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问题 选择题

（2011滨州）近年来，克隆技术已被广泛用于许多相关领域，这必将导致生命科学的一场革命。克隆的含义是

A．组织培养

B．营养繁殖

C．无性生殖

D．有性生殖

答案

答案：C

克隆指的是，直接由一个动物细胞，利用现代生物技术产生出与亲代一模一样的后代，没有经过两性生殖细胞的结合过程，是无性生殖。

阅读理解

任务型阅读： 阅读下列短文，按要求完成下列各题。

    My name is Jack. I am twelve years old. I have many friends. Lots of them are my age. My best friend

is Ben. He is one year older than me. He lives near me. We go to the same (相同的) school. Ben and I are in

Class One. The others are in Class Two. Ben helps me with my maths homework because he is clever

at it. I help him with his English because I am good at it.

    Ben is 1.65 metres tall and I am 1.60 metres tall. Ben is fat because he doesn't like sports. We have black

hair and brown eyes, but Ben's hair is longer than mine. Every day, I, and, like sports, exercise. Every

evening we play computer games. Ben usually wins.

1. How old are lots of Jack's friends? (回答问题)

                                                                                                                         

2. Which class is Jack in? (回答问题)

                                                                                                                         

3. 根据短文内容填词：Jack and Ben often help                     with their lessons.

                                                                                                                         

4. 将第一处画线部分译成汉语：

                                                                                                                         

5. 将第二处画线部分组成正确的句子： 

                                                                                                                         
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选择题

在x轴上有两个点电荷，一个带正电荷Q1，另一个带负电荷Q2，且Q1＝4Q2 。用E1、E2分别表示这两个点电荷在x轴上的M点产生的场强的大小，用φ1、φ2分别表示这两个点电荷在x轴上N点产生的电势大小。以下说法正确的是（   ）

A．E1=E2的M点有两处，φ1=φ2的N点有一处

B．E1=E2的M点有一处，φ1=φ2的N点有两处

C．x轴上场强为零的点有两处、电势为零的点有一处

D．x轴上场强为零的点有一处、电势为零的点有两处
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