A)根据自身情况回答下列问题 101. When do you get up every day? 102. How do you go to school every day? 103. With whom do you go to school every day? 104. How far is it from your home to your school? 105. What do you do after school every day B)健康的生活习惯在我们成长中至关重要的.你认为健康的生活习惯应该是什么样子的?请根据下面的信息提示.写一篇短文.首句已经给出. 信息提示:1. healthy eating habits 2. go to bed early and get up early 3. take more exercise I think healthy habits are very important for us. 查看更多

 

题目列表(包括答案和解析)

(8分)材料   苏云金芽孢杆菌生长到一定阶段,菌体内一端形成芽孢,另一端形成一种被称为伴孢晶体的蛋白质晶体。菌体破裂后释放出芽孢和伴孢晶体,伴孢晶体本身并无毒性,是毒素的前体。当昆虫吞食伴孢晶体后,在肠道内碱性环境条件和特定的蛋白酶的作用下,伴孢晶体变成毒素分子,能使小肠上皮细胞萎缩退化,昆虫停食,最后脱水死亡。科学家利用苏云金芽孢杆菌的这个特性,在实验室大量培养,制成生物农药,洒在农作物上,让害虫吃后中毒死亡。或利用基因工程技术,把苏云金芽孢杆菌的抗虫基因转到农作物体内,培育出抗虫品种。请根据上述材料回答下列问题:

(1)上图中,切断a处的工具酶是____________ ,切断b处的酶是             ______。
(2)作为目的基因载体的细菌质粒往往要带有一个抗生素抗性基因,该抗性基因在基因工程中主要用于_____________________________________________________。
(3)苏云金芽孢杆菌的抗虫基因导入棉花细胞是否表达,最简便的检测方法是________________________________________________。
(4)苏云金芽孢杆菌的抗虫基因转到农作物体内后,也能产生伴孢晶体蛋白,说明___________________________。
(5)转基因工程改良动植物品种,最突出的优点是_____________________________ 。
(6)大面积种植抗虫棉对该地区生态平衡会造成怎样的影响?                                                   
①________________                       _____________
②_____________________                          _____。

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 阅读短文,根据要求完成下面各小题。

In the past twenty years, riding bicycles has become more and more popular among people of all ages. 83 Bicycles have long played an important part in the liyes of American young people. But today an even greater number of adults cycle along roadsides and bicycle paths. These new riders are often trying to become fit or lose weight. They have found that bicycling is a pleasant way to stay healthy

This is certainly good for health. But it has also brought some problems. With all these added people on the road, bicycle safety has become a matter of real importance.

Bicycle safety is mostly a matter of common sense. People should ride only on bicycle paths where they will not be badly hurt. There are also a number of rules that riders should follow, especially when riding on streets or highways. Bicyclists should never ride against the traffic,nor should they carry other people on their bicycles. They are also supposed to ride in single line on busy streets and to "walk bicycles across the busy intersections (交叉路口) . 84By following these rules, bicycle riders will not only stay healthy but also be safe.

In one recent year, the National Safety Council reported that 34 thousand bicycle riders were hurt in highway accidents. In that same year, another six hundred riders were killed. Since the introduction of crash helmets (头盔) in 1980, the number of injuries (伤者) and deaths from bicycling accidents had gone down. Today, more and more riders realize the dangers of bicycling. They are wearing helmets and paying closer attention to cycling rules.

A.   根据短文内容回答下列问题。

1.How many rules should the riders follow? Give one example.

_______________________________________________________________

2. According to the National Safety Council's report, what's the total number of injuries and deaths in one recent year?

________________________________________________________________

B. 将短文中划线部分译成汉语。

3._______________________________________________________________

4.________________________________________________________________

C. 请给短文拟一个适当的英文标题。

5.________________________________________

 

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阿司匹林(乙酰水杨酸)已应用百年,成为医药史上三大经典药物之一,至今它仍是世界上应用最广泛的解热、镇痛和抗炎药,也是作为比较和评价其他药物的标准制剂。乙酰水杨酸受热易分解,分解温度为128~135℃。某学习小组在实验室以水杨酸(邻羟基苯甲酸)与醋酸酐[(CH3CO)2O]为主要原料合成该物质,设计的合成路线为:
一、制备K
s*5u
二、提纯
方案1
方案2
主要试剂和产品的物理常数
名    称
相对分子质量
熔点或沸点(0C)



