问题
选择题
用动、植物成体的体细胞进行离体培养，下列叙述正确的是[ ]
A．都须用液体培养基
B．都需用培养箱
C．都要在无菌条件下进行
D．都可体现细胞的全能性
答案
答案：C
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用动、植物成体的体细胞进行离体培养，下列叙述正确的是[ ]
A．都须用液体培养基
B．都需用培养箱
C．都要在无菌条件下进行
D．都可体现细胞的全能性
答案：C
阅读下面短文，掌握其大意，然后从36～55各题所给的四个选项（A、B、C和D）中，选出最佳选项。 My First Day I was still shy in the presence of a crowd.And my first day at the new made me a laughing stock of the classroom. I was sent to the blackboard to write my .I knew my name, and knew how to write it, but standing at the blackboard with the ____ of so many pupils on my back made me inside and I was unable to write a single letter. "Write your name," the teacher called to me. I the white chalk to the blackboard and, as I was about to write, my mind went blank; I could not remember my name, the first letter. Somebody laughed and I became "Just forget us and write your name," the teacher called and walked to my side, at me to give me confidence. "What’ s your name?" she asked. "Richard," I ____ . "Then write it." I turned to the blackboard and lifted my hand to write, but then I was again. I tried to ___ my senses but I could remember nothing.I realized how totally I was and I grew weak and leaned my hot forehead the cold blackboard. The room burst into a loud and my muscles froze. I sat and myself.Why did I always appear so dumb I was called upon to perform in a crowd? I knew how to write as well as any other pupil in the classroom, and there was no I could read better than any of them, and I could talk when I was sure of myself. Then why did strange make me freeze? I sat with my ears and neck __, hearing the pupils around me whisper, hating myself.
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