问题 读图填空题

某班同学用围棋子模拟生殖细胞来探究生男生女的比例问题。探究的方法是:甲袋中装入100粒白色围棋子,乙袋混合装入白色、黑色围棋子各50粒。每次从甲、乙两袋分别随机摸出1粒围棋子进行组合,1粒黑子1粒白子的组合用A表示,2粒白子的组合用B表示,每个小组组合20次。全班5个小组的实验结果如下表所示:

(1)黑色围棋子模拟的性染色体类型是______________,白色围棋子模拟的性染色体类型是____________。

(2)分别从甲袋和乙袋中各取1粒围棋子,如果组合为A,则表示所生“孩子”的性别为____________。

(3)为使实验结果更为可靠,应对各小组获得的实验数据如何处理?_____________。

(4)根据该实验结果得出的结论是_____________________。

答案

(1)Y;X

(2)男性

(3)相加(或取平均值)

(4)生男生女是随机的,机会是均等的(生男生女的比例是1:1)

阅读理解

阅读理解。

     There is a big supermarket near my home. Its name is Price-low.

     It has  lots  of things. You  can  buy  school things,  like  notebooks,  pens,  rulers,  erasers  and

pencil-sharpeners.  You can  buy vegetables,  fruit and all kinds of food.  You can also buy clothes.

Some of the things there are cheap(便宜的) , and anybody can afford the prices. But some of them

are dear.

     The supermarket is open  every  day from 9 :00 am t0 9 :30 pm.  The workers there are friendly.

They work hard all day. They are happy to answer your questions. They help you if you want to buy

some things. There are  many people  on  weekends.  They buy lots of things.  Sometimes they have

breakfast, lunch or dinner there, too.

1. The supermarket near my home is           .

A. new      

B. old      

C. smal    

D. big

2. kinds of school things are talked about.       

A Three    

B. Four    

C. Six    

D. Five

3.  The underlined(画线的) word "dear" here means"____" in Chinese.    

A.亲爱的    

B.宝贵的    

C.昂贵的  

D.精致的

4. The supermarket is open for about _______hours every day. 

A. seven    

B. six      

C. twelve  

D. ten

5. Which of the following is RIGHT?   

A. You can't buy clothes in the supermarket.

B. Some of the things in the supermarket are cheap, and some are dear.

C. The workers in the supermarket are not very good.

D. People can't have breakfast in the supermarket.

单项选择题