题目

Summer is the best time on the Island of the Blue Dolphins (海豚). The sun is warm then and the winds blow out of the west,   1   out of the south.     It was   2   these days that the ship might return and now I   3  most of my time on the rock,   4   out from the headland(水中凸起的陆地) into the east, towards the country   5   my people had gone, across the   6   that was never-ending.     Once   7   I watched, I saw a small object which I took to be the ship, but a stream of water   8   from it and I knew that it was whale (鲸鱼根据所学生物学知识回答:(1)如果要将某目的基因通过农杆菌转化法导入植物细胞,先要将目的基因插入农杆菌Ti质粒的 中,然后用该农杆菌感染植物细胞,通过DNA重组将目的基因插入植物细胞的 上.(2)目前临床上使用的红细胞生成素(一种糖蛋白,用于治疗肾衰性贫血)主要来自基因工程技术生产的重组人红细胞生成素(rhEPO).检测rhEPO的体外活性需用抗rhEPO的单克隆抗体.分泌该单克隆抗体的 细胞,可由rhEPO免疫过的小鼠 细胞与小鼠骨髓瘤细胞融合而成.(3)在“试管牛”的培育过程中,采用激素处理可使良种母牛一次排出多枚卵母细胞,最常用的激素是 .从良种公牛采集的精子需 后才能进行受精作用.在胚胎移植前,通过 技术可获得较多胚胎.(4)生态系统内即使某个物种由于某种原因而死亡,也会很快有其他物种占据它原来的生态位置,从而避免系统结构或功能失衡.这体现了生态工程的什么原理 A.协调与平衡原理         B.物种多样性原理    C.物质循环再生原理     D.整体性原理.
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