试题与答案

某生物学习小组开展“环境水质对青蛙受精卵孵化的影响”的探究活动:制作2组生态瓶并

题型:解答题

题目:

某生物学习小组开展“环境水质对青蛙受精卵孵化的影响”的探究活动:制作2组生态瓶并编号,A组各加入200ml的清水,B组加入200ml一定浓度的污水;然后各放入100粒青蛙卵到瓶中,在相同适宜的环境中孵化.请分析作答.

(1)实验时需要定时观察记录的主要内容是______.

(2)他们选取受精卵数量为100粒而不是5粒的是______.

(3)若其中有一组孵化出小蝌蚪的数量少且部分形态异常,你估计是______组,原因是______.

答案:

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参考答案:A解析:[考核要点] 本题考核的是第一章第二节总供给与总需求。[解题思路] 总需求是指在一定时期内和一定价格水平上,全社会对产品和服务的总购买力或总支付能力。它必须通过市场交换才能实现,因此,...

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题型:阅读理解

阅读理解。

     Dick lived in England. One day in January he said to his wife, "I'm going to fly to New York next

week because I've got some work there." "Where are you going to stay there?" his wife asked. "I don't

know yet." Dick answered. "Please send me your address from there in a telegram (电报)," his wife

said. "All

right," Dick answered.

     He flew to New York on January 3<http://gk.>st and found a nice hotel in the center

of the city. He put his things in his room and then he sent his wife a telegram. He put the address of his

hotel in it.

     In the evening he didn't have any work, so he went to a cinema. He came out at nine o'clock and

said, "Now I'm going back to my hotel and have a nice dinner."

     He found a taxi (出租车) and the driver said, "Where do you want to go?" But Dick didn't

remember the name and address of his hotel.

     "Which hotel are my things in?" he said, "And what am I going to do tonight?" But the driver of

the taxi did not know. So Dick got out and went into a post office. There he sent his wife another

telegram, and in it he wrote, "Please send me my address at this post office."

Choose the right answer

1. Dick flew to New York because ___.

A. he went there for a holiday

B. he had work there

C. he went there for sightseeing (观光)

D. his home was there

2. Why did his wife want a telegram from him?

A. Because she didn't know his address yet

B. Because she wanted to go to New York, too

C. Because she might send him another telegram

D. Because she couldn't leave her husband by himself in New York

3. Where did Dick stay in New York?

A. In the center of the city.

B. In a hotel.  

C. In a restaurant.

D. At his friend's house.

4. Who would send him the name and address of his hotel?

A. The manager of his hotel.

B. The police office.  

C. The taxi driver.

D. His wife

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