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6.下列说法正确的是(   )

A.“绿色荧光蛋白质”是不可降解的高分子化合物,其水溶液有丁达尔效应

B.“低碳”生活倡导节能,减少CO2的排放,禁止使用化石燃料

C.废弃的塑料、金属、纸制品及玻璃都是可回收再利用的资源

D.制作航天服的聚酯纤维和用于光缆通信的光导纤维都是新型无机非金属材料

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5.近年来,在疫苗家族中增加了第三代疫苗-DNA疫苗,它们是由病原微生物中的一段表达抗原的基因制成的,这段基因编码的产物仅仅引起机体的免疫反应。以下关于DNA疫苗的叙述正确的是

A.能引起特异性免疫反应是因为DNA疫苗具有抗原决定簇

  B.DNA疫苗引起免疫反应前必须经过转录和翻译的过程

   C.DNA疫苗导人人体后浆细胞分化为记忆细胞

   D.接种后若感染此病原微生物,则体内记忆细胞会迅速产生大量抗体

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4.我国科学工作者首次发现水稻根的负向光性:水稻的根在黑暗中是垂直生长的,若对黑暗中生长的根的一侧给以光照,约在1.5h后可看到根尖背光斜向生长以下是对黑暗中垂直生长的水稻根局部遮光和切除处理的结果:

处理
根尖的生长情况
1.对根冠以外部位遮光,对根冠单侧照光
负向光倾斜生长
2.对根冠以外部位单侧照光,对根冠遮光
继续垂直生长
3.完全剥除根冠,对根部单侧照光
能伸长生长,但失去负向光性
4.切除根冠和分生区,对根部单侧照光
有限的伸长生长,但失去负向光性
5.切除根冠、分生区和伸长区,对根部单侧照光
根停止生长,失去负向光性

以上结果表明,水稻的根感受光刺激和发生倾斜生长的部位分别是(   )

A.伸长区和根冠 B.根冠和分生区 C.根冠和伸长区   D.伸长区和分生区

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3.右图是某哺乳动物的某一器官切片中细胞分裂不同时期示意图,据图分析可推知(   )

A.该哺乳动物可能为雌性

B.甲图细胞中的染色体数和DNA分子数均为正常体细胞的二倍

C.乙图细胞中在分裂过程中较可能发生染色体交叉互换

D.甲乙两图的细胞中都存在同源染色体

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2.美国弗吉尼亚大学研究人员在有关癌症研究的杂志上发表论文称,他们发现了一种名为RHOGDl2的基因,该基因有助于避免癌细胞扩散,他们发现携带该基因的癌细胞会失去转移能力。该基因的作用最可能的是(   )

A.当这种基因添加到癌细胞后,在癌细胞中表达并产生一种糖蛋白

B.当这种基因添加到癌细胞后,在癌细胞中表达并产生一种蛋白质,由此使癌细胞迅速分化为其他组织、器官

C.该基因在癌细胞内表达后使癌细胞迅速衰老

D.该基因在癌细胞内表达后使癌细胞的DNA复制受阻,停止细胞分裂

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1.下列有关水在生物实验中作用的叙述,正确的是(   )

A.制备细胞膜时,用蒸馏水的目的是使哺乳动物红细胞吸水涨破,流出内容物,获得细胞膜

B.用清水漂洗已解离的洋葱根尖,是为了维持细胞活性

C.将洋葱鳞片叶浸润在水中,就可以发生质壁分离及复原现象

D.在提取绿叶中的色素时,用清水可以溶解色素

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VI. 完形填空:先通读下面短文,掌握其大意,然后从各小题所给的A、B、C、D四个选项中,选出一个最佳答案。共15小题,计15分。

Some students cheat(作弊) because they’re busy or lazy and they want to get good grades without (41) the time studying. Other students might feel that they can’t (42) the test without cheating. Even when there seems to be a “good reason” for cheating, it isn’t a good (43).

A student who thinks cheating is the only way to pass a test (44) to talk with the teacher and his or her parents so they can find some better ways together. Talking about these problems and (45) them out will help feel better than cheating.

   If a student gets (46) cheating, the teacher may give a “(47)” on the test, send him or her to the head teacher’s (48), and call his or her parents. Worse than the (49) grade may be the feeling of having disappointed those people, (50) parents and teachers. A parent may worry that you are not an (51) person and a teacher might watch you more (52) the next time you’re taking a test.

There are plenty of reasons why a kid shouldn’t cheat, but some students have already cheated. If that’s you, it’s (53) too late to stop cheating. Cheating can become a (54), but a student is always able to act better and make better (55). It might help to talk the problem over with a parent, teacher, or friend. 

41. A. taking         B. spending          C. costing           D. using

42. A. write          B. exercise           C. pass             D. expect 

43. A. idea           B. purpose           C. custom           D. conclusion

44. A. decides        B. hopes            C. refuses               D. needs

45. A. breaking       B. dreaming           C. missing           D. working

46. A. caught         B. offered           C. appeared          D. suggested

47. A. prize          B. result            C. zero             D. treat

48. A. office         B. school            C. seat              D. conversation

49. A. natural         B. dangerous         C. anxious           D. bad

50. A. and           B. besides           C. like              D. among

51. A. outside        B. advantageous       C. interesting         D. honest

52. A. closely         B. bravely           C. certainly          D. hardly

53. A. always         B. never            C. once             D. neither

54. A. menu          B. medicine          C. habit             D. match

55. A. education       B. decisions          C. challenges         D. risks     

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40. ---Does anyone know __________?                          

---I hear that he was born in Sweden.

A. what he is                B. when he was born

C. where he comes from                     D. which country is he from

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39. --- A new 3D movie is on. Shall we go and see it this weekend? 

---__________! What’s it?

A. I must be going now  B. You are right       C. Why not       D. My pleasure

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