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问题 选择题

运用现代生物技术，将苏云金芽孢杆菌的抗虫基因整合到棉花细胞中，为检泐实验是否成功，最方便的方法是检测棉花植株是否有[ ]

A．抗虫基因

B．抗虫基因产物

C．新的细胞核

D．相应性状

答案

答案：D

填空题

阅读短文，用所给单词的适当形式填空。

     A telephone bell suddenly woke Mrs Whiteup.  She turned on the lighht and     1    (go) toanswer

it.  “Your mother _  2   _ (be) ill sincelast night,.” said her father.   I     3     (take)her to hospital. Can

you come back and help me?"Mrs White agreed.    

     She knew she couldn't come back by suppertime. The weather was hot, and she was afraid themilk

would get bad. She brought out a piece ofpaper and wrote, "No person     4    .(be) intoday.  Please

don't leave anything here. "  

     When she retumed home at night, she     5    (find) the rooms were empty. She sawa note on the floor. It said, "Thanks a lot. Wedidn't leave anything here. "

1.              2.             3.             4.              5.               

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单项选择题

视网膜色素变性可出现的视野改变为（）

A.向心性视野缩小

B.生理盲点扩大

C.弓形暗点

D.环形暗点

E.中心暗点
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