水杨酸
138
158(熔点)
微溶
易溶
易溶
醋酸酐
102
139.4(沸点)
反应
可溶
易溶
乙酰水杨酸
180
135(熔点)
微溶
可溶
微溶
请根据以上信息回答下列问题:                   
(1)①合成阿斯匹林时,还会生成一些副产品,其中有一种是高分子,为了分离此物质,方案1中加入A物质为      溶液。
②本方案抽滤后进行洗涤,其具体操作是       
(2)方案2为改进的提纯方法,称为重结晶提纯法。
①该方案中步骤1除了选用乙酸乙酯外,还可选择下列哪些
试剂      
A. 乙醇      B. 蒸馏水      C. 乙醚   
②步骤2回流的装置如图所示,写出仪器a的名称      ,使用温度计的目的是      ,冷凝水的流向为       

③方案2所得产品的有机杂质要比方案1少的原因是      
(3)该学习小组在实验中原料用量:2.0g水杨酸、5.0ml醋酸酐(ρ=1.08g·cm-3),
最终称量产品m="2.2g" ,则乙酰水杨酸的产率为       。

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阅读短文,根据要求完成下面各小题。
In the past twenty years, riding bicycles has become more and more popular among people of all ages. 83 Bicycles have long played an important part in the liyes of American young people. But today an even greater number of adults cycle along roadsides and bicycle paths. These new riders are often trying to become fit or lose weight. They have found that bicycling is a pleasant way to stay healthy
This is certainly good for health. But it has also brought some problems. With all these added people on the road, bicycle safety has become a matter of real importance.
Bicycle safety is mostly a matter of common sense. People should ride only on bicycle paths where they will not be badly hurt. There are also a number of rules that riders should follow, especially when riding on streets or highways. Bicyclists should never ride against the traffic,nor should they carry other people on their bicycles. They are also supposed to ride in single line on busy streets and to "walk bicycles across the busy intersections (交叉路口) . 84By following these rules, bicycle riders will not only stay healthy but also be safe.
In one recent year, the National Safety Council reported that 34 thousand bicycle riders were hurt in highway accidents. In that same year, another six hundred riders were killed. Since the introduction of crash helmets (头盔) in 1980, the number of injuries (伤者) and deaths from bicycling accidents had gone down. Today, more and more riders realize the dangers of bicycling. They are wearing helmets and paying closer attention to cycling rules.
A.  根据短文内容回答下列问题。
【小题1】How many rules should the riders follow? Give one example.
_______________________________________________________________
【小题2】 According to the National Safety Council's report, what's the total number of injuries and deaths in one recent year?
________________________________________________________________
B. 将短文中划线部分译成汉语。
【小题3】_______________________________________________________________
【小题4】________________________________________________________________
C. 请给短文拟一个适当的英文标题。
【小题5】________________________________________

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(8分)材料   苏云金芽孢杆菌生长到一定阶段,菌体内一端形成芽孢,另一端形成一种被称为伴孢晶体的蛋白质晶体。菌体破裂后释放出芽孢和伴孢晶体,伴孢晶体本身并无毒性,是毒素的前体。当昆虫吞食伴孢晶体后,在肠道内碱性环境条件和特定的蛋白酶的作用下,伴孢晶体变成毒素分子,能使小肠上皮细胞萎缩退化,昆虫停食,最后脱水死亡。科学家利用苏云金芽孢杆菌的这个特性,在实验室大量培养,制成生物农药,洒在农作物上,让害虫吃后中毒死亡。或利用基因工程技术,把苏云金芽孢杆菌的抗虫基因转到农作物体内,培育出抗虫品种。请根据上述材料回答下列问题:

(1)上图中,切断a处的工具酶是____________ ,切断b处的酶是             ______。
(2)作为目的基因载体的细菌质粒往往要带有一个抗生素抗性基因,该抗性基因在基因工程中主要用于_____________________________________________________。
(3)苏云金芽孢杆菌的抗虫基因导入棉花细胞是否表达,最简便的检测方法是________________________________________________。
(4)苏云金芽孢杆菌的抗虫基因转到农作物体内后,也能产生伴孢晶体蛋白,说明___________________________。
(5)转基因工程改良动植物品种,最突出的优点是_____________________________ 。
(6)大面积种植抗虫棉对该地区生态平衡会造成怎样的影响?                                                   
①________________                       _____________
②_____________________                          _____。

查看答案和解析>>


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