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问题 单项选择题

将紫色洋葱鳞片叶表皮置于质量浓度为0.3g/ml的蔗糖溶液中，原生质层和细胞壁之间将（）

A.紧紧贴在一起

B.充满细胞液

C.充满蔗糖溶液

D.充满清水

答案

参考答案：C

解析：因为洋葱细胞细泡液的浓度一般低于0.3g/ml的蔗糖溶液，细胞发生质壁分离，原生质层和细胞壁之间存在空隙，其中充满蔗糖溶液，故选C。

完形填空
完形填空。
    You'll see a new doctor at a hospital near London if you go there. He's very clever,   1   he never speaks.
He can work 24 hours a day and never gets   2  . He's one metre tall and has a face   3   a TV screen. He is
Dr Robot. 
     Doctors   4   need to ask their patients a lot of questions.   5   doctors can only spend a few   6   with
each patient. But Dr Robot can ask a paitent for an hour if it is   7  . With the help of Dr Robot, a human
doctor can   8   a lot of useful information when he meets his patient. 
       9   can Dr Robot do this? A computer tells him to do. Dr Robot can do a lot of things people can do,
though he can't completely  10  the place of huan doctors.
( )1. A. so        
(     )2. A. tired     
(     )3. A. like      
(     )4. A. don't    
(     )5. A. Kind      
(     )6. A. seconds   
( )7. A. late      
(     )8. A. lose      
(     )9. A. How       
(     )10. A. bring      		B. if        
B. off       
B. on          
B. must     
B. Busy      
B. minutes   
B. impossible    
B. have      
B. Why       
B. give       		C. but          
C. up           
C. as            
C. never      
C. Free          
C. hours         
C. necessary     
C. send         
C. Where        
C. take        		D. because        
D. angry          
D. in                
D. often           
D. Poor             
D. days              
D. interesting                     
D. spread           
D. When              
D. show         
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单项选择题 A1/A2型题

高密度脂蛋白胆固醇测定的参考方法是（）

A.肝素-Mn2+沉淀法

B.磷钨酸钠-Mg2+沉淀法

C.超速离心法

D.聚乙二醇沉淀法

E.电泳分离法
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