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问题 填空题

仔细观察，你会发现鱼的口和鳃盖后缘始终是一张一合，交替进行，这实际上是鱼在进行______，所以经鳃流出的水流与由口流入的水流相比，______含量减少，______含量增加．

答案

鱼类终生生活在水中，观察活鱼，可以看到鱼的口和鳃盖后缘有交替闭合的现象，这是鱼在呼吸．鱼用鳃呼吸，鳃上有许多鳃丝，鳃丝里密布毛细血管，当水由口流进，经过鳃丝时，溶解在水里的氧就渗入鳃丝中的毛细血管里，而血里的二氧化碳浸出毛细血管，排到水中，随水从鳃盖后缘的鳃孔排出体外，所以鱼类不停地吞水实际是在呼吸．

故答案为：呼吸；氧气；二氧化碳

单项选择题

In a country that defines itself" by ideals, not by shared blood, who should be allowed to work and live here In the wake of the Sept. 11 attacks these questions have never seemed more pressing.

On Dec. 11, 2001, as part of the effort to increase homeland security, federal and local authorities in 14 states staged " Operation Safe Travel"—raids on airports to arrest employees with false identification. In Salt Lake City there were 69 arrests. But those captured were anything but terrorists, most of them illegal immigrants from Central or South American. Authorities said the undocumented worker’s illegal status made them open to blank mall by terrorists. Many immigrants in Salt Lake City were angered by the arrests and said they felt as if they were being treated like disposable goods. Mayor Anderson said those feelings were justified to a certain extent. "We’re saying we want you to work in these places. We’re going to look the other way in terms of what our laws are, and then when it’s convenient for us, or when we can try to make a point in terms of national security, especially after Sept. 11, then you’re disposable. There are whole families being uprooted for all of the wrong reasons. " Anderson said.

If Sept. 11 had never happened, the airport workers would not have been arrested and could have gone on quietly living in America, probably indefinitely. Ana Castro, a manager at a Ben & Jerry’s ice cream shop at the airport, had been working 10 years with the same false Social Security card when she was arrested in the December airport raid. Now she and her family are living under the threat of deportation. Castro’s case is currently waiting to be settled. While she awaits the outcome, the government has granted her permission to work here and she has returned to her job at Ben & Jerry’s.

How did the immigrants in Salt Lake City feel about "Operation Safe Travel"（）

A．Guilty.

B．’Offended.

C．Disappointed.

D．Discourage
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选择题

能够反映物质分子做无规则运动快慢的物理量是（　　）

A．比热容

B．热量

C．温度

D．热量和温度
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