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问题 选择题

结合表中数据，指出下列叙述正确的是

[ ]

A．细胞膜上糖类的含量多与细胞膜的选择透过性有关

B．细胞膜上的糖类与细胞膜的结构特点有关

C．细胞膜上的糖类的主要功能是参与识别和信息传递

D．生物膜之间的相互转化依赖于膜上的糖类物质

答案

C

填空题

用单词的正确形式填空

1. He happened            __  __(help) an old woman on his way home.

2. I have forgotten____(return) his money, so he didn't receive.

3. I spent about half an hour in____(write) yesterday's diary.

4. She was very busy, so I let her____(go) back first.

5. At least we can afford         ____(buy) an electric bike.

6. I had something to ask him, but he avoided___    ( answer) my question.
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单项选择题

有关肺心病肺动脉高压形成机制的描述，错误的是

A．慢性缺氧所致肺血管重建是肺动脉高压形成的重要因素

B．体液因素变化在缺氧性肺血管收缩中起重要作用

C．低氧和高碳酸血症纠正后，肺动脉压可明显降低

D．高碳酸血症使肺血管对缺氧收缩敏感性增强

E．缺氧不能直接使肺血管平滑肌收缩
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