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问题 单项选择题 A1/A2型题

关于生长激素的表述不正确的是 （）

A.成人体内含量升高可致肢端肥大症

B.分泌不足可致婴幼儿侏儒症

C.呈脉冲式分泌，清晨分泌达高峰

D.可刺激肝脏生成IGF-1

E.本质为蛋白质、肽类

答案

参考答案：C

解析：生长激素是垂体前叶分泌的多肽类激素，主要生理功能为促进生长，分泌有昼夜节律变化，夜间熟睡后约1小时起有数次较大的脉冲分泌，脉冲式分泌期外基本无释放。因此本题正确答案是C。

单项选择题

C

On Christmas Eve—the night before Christmas Day—children all over Britain put a stocking at the end of their beds before they go to sleep. Their parents usually tell them that Father Christmas will come during the night.

Father Christmas is very kind-hearted. He gets to the top of each house and climbs down the chimney into the fireplace. He fills each of the stockings with Christmas presents.

Of course, Father Christmas isn’t real. In Jim and Kate’s house, "Father Christmas" is really Mr. Green. Mr. Green doesn’t climb down the chimney. He waits until the children are asleep. Then he quietly goes into their bedrooms and fills their stockings with small presents. When they were very young, Mr. Green sometimes wore a red coat. But he doesn’t do that now. The children are no longer young, and they know who "Father Christmas" really is. But they still put their stockings at the end of their beds.

Father Christmas comes into the house through the （）.

A．chimney

B．back door

C．front door

D．window
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单项选择题

在精馏过程中，精馏原料是经（）后进入精馏塔的进料段。

A、加热、减压

B、加热、加压

C、冷却、加压

D、冷却、减压
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