高一生物酶与酶促反应教学案016（精选五篇）

第一篇：高一生物酶与酶促反应教学案016

4.1.2酶与酶促反应

高一生物教学案016 遭到破坏，而失去活性。课型：新授课 编号 016 时间 2012.10.24（2）该实验中能否将斐林试剂改成碘液？

提示：该实验中不能用碘液代替斐林试剂，因为碘液只能使淀

粉变蓝，而与还原性糖没有特殊的颜色反应，不能检验蔗糖是第 十一 周 第 二 课时 总第 016 课时

否被淀粉酶水解。

备课组长签字： 宋双锋 段长签字：（3）实验中两支试管保温时，温度应控制在什么范围内？若改主备人：崔志民 一 年级 生物 备课组

A．生物体内的酶不是都由活细胞产生的B．活的生物体的任何一个细胞都能产生酶，酶只有在细胞内才能起催化作用 C．绝大多数酶是在核糖体上合成的，生物体缺乏某种酶就可能出现这种酶缺乏症 D．同一生物体内的各种酶要求的催化条件都相同，其催化效率姓名： 层次：

一、学习目标

1、酶的作用和本质。

2、酶的特性。

3、酶促反应和影响酶促反应的因素。

二、学习重点

1、酶的作用和本质。

2、酶的特性。

3、酶促反应和影响酶促反应的因素。

三、学习难点

1、酶促反应和影响酶促反应的因素。

四、使用说明 1．自学课本，从第55页到第58页，用红笔画出疑难点，2.完成教学案填空内容，习题。

五、教学流程

课程导入：吃馒头时我们会感到甜，而我们吃富含纤维素的蔬菜时却感觉不到甜味，试分析其原因？

【自主学习A级】探究

一、酶的作用及本质

1.酶是指由活细胞产生的、具有催化活性的一类特殊蛋白质，生物体内所有化学反应都需要酶的参与，那么酶是否一定在细胞内发挥作用呢？

提示：不是。无论是在细胞内还是细胞外，只要条件适宜酶都能起催化作用。

2.请结合教材中酶具有催化性的实践活动，思考下列问题：

（1）实验中选用蒸馏水的目的是什么？

提示：实验中设置加入蒸馏水的试管做对照组，目的是增强实验结论的说服力。

（2）酶催化的反应中，酶能否使生成物的量增加？

提示：不能。酶只能降低化学反应的活化能，加快反应速度，缩短达到平衡的时间，但不会使生成物的量增加。

3.结合教材中酶具有特异性的实践活动，讨论下列问题：

（1）进行实验时，要使用完全冷却的淀粉溶液，而不能用刚煮沸的淀粉溶液，原因是什么？

提示：若用刚煮沸的淀粉溶液进行实验，淀粉酶会因温度过高

用唾液中的唾液淀粉酶来催化该反应，温度控制范围和前者相受温度和pH的影响 同吗？

解析

提示：两支试管保温时，应控制在60 ℃左右，因为60 ℃是该（1）酶是活细胞产生的具有催化活性的一类特殊蛋白质。种淀粉酶的最适温度，低于或高于此温度，都会降低化学反应（2）不同种类的酶作用条件是不同的，但只要它们的结构不变，的速率。若改用唾液中的唾液淀粉酶来催化该反应进行，温度

且条件适宜，都能正常发挥作用。

就要控制在37 ℃左右，因为唾液淀粉酶的最适温度是人的体A错误，酶是由活细胞产生的；B错误，活细胞能产生酶，有温，即37 ℃左右。的酶在细胞内起作用（如呼吸酶），有的酶在细胞外起作用（如4.根据如图曲线试总结酶与无机催化剂的相同点和不同点。

消化酶）；C正确，绝大多数酶属于蛋白质，是在核糖体上合成 的，生物体缺乏某种酶就会影响机体内的某一化学反应，可能

出现这种酶缺乏症，如缺少酪氨酸酶引起白化病；D错误，同提示：（1）相同点：都能加快化一生物体内不同的酶要求的催化条件可以不同，如胃蛋白酶、学反应的速率，缩短反应完成的胰蛋白酶所需的最适pH相差很大。

时间。

【自主学习B级】探究

二、影响酶促反应的因素

（2）不同点：酶与无机催化剂相

1． 在日常生活中，使用加酶洗衣粉要比使用普通洗衣粉更容比，催化效率更高。

易清除衣物上的奶渍、油渍，为什么？使用加酶洗衣粉时，最点拨

好用温水浸泡，为什么?

