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问题 填空题

冷冻作为一种很好的保藏食品的方法，其益处来自于（）。事实上，在具细胞结构的食品和食品凝胶中冰的形成会产生一些有害结果：（1）（）（2）（）。

答案

参考答案：低温而不是冰的形成；在非冷冻相中非水组分被浓缩；水转变成冰时体积增加9%

阅读理解
阅读短文，根据短文内容，从短文后的五个选项中选出能填入空白处的最佳选项.选项中有一项为多余选项。

   If you ask a teacher in China what makes a good student, he or she would probably tell you that a
good student is someone who gets high marks in exams. It is true that most teachers share this opinion.
1_____She says that as an educator,she feels sorry about what her students have to do every day. She
hates to see her students study day and night for the endless exams.These teenagers have no time to
relax or hang around with their friends. rrhey shouldn't be turned into book-worms(书呆子).2______  
Shen Hong thinks a good student should be like this:    
    A good student is honest and kind to others. 3______If he does something wrong, he says sorry
immediately. A-part from this,a good student is always ready to help hisfriends when they are in trouble.      
    A good student is one who always tries his best instudies. He makes full use of his time to learn both
in andout of class. Hard work comes first no matter how cleverhe is. 4 ______   He often plays ball
games or goes campingwith his friends. In a word, he develops in an all-round way.

A. In other words, he never lies to his friends.
B. However, one teacher called Shen Hong has a different attitude.
C. And it's also not right to judge a student only by the marks.
D. But a goog student should work hard all the time.
E. Besides studying,he also likes outdoors sports.

查看答案
单项选择题 A型题

主动转运是（）

A．从浓度高的一侧向浓度低的一侧扩散

B．耗能，且不受饱和限速与竞争抑制的影响

C．逆浓度梯度转运

D．受脂溶性和极性等因素影响

E．利用膜内载体促进代谢物扩散且不耗能
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