问题 单项选择题

下列有关生物膜结构和功能的描述,不正确的是()

A.细胞的融合依赖于细胞膜的流动性

B.合成固醇类激素的分泌细胞的内质网一般不发达

C.分泌蛋白的修饰加工由内质网和高尔基体共同完成

D.生物膜之间可通过具膜小泡的转移实现膜成分的更新

答案

参考答案:B

解析:细胞膜的组成成分有磷脂、蛋白质和糖类,其中细胞膜的基本骨架是磷脂双分子层,蛋白质或镶在磷脂双分子层表面,或嵌插于磷脂双分子层中,或贯穿于磷脂双分子层中;糖类与蛋白质结合形成糖蛋白,位于细胞膜的外表面。细胞膜的功能特性是选择透过性,结构特点是有一定的流动性。细胞的融合的原理是其结构特点,即细胞膜具有一定的流动性;分泌蛋白的合成是在核糖体上进行的,通过内质网的初加工和运输,以具膜小泡的形式运输到高尔基体再加工,从而具有生物活性;所以A、C、D正确。内质网是由膜连接而成的网状结构,是细胞内脂质合成的车间,所以合成固醇类激素的分泌细胞的内质网一般较为发达,故B不正确。考点:细胞膜的结构与功能点评:本题难度一般,主要考查细胞膜结构与功能的相关知识,要求学生了解细胞膜的组成、结构和功能。

阅读理解

Once upon a time, there lived a rich man. He had a servant (仆人). He and the servant loved wine and good food very much. Each time the rich man left his home, the servant would drink the wine and eat up all the nice food in the house. The rich man knew what his servant did, but he had never caught his servant doing that.

One morning, when he left home, he said to the servant, “Here are two bottles of poison (毒药) and some nice food in the house. You must take good care of them.” With these words, he went out.

But the servant knew that the rich man had said was untrue. After the rich man was away from his home, he enjoyed a nice meal. Because he drank too much, he was drunk and fell to the ground. When the rich man came back, he couldn’t find his food and his wine. He became very angry. He woke the servant up. But the servant told his story very well. He said a cat had eaten up everything. He was afraid to be punished(惩罚), so he drank the poison to kill himself.

小题1:In the story, _______ liked wine and good food very much.

A.the rich man

B.the servant

C.both A and B

D.neither A and B小题2:The rich man knew that it was _______ that drank the wine and ate up all the nice food.

A.the cat

B.himself

C.nobody

D.the servant小题3:The rich told the servant that there was poison in the two bottles, because ________.

A.there was in fact poison in the bottles

B.he did not want the servant to drink his wine

C.he wanted to kill the cat

D.he wanted to kill the servant小题4:In fact, _______ ate all the nice food and drank the wine.

A.the servant   

B.cat   

C.the rich man  

D.nobody小题5:From the story, we know that the servant is very _______.

A.lazy   

B.bad

C.clever   

D.kind

补全对话,情景问答