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4.下列有关基因工程的叙述,正确的是                 (   )

   A.DNA连接酶只能将同一种限制性核酸内切酶切割而成的黏性末端连接起来

   B.目的基因导入受体细胞后,受体细胞即发生基因突变

   C.目的基因与质粒结合的过程发生在细胞外 

   D.常使用的运载体有大肠杆菌、噬菌体和动植物病毒等

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3.下列有关细胞生命活动的叙述,正确的是               (   )

   A.卵细胞体积较大有利于和周围环境进行物质交换,为胚胎早期发育提供所需养料

   B.植物根尖细胞中均能转录和翻译的场所有细胞核和线粒体

   C.凋亡细胞内的基因表达都下降,酶活性减弱

   D.蛋白质通常不是生物体内的能源物质

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2.下图为生态系统中能量流动的部分示意图,①②③④⑤各代表一定的能量值,下列各项中正确的是                               (   )

   A.在人工饲养的高密度鱼塘中⑤肯定大于①   

   B.④中包含了次级消费者粪便中的能量

   C.在食物链中各营养级获得能量的方式及能量的用途完全相同

   D.第二营养级流向第三营养级的能量传递效率为(②/①)×100%

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1.下列关于胚胎工程的相关叙述不正确的是                (   )

   A.哺乳动物核移植包括胚胎细胞核移植和体细胞核移植,动物体细胞核移植的成功率明显小于胚胎细胞核移植

   B.诱导胚胎干细胞分化成器官的培养基中不需要加入饲养层细胞

   C.胚胎干细胞是一类未分化细胞,具有二倍体核型,可从早期胚胎中分离获取

   D.胚胎分割时需将原肠胚的内细胞团均等分割

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第一节:改错: 请找出下列短文中的错误,并改正。

注意, 没有错误的不用改。(每小题0.5分共5分)

I was used to complain about my English teacher           1.___________

for his bad English. I was also tired with his teaching methods,      2.___________

it were always slow and boring. However, my attitude towards       3.___________

him began to change after one afternoon. It was raining          4.___________

heavy and I didn’t attend school. Around 5:30 pm I received        5.___________

a phone call. “Are you all right?” asked my English teacher in quiet     6.___________

voice. On hearing her words, I was shocked and my mind was       7.___________

flooded with mixed feeling. He was showing his concern         8.___________

for me, though I have not been happy with him! Was he just         9.___________

acting and should I smooth away my past misunderstanding of him?     10.___________

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