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问题 单项选择题

在一些山区的溪流里能见到一些大蝌蚪没能正常完成变态发育，其原因是体内缺乏（）

A.性激素

B.生长激素

C.生长抑制素

D.甲状腺激素

答案

参考答案：D

解析：

性激素是促进生殖细胞的产生，A错误，生长激素主要促进骨的生长和蛋白质的合成，B错误，生长抑制素与生长激素作用相反，C错误。甲状腺激素的作用包括促进生物的生长发育，本题选D。

考点：激素的作用

选择题

冬季，一个坐火车外出旅行的人，当他到达目的地时，原来一只空旅行袋已装满了他一路上不得不脱下的衣服．此人的旅行路线可能是（　　）

A．北京--哈尔滨

B．广州--昆明

C．哈尔滨--南宁

D．北京--乌鲁木齐
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单项选择题

What’s your earliest childhood memory Can you remember learning to walk Or talk The first time you heard thunder or watched a television program Adults seldom (1) events much earlier than the year or so before entering school, (2) children younger than three or four (3) retain any specific, personal experiences.

A variety of explanations have been (4) by psychologists for this "childhood amnesia". One argues that the hippo-campus, the region of the brain which is (5) for forming memories, does not mature until about the age of two. But the most popular theory (6) that, since adults don’t think like children, they cannot (7) childhood memories. Adults think in words, and their life memories are like stories or (8) one event follows (9) as in a novel or film. But when they search through their mental (10) for early childhood memories to add to this verbal life story, they don’t find any that fit the (11) It’s like trying to find a Chinese word in an English dictionary.

Now psychologist Annette Simms of the New York State University offers a new (12) for childhood amnesia. She argues that there simply aren’t any early childhood memories to (13) . According to Dr. Simms, children need to learn to use someone else’s spoken description of their personal (14) in order to turn their own short-term, quickly forgotten (15) of them into long term memories. In other (16) , children have to talk about their experiences and hear others talk about (17) — Mother talking about the afternoon (18) looking for seashells at the beach or Dad asking them about their day at Ocean Park. Without this (19) reinforcement, says Dr. Simms, children cannot form (20) memories of their personal experiences.

2（）

A. now that

B. even if

C. as though

D. just as
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