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科学家尝试使用Cre/loxP位点特异性重组系统,在检测目的基因导入成功后,删除转基因烟草细胞内的抗除草剂基因。其技术过程如下(图中的■代表基因前的启动子),据图回答下列问题:

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阅读下面材料,在空白处填入适当的内容(1个单词)或括号内单词的正确形式。

        In my living room, there is aplaque that advises me to “bloom ____youare planted”. It reminds me of Dorothy. I got to know Dorothy in the early1980s, when I was teaching Early Childhood Development through a program. Thejob ____(responsible) requiredoccasional visits to the classroom of each teacher in the program. Dorothystands out in my memory as on one ____bloomed in her remote area.

       Dorothy taught in a remote school nearHarlan. To get to her school from the town of Harlan, I followed a road ____(wind) around the mountain. In theeight-mile journey, I crossed the same railroad track five times, giving thepossibility of ____(catch) by thesame train five times. Rather than feeling excited by this drive throughmountains, I found it depressing. The poverty level was shocking and the smallshabby houses gave me the greatest feeling of ____(hope).

        From the moment of my arrival at thelittle school, all my gloom disappeared. Upon arriving at Dorothy's classroom,I was greeted with smiling faces and treated like a queen. The children____(prepare) to show me their ____(late) projects. Dorothy told me witha smile that they were serving poke greens salad and cornbread they madethemselves for dinner.

        Lonely ____she was far away from the moderncivilization and convenience, she never ran out of reports of excitingactivities of her students. Her enthusiasm never cooleddown. She passed all the tests ____(excellent)and I found that Dorothy was really blooming where life had planted her.