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问题 选择题

实验室内有一群基因突变的老鼠，这些老鼠只要按时喂食并且不让它们运动，它们就能维持正常。当它们进食后，它们的血糖浓度会轻微上升，然后下降至一个恒定状态；然而只要让老鼠运动或禁食一餐，它们的血糖浓度就会迅速下降，进而昏迷。这些突变老鼠出现上述状况的原因最可能是[ ]

A．胰岛B细胞受损

B．甲状腺被切除

C．无法将血糖转换成肝糖原

D．体内细胞缺乏胰高血糖素的受体

答案

答案：D

单项选择题

有下列程序段：
typedef struct NODE
int num；struct NODE*next；
OLD；
下列叙述中正确的是( )。

A) 以上的说明形式非法
B) NODE是一个结构体类型
C) OLD是一个结构体类型
D) OLD是一个结构体变量
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单项选择题

Can you believe it There’s a world paper shortage. There’s a national bottle shortage, and we’re running out of raw materials like timber and tin -- or so the papers say. Well, I’ve just emptied my shopping basket after my weekly shopping trip and it was full of things made from these scarce materials. Half of what I’d bought I threw away at once; all those unnecessary paper bags, plastic bags, fresh wrapping paper and old newspapers they put the food in nowadays.
Modern packaging makes shopping cleaner and more convenient, but at what cost Every time you throw away a paper bag you’re throwing away part of a tree -- and trees don’t grow overnight! At this rate there soon won’t be any trees left, and then what shall we do
Perhaps we’ll learn to do what my mother did. She used to keep a store of paper bags in a kitchen drawer and use them again and again for her shopping. Most goods were sold loose in those days. And the shopkeeper weighed out the amount you wanted. Of course, liquid goods have always been sold in bottles or cans, but why can’t we use these containers more than once If we re-use all our bottles we would save on the raw materials and energy needed to make new ones. At the moment 90% of our rubbish is just dumped. It’s time we started to think seriously about the growing shortage of raw materials in the world today.

What does the author want us to do
[A] He asks for an awareness of the shortage of raw materials.
[B] He wants us to use paper bags again and again.
[C] He wants us to buy liquid goods.
[D] He wants us to re-use all our bottles.
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