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问题 选择题

对体液免疫和细胞免疫异同的表述，不正确的是  [ ]

A．体液免疫中，抗体和抗原发生特异性结合，发挥兔疫效应

B．细胞免疫中，效应T 细胞的攻击目标是被抗原入侵了的宿主细胞

C．有免疫效应的是效应淋巴细胞

D．效应淋巴细胞都来自骨髓造血干细胞，都在骨髓中分化、发育成熟

答案

答案：D

完形填空
完形填空。
       It's a   1   Sunday morning. Mr and Mrs Green are going to the People's Park with   2   daughter, Ann. At
8 o'clock they go to the park   3   bus. On the bus there are a lot of people, men, women and   4  . Some are
Americans. Some are   5  . Others are Japanese. They are going to   6  , too. 
       There are   7   Chinese on the bus. One is a woman. She's driving the bus. The other is a teacher in a middle
school. He   8   English very well. He's now talking about the park. The people are   9   him. They want to get
there quickly. They hope to   10   there today!
( ) 1. A. good    
( ) 2. A. his      
( ) 3. A. by      
( ) 4. A. boys    
( ) 5. A. American     		B. fine    
B. her             
B. in     
B. girls   
B. Chinese            		C. well   
C. their            
C. on    
C. babies  
C. Japanese         		D. bad         
D. theirs                
D. after     
D. children                      
D. Englishman
( ) 6. A. Tian'anmen Square         
            C. the People's Park 		B. the Summer Palace                        
D. the Great Wall      
( ) 7. A. one        
( ) 8. A. says              
( ) 9. A. listening to 		B. two    
B. speaks               
B. seeing  		C. three   
C. talks                 
C. hearing 		D. many         
D. reads                             
D. looking for
( ) 10. A. be friends    
              C. have a good time 		B. see a good film   
D. buy something                    
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选择题

两颗人造地球卫星A和B的轨道半径分别为RA和RB，则它们的运动速率vA和vB，角速度ωA和ωB，向心加速度aA和aB，运动周期TA和TB之间的关系为不正确的是（　　）

A．vA：vB=

RB
：
RA

B．ωA：ωB=RB

RB
：RA
RA

C．aA：aB=R2A：R2B

D．TA：TB=RA

RA：RB
RB
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