Far from the land of Antarctica(南极洲), a huge shelf of ice meets the ocean. At the underside of the shelf there lives a small fish, the Antarctic cod. For forty years scientists have been curious about that fish. How does it live where most fish would freeze to death? It must have some secret. The Antarctic is not a comfortable place to work and research has been slow. Now it seems we have an answer.

Research was begun by cutting holes in the ice and catching the fish. Scientists studied the fish’s blood and measured its freezing point.

The fish were taken from seawater that had a temperature of -1. 88℃ and many tiny pieces of ice floating in it. The blood of the fish did not begin to freeze until its temperature was lowered to -2. 05℃. That small difference is enough for the fish to live at the freezing temperature of the ice-salt mixture.

The scientists’ next research job was clear: Find out what in the fish’s blood kept it from freezing. Their search led to some really strange thing made up of a protein(蛋白质) never before seen in the blood of a fish. When it was removed, the blood froze at seawater temperature. When it was put back, the blood again had its antifreeze quality and a lowered freezing point.

Study showed that it is an unusual kind of protein. It has many small sugar molecules(分子) held in special positions within each big protein molecule. Because of its sugar content. It is called a glycoprotein. So it has come to be called the antifreeze fish glycoprotein, or AFGP.

1. What is the text mainly about?

A. The terrible conditions in the Antarctic.  

B. A special fish living in freezing waters.

C. The ice shelf around Antarctica.           D. Protection of the Antarctic cod.

2. Why can the Antarctic cod live at the freezing temperature?

A. The seawater has a temperature of -1. 88℃.

B. It loves to live in the ice-salt mixture.

C. A special protein keeps it from freezing.

D. Its blood has a temperature lower than -2. 05℃.

3. What does the underlined word “it” in Paragraph 5 refer to?

A. A type of ice-salt mixture.   B. A newly found protein.

C. Fish blood.               D. Sugar molecule.

4. What does “glycol-” in the underlined word “glycoprotein” in the last paragraph mean?

A. sugar         B. ice         C. blood         D. molecule

 第二节 短文改错(共10小题;每小题1分,满分10分)

此题要求改正所给短文中的错误。对标有题号的每一行做出判断:如无错误,在该行右边横线上画一个勾(√);如有错误(每行只有一个错误),则按下列情况改正:

此行多一个词:把多余的词用斜线( \ )划掉,在该行右边横线上写出该词,并也用斜线划掉。此行缺一个词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词。此行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。

注意:原行没有错的不要改。

At the age of fourteen Bell sent to London to                                         86._________

live for a year with his grandfather, that took good care                            87._________

of him. A year late young Bell returned to Scotland.           88._________

After working for time with his father, he began teaching        89._________

speech at a school. His free time was devoted to study              90._________

sound.Before he studied the human voice and the                91._________

vibrations(振动)that goes to make up sound, he found that the                92._________

voice is not a simple thing. So he continued on with his           93._________

studies and his teaching until at the age of twenty-third            94._________

he moved with his family to Canada.                 95._________

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