3.(10新课标)下列有关细胞的叙述，正确的是

A．病毒是一类具有细胞结构的生物

B．蓝藻细胞具有细胞核且DNA分子呈环状

C．人体所有细胞的细胞周期持续时间相同

D．内质网膜和高尔基体膜都具有流动性

[答案]D

[解析]病毒不具有细胞结构，是没有细胞结构的生物。蓝藻为原核生物，没有核膜包围的真正细胞核。细胞周期持续的时间，不同细胞的细胞周期不同。细胞膜、内质网膜等膜结构都具有一定的流动性，这是生物膜结构的结构特点。

[评析]本题考察了生物必修I中关于细胞的内容，讨论了有细胞结构的生物和无细胞结构的生物，真核细胞和原核细胞的区别，生物膜的流动镶嵌模型的构建，以及细胞周期的内容，应该说考察的难度不高，非常适合作为高考的第一题。不过个难度的试题处在高考中还是有点让人意外的。

4.(10山东理综)溶酶体具有细胞内消化功能，其内部水解酶的最适PH在5.0左右，下列叙述错误的是

A、溶酶体内的水解酶是由核糖体合成的

B、溶酶体执行功能时伴随其膜组分的更新

C、细胞质基质中的被转运到溶酶体内需消耗能量

D、正常生理状态下溶酶体对自身机体的细胞结构无分解作用

[答案]D

[解题立意]本题考查溶酶体与酶、运输等的关系，考查综合分析能力。

[解题思路]水解酶属于蛋白质，是在核糖体上合成的，溶酶体属于生物膜系统，在消化细胞内的物质时要吞噬这些物质，形成具有消化作用的小泡，所以溶酶体执行功能时要发生膜成分的更新，的运转方式是主动运输，需要消耗能量，正常状态下机体也要产生衰老、凋亡细胞，死亡后溶酶体要对他们进行分解消化。

2.(10重庆卷)下列有关细胞结构和功能的叙述，正确的是

A.　　 在植物细胞有丝分裂末期高尔基体参与细胞壁形成

B.　　 在动物细胞有丝分裂间期能观察到纺锤体和中心体

C.　　 分泌蛋白合成后在内质网和细胞质基质中加工

D.　　 质粒和线粒体是既有核酸又有外膜的细胞结构

答案：A

解析：在植物细胞有丝分裂末期细胞壁形成，而细胞壁形成与高尔基体有关，故答案A正确。在动物细胞有丝分裂前期能观察到纺锤体和中心体，所以答案B错。分泌蛋白合成后在内质网和高尔基体中加工，故答案C错。质粒是只是环状的DNA，线粒体是双层膜的结构里面有DNA，故答案D错。

分析：此题考查了细胞的结构和有丝分裂过程相关知识，以及生物膜系统的相关知识(选修)，此题属识记类，为容易题。

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1.(10全国2)下列关于高尔基体的叙述，错误的是

A．　 高尔基体膜具有流动性

B．　 抗体从合成到分泌不经过高尔基体

C．　 高尔基体膜主要由磷脂和蛋白质构成

D． 高尔基体具有对蛋白质进行加工的功能

选B

解析：抗体的本质是蛋白质，其合成所需的细胞器有：核糖体、内质网、高尔基体和线粒体

80.What does the writer try to tell us?

A.　　　 Water Authorities Association gives a call to East Britain.　

B. Some water companies are in difficulty.

C. East Britain faces early water restrictions.　

79.From the spokesman, we can infer that _________.

　　　 A. generally Britain has much rainfall all the year round

　　　 B. usually after March or April it begins to rain in Britain

　　　 C. in the worst hit areas underground water remains acute

　　　 D. some areas have failed to pump water from the west to the east

78.From the passage, we learn that before Britain reported its third lowest rainfall________.

A. there was likely to be no rain for a long time

B. there was likely to be an average rainfall

　　　 C. underground and surface water was adequate

　　　 D. surface water was short but underground water adequate

77.What happened in East Anglia?

A. Water restrictions.　　　　　　　　　 B. A severe shortage of water supply.

C. Recovery from a drought.　　　　　　 D. Overflow of underground water.

76.The most important thing for a company to keep its employees loyal and energetic is ____.

　　　 A. to raise their salary from time to time　

B. to maintain an effective management

　　　 C. to be skillful in organizing their work　

D. to pay attention to the development of products

　　　　　　　　　　　　　 No. 20

Underground water reserves in eastern England are critically low and for some people water

　restrictions may only be days away. Areas affected include East Sussex, Kent and Essex. East Anglia is among the worst hit areas, with the situation in Lincolnshire “particularly acute (严重)”.

Yorkshire Water is still trying to recover from a drought last year and water is being pumped from the west of the country to the east to cope with an acute shortage.

The concern over areas which depend heavily on underground water reserves is also reported in the New Civil Engineer. It suggests that ground water levels have sunk to a record low and river flows have fallen as Britain recorded its third lowest rainfall for March and April this century. The journal also claims that some areas could be facing the worst drought in memory.

The problems stem from the dry winter of 1988-89 which preceded (先于) a long summer of drought followed by barely average rainfall in the East of England last winter.

A spokesman for the Water Authorities Association said areas dependent on surface water had made up for two years of dry weather while areas dependent on underground water reserves had never totally recovered.

“I know that some of the water companies in these areas are already giving warnings to customers to use water sensibly as they are already in some difficulty.”

75. If a company wants to hire excellent employees, it should __________.

　　　 A. offer agreeable working conditions to its employees

　　　 B. examine its employees and make selection strictly

　　　 C. take great care of the welfare of their employees

　　　 D. catch up with other companies in providing other benefits than wages

74. Today’s employees know how to protect their benefits by _________.

　　　 A. making comparisons between different companies

　　　 B. examining their agreements with the employer

　　　 C. asking for compensation for what they do　

D. changing their jobs more often than before