允许离子和小分子物质在细胞间通行的结构是（） A.化学性突触 B.紧密连接 C.缝隙

发布时间：2018-11-25 16:15 │ 来源：www.tikuol.com

题型：单项选择题

问题：

允许离子和小分子物质在细胞间通行的结构是（）

A.化学性突触

B.紧密连接

C.缝隙连接

D.桥粒

E.曲张体

考点：公卫执业医师细胞的基本功能细胞的基本功能题库

题型：单项选择题

阅读理解。

George Stephenson was born in 1781 in a poor family. He had to start work when he was only eight.
When George was fourteen, he became his father's helper. He spent a lot of time learning about engines
(发动机). And on holidays he often made one engine to pieces and studied each piece carefully. Soon he
became a very good worker though he could not read or write. He began to learn English letters when he
was seventeen years old. Every day after he did twelve hours of hard work,he walked a long way to have
lessons from a young school teacher. On his eighteenth birthday, he wrote his own name for the first time
in his life. George invented (发明) many things in his life. The train was the greatest one among them.
Today when we take trains from one place to another, we'll think of this great man-George Stephenson.

1. In which year did George Stephenson start to help his father? ______.

A. In 1781
B. In 1789
C. In 1795
D. In 1798

2. He learned about the engine ______.

A. through reading and writing
B. by making it to pieces and studying each piece carefully
C. at lessons from a young teacher
D. by asking a lot of questions

3. He spent a lot of time learning about engines and soon he became ______.

A. a great man
B. a good maker
C. a good worker
D. a good student

4. George Stephenson invented the ______.

A. the train
B. the telephone
C. the car
D. the computer

5. From the passage we know George Stephenson was one of the greatest ______ in the world.

A. workers
B. writers
C. learners
D. inventors

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题型：单项选择题

电冰箱工作时，应当使用图中的______插座，这是为了使电冰箱的外壳______，保证

安全工作．下表是某电冰箱的说明书，它正常工作时，电压是______V，若压缩机连续正常工作1h，将消耗电能______kwh．h．

额定电压	220V
频率	50Hz
额定功率	200W
容积	180L

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题型：单项选择题

时装的流行，年轻人发型和发色的变化等属于时尚类型的( )

A．阵热

B．狂热

C．时狂

D．时髦

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题型：单项选择题

会计师事务所及其注册会计师应当勤勉尽责，对出具报告所依据的文件资料内容的（）进行核查和验证。

A．真实性

B．准确性

C．合法性

D．完整性

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题型：单项选择题

作为一种管理方法，六西格玛管理包括的重要方面有（）。

A.六西格玛定型

B.六西格玛设计

C.六西格玛改进

D.六西格玛验证

E.六西格玛确定

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