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问题 读图填空题

如图是某生物的精原细胞分裂过程图，试据图回答相关问题：

(1)精原细胞除能发生图示的分裂方式外，还可进行_________分裂实现增殖。

(2)从染色体组成看，图中细胞a和细胞b中染色体组成的特点是________________。

(3)图中分裂产生的细胞A与细胞a中染色体数目、DNA数目比例分别为_______、_______。精原细胞分裂形成细胞A、B时，分裂期的主要变化特点是_____________________，这是孟德尔两个遗传规律的细胞学基础。

(4)试在下面的坐标图中表示该精原细胞分裂过程中“细胞内DNA数目与染色体(质)数目比例”的变化情况。

答案

(1)有丝

(2)相同

(3)1：1 2：1 同源染色体上的等位基因相互分离、非同源染色体上的非等位基因自由组合

(4)

问答题
综合性学习。
　　某社区（村委会）将举办一次主题是“生态与文明”的图片展览，下面是这次展览的部分素材。假设你是这次展览筹备工作的参与者，请发挥自己的聪明才智来完成以下几项任务。                                                 
A组标题：____ 

A1．爽爽的贵阳，避暑的天堂。

A2．故乡真是天蓝蓝，水清清，空气也清新。

A3．生态文明与民族风情交融

A4．______________
B组标题：____

B1．南明河上漂浮的不是垃圾 ，而是某些人的粗俗。

B2．______________ 

B3．赤膊穿行于闹市，仪不雅，态不美 。
 
B4．她跨过了隔栏杆，却丢失了文明心。
⑴请将下面提供的语言材料重新组织润色，使之成为一段思路连贯、中心明确、语言畅达的文字，作为展览中的“写在前面的话”，来介绍举办展览的目的意义。（可以调整顺序和添加适当文字。）    
①人与自然和谐相处
②为所欲为  肆无忌惮 
③优美舒适的人居环境
④树立生态文明观念   提高市民的文明素质
__________________________________________
⑵图片共分A、B两组，请任选一组拟出恰当的标题。
__________________________________________
⑶请为A4（车上让座）、B2（人为山火）两幅图片分别配上精练的说明文字。
__________________________________________    
⑷展览室中将挂上一副对联，别人已写了上联，请你写出下联。（内容须与展览主题吻合。）     
上联：提高文明素养创建美好家园
下联：________________________                                     
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阅读理解
阅读理解。
     根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为
多余选项。
     One of the favorite foods in the United States is the hamburger, a kind of flat round bread with
fine-cut beef in between.  1  . At fast food restaurants, people order their food, wait a few minutes to get
it over the counter, and carry it to their tables themselves.   2   .At some fast food restaurants , people
can order their food, pay for it and pick it up without leaving their cars.
       3  . Most of the restaurants sell hamburgers or other popular foods among Americans, In addition,
there are many fast food restaurants that serve Chinese food, Italian food, chicken, seafood and
ice-cream. The idea of a fast food restaurant is so popular that nearly every kind of food can be found in
one.
      4  . First , they are not formal restaurants. People wear any type of dress when they go to a fast food
place. Second, they are fast. People who are busy do not want to spend time preparing their food or
waiting while someone else prepares it.  5  . Finally , most food in a fast food restaurant is not expensive.
Therefore, people can often eat at a fast food restaurant without spending too much money, while they
may not be able to go to more expensive restaurants very often.
A. There are many kinds of fast food restaurants in the United States.
B. People can have almost every kind of food in fast food restaurants.
C. Fast food restaurants are popular because they show the American way of life,
D. The favorite place to buy a hamburger is a fast food restaurant.
E. People also take their food out of the restaurant and eat it in their cars or in their homes.
F. American people go to more expensive restaurant very often
G.  In fast food restaurants the food is usually ready before the customer even orders it.
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