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问题 单项选择题

艾弗里和其同事进行的“肺炎双球菌体外转化实验”证明了哪种物质才是转化因子？（）

A.R型的DNA

B.S型的DNA

C.S型的蛋白质

D.S型的多糖荚膜

答案

参考答案：B

解析：他们的实验证明了S型菌的DNA是转化因子，故选B。因为他们是将S型菌的蛋白质，多糖荚膜和DNA分别提取出来加入到有R型菌的培养基中，结果只有在S型菌的DNA上长成了S型菌。

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阅读下面短文，按要求回答问题。
    Fifteen is such an awful (糟糕的) age, I should know. I really wish I were eighteen. If you are an
adult, you can be your own boss. People like my parents and my teachers are always telling me what
to do. You know what I mean. "It's time for bed, Sandy." Or "Sandy, you've watched too much TV
for one night." "Sandy, stand up straight." "Sandy, you must improve your handwriting." Sandy this,
Sandy that. No one tells adults when they go to bed or not to watch TV. Besides, adults get to wear
what they like. Now it's going to be great to be an adult. Don't you agree?

     I'm Sandy's mother. Having a fifteen-year-old daughter isn't always easy. Right now, we've got
a problem. Our neighhour, Mrs White, wants Sandy to look after her pet dog for one week. Sandy
really wants to do it, but (I                          ). She's too young and inexperienced. Well, I will
never be able to relax knowing she is all alone with a dog. I've tried to explain my feelings to her,
but she won't listen. She keeps telling me that the Whites live very near, so she can ask for help.
She insists that Mrs White won't ask her to look after her pet dog if she doesn't think Sandy is old
enough. She says I'm "babying" her and I hate to see her mad at me. What should I do?
1. Sandy is fifteen years old and she wishes to be her own _______.
2. Sandy thinks her parents and her teachers are always telling her what to do. Give an example.
                                                                                                                                        
3. 将文中括号内的英文句子补充完整。
4. 将划线句子She says I'm "babying" her and I hate to see her mad at me. 译成汉语。 
                                                                                                                                         
5. Should Sandy look after Mrs White's pet dog? Why or why not? 
                                                                                                                                         
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多项选择题

下列哪些是内伤头痛的病因（）

A.饮食不节

B.房劳过度

C.禀赋不足

D.病后体虚

E.跌仆损伤
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