

“The entire biomedical research community said for the first time fully using this resource to deal with human diseases. They will now have powerful tools that will serve them for many years to come,” said Dr. Jane Rogers, head of sequencing at the Welcome Trust Sanger Institute in Cambridge, which did 20 percent of the work.

Comparisons show almost every gene in the mouse has a corresponding(对应的) gene in humans－a 99 percent similarity that should help to find how each human gene works. Already the work has been able to show that man and mouse each have about 30,000 genes yet only 300 or so are unique to either species, increasing the value of the lab mouse as a “model” for human genetics.

This is an extraordinary milestone. For the first time we have an opportunity to see ourselves in an evolutionary(进化的) mirror. The mouse genome stands for a very important chapter in the lab notebook of evolution. By taking away genes to create sick mice, scientists have been able to reproduce a number disorders. Knowing the entire genomes of humans and mice will enable them to employ the technique more widely leading to a rapid development in the understanding of illnesses.

1．The importance of the discovery lies in the fact that __________.   

       A．man has finally found his true ancestor

       B．it will be easier for people to find the causes of human diseases and cure them

       C．it has enabled the scientists to compare human DNA with that of another mammal

       D．it makes it possible for man to understand the complicated language of his genome

2．The word “unique” in the fifth paragraph probably means ___________.

       A．having no like or equal                          B．the same

       C．corresponding                                     D．excellent

3．It can be inferred that _____________.

       A．almost every gene of a mouse works in the same way as that of a human being

       B．it has become easier for humans to find their real ancestor

       C．more mice will be used in scientific experiments

       D．scientists will use fewer mice in their experiments to protect them

4．Which of the following is the best title of the passage?

       A．Mouse “Book of Life” May Provide Cures for Human Diseases

       B．Mice and Men Are the Same

       C．Man and Mouse Share a Common Ancestor

       D．The Difference Between Man and Mouse

　　阅读理解：阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项．

　　Scientists have uncovered the exact difference between man and mouse.

　　Teams of scientists from around the world will publish today the draft (草图) genome (基因组) of the mouse, which enables them for the first time to compare another mammal's entire DNA directly with that of humans.

　　The similarities are far greater than the differences. Man and mouse share a common ancestor that lived more than 70 million years ago, which has allowed scientists to find treatments for a good many human diseases.

　　British members of the project say the draft mouse genome, published in the journal Nature, has provided the “phrasebook for scientists to translate the language of the human genome.”

　　“The entire biomedical research community can for the first time fully use this resource to deal with human diseases. They will now have powerful tools that will serve them for many years to come,” said Dr. Jane Rogers, head of sequencing at the Welcome Trust Sanger Institute in Cambridge, which did 20 percent of the work.

　　Comparisons show almost every gene in the mouse has a corresponding (对应的) gene in humans－a 99 percent similarity that should help to find how each human gene works. Already the work has been able to show that man and mouse each have about 30,000 genes yet only 300 or so are unique to either species, increasing the value of the lab mouse as a “model” for human genetics.

　　This is an extraordinary milestone. For the first time we have an opportunity to see ourselves in an evolutionary (进化的) mirror. The mouse genome stands for a very important chapter in the lab notebook of evolution. By taking away genes to create sick mice, scientists have been able to reproduce a number of human disorders. Knowing the entire genomes of humans and mice will enable them to employ the technique more widely, leading to a rapid development in the understanding of illnesses.

1．Scientists have found that________.

[　　]

A．men and mice are actually the same kind of animal

B．mice are actually the ancestors of human beings

C．the genome of mice is the same as that of humans

D．humans and mice most probably have developed from the same ancestor

2．The importance of the discovery lies in the fact that________.

[　　]

A．man has finally found his tree ancestor

B．it will be easier for people to find the causes of human diseases and cure them

C．it has enabled the scientists to compare human DNA with that of another mammal

D．it makes it possible for man to understand the complicated language of his genome

3．The underlined word “unique” in the sixth paragraph probably means________.

[　　]

4．It can be inferred that________.

[　　]

A．every gene of a mouse works in the same way as that of a human being

B．it has become easier for humans to find their real ancestor

C．more mice will be used in scientific experiments

D．scientists will use fewer mice in their experiments to protect them

5．Which of the following is the best title of the passage?

[　　]

A．Mouse's “Book of Life” May Provide Cures for Human Diseases

B．Mice and Men Are the Same

C．Man and Mouse Share a Common Ancestor

D．The Difference Between Man and Mouse