1．酶概念的三要素

提示：加酶洗衣粉中含有一部分酶，比如脂肪酶、蛋白酶等，（1）来源：活细胞产生的。死细胞不产生酶，凡是活细胞一定

它们能够分解脂肪、蛋白质，使之变成小分子的物质，更加容都能产生酶。

易清洗。酶的作用需要适宜的温度条件。

（2）生理作用：催化作用。酶是生物催化剂。

2.当人发烧时会感到全身不适、无力、食欲不振，试从酶的作用（3）化学本质：有机物。绝大多数酶是蛋白质，极少数酶是

角度分析产生这些现象的原因。

RNA。

提示：高温使体内酶（包括消化酶）的活性降低，消化能力减2.酶的作用部位

弱，所以食欲不振。

细胞内或细胞外。

3.酶的作用机理

酶在化学反应中起的催化作用，主要是降低了反应的活化能，酶在反应前后质量和性质不变化。酶只能催化原本能进行的反

应，而不能催化原本不能进行的反应。

4.在探究酶具有催化性的实验中，判断反应进行程度的两种方法

（1）气泡目测法：观察反应产生的气泡数量。

（2）火星复燃法：观察带火星卫生香复燃的剧烈程度。

例

1、下列关于酶的叙述中正确的是 1 【特别提醒】①低温和高温时酶的活性都降低，但两者的性质A．特异性

不同。②在过酸或过碱环境中，酶均失去活性而不能恢复。③B．不具备催化剂的一般特征 同一种酶在不同pH下活性不同，不同的酶的最适pH不同。④C．高效性

反应溶液酸碱度的变化不影响酶作用的最适温度。D．在温和条件下进行

例

2、如图曲线表示的是温度和酶活性的关系，此曲线不能说(B)3.（2011·昆明高一检测）酶具有很强的催化功能，其原因明的是 是（）

A.显著降低了化学反应所需的活化能

B.增加了反应物之间的接触面积

C.显著提高了化学反应所需的活化能 A.不同的温度D.减小了反应物之间的接触面积

范围内酶的活(B)4.多酶片中含有蛋白酶、淀粉酶、脂肪酶，性不同

具有辅助消化的作用，其片剂是糖衣片，B.当温度达到B时，酶的活性最高

这样制作的目的是（）C.A点时，酶的催化活性很低，但随着温度升高，酶的活性可A.补充体内糖类物质的供应 以上升

B.防止胃液的消化作用

D.C点时酶的活性也很低，当温度降低时，酶的活性也可以恢C.经唾液的消化作用后可迅速起作用 复上升 D.使其中各种酶缓慢地释放

解析

(C)5.（2011·盐城高一检测）两个学生在研究温度对两种天然解题时应明确高温、低温对酶活性的影响是不同的。低温抑制酶（能催化同一种反应）的作用后绘制了如下数据图。观察他酶的活性，而高温破坏了酶的结构，能使酶失活。

们的数据图，回答问题： 从图中可以看出随着温度的不断升高，酶的催化活性在上升，等达到B点时，酶的催化活性达到最高，随着温度的继续上升，酶的催化活性迅速下降。但是A点和C点相比，虽然酶的催化 活性都很低，但是A点是低温条件，对酶分子结构无影响，随 着温度的上升，其催化活性可不断上升，而C点是高温条件，当温度过高时，会破坏酶的分子结构，使酶的活性发生不可逆 的变化。

当堂检测

(A)1.关于酶生理功能的叙述，下列哪一项是正确的（）

A.能为生物体内的化学反应提供能量

B.具有催化作用，比无机催化剂的催化效率高得多

C.酶与无机催化剂降低反应活化能的效率相同(1)酶A的最适温度是_____，两种酶催化的反应速率相等的温D.能促进生物体内营养物质的运输 度约是___________。

(2.)根据如图所示过氧化氢(2)可能来自于热泉中的细菌体内的酶是分解速率的曲线，说明酶的___________。

哪一特性（）(3)在0～80 ℃的温度范围内，随温度的升高，酶B 的活性___________。

(4)如果先将酶B置于100 ℃的温度下，然后逐渐降

低温度，反应速率不变，原

因是

____________________________。小结：

作业布置： 完成此教学案并上交

课后反思：（学生写学后反思，教师写教后反思）

1、成功之处

2、不足之处

3、改进措施

出勤情况：

板书设计：

复备区 复备人：

例1C 例2D

1、B

2、C

3、A

4、B

5、答案：（1）40 ℃

℃

（2）酶B（3）逐渐升高

（4）酶在100 ℃时已失活

第二篇：酶与酶促反应教学设计

酶与酶促反应教学设计

李培花 静待花开一生物学科工作坊

（作者简介：李培花，女，汉族，生于1986年，现任教于横山中学，二级教师。2009年7月毕业于延安大学，特岗教师，2010年开始担任高中生物教学。性格开朗，心直口快；积极乐观，勤勉刻苦；默默无闻；兢兢业业；治学严谨，教学有方，诲人不倦。）

一、教材分析

“酶与酶促反应”是苏教版“分子与细胞”的第四章第一节内容。前面已学习已经认识了细胞的结构和物质基础，但没有接触细胞的代谢。本节内容是在学生学习了酶的定义和ATP相关内容的基础上进行的，进一步深入了解酶的高效性、专一性和酶的作用条件温和。同时穿插实验的设计、实验变量的判断、实验设计的原则，并能简单分析实验现象，为下节课探究影响酶促反应速率的因素做铺垫。

二、教学设计思路

运用旧知识导入法，让学生回忆酶的定义和酶具有催化性实验，提出问题：酶具有催化性，那么它的催化机理是什么呢？它还有什么性质呢？进入本节新课的研学。首先让学生阅读课本66页的“知识海洋”结合导学案的6、7内容思考：

1、什么是活化能？

2、PPT中曲线中的CA和CB的含义是什么？然后师生共同分析得出酶具有催化的实质是降低了化学反应的活化能。同时质疑：无机催化剂和酶都有催化性，那么谁得催化效率更高呢？接着让学生结合导学案8和PPT所示内容，分析实验现象进而得出实验结论：酶具有高效性。尝试分析导学案9的曲线，师生总结得出高效性的实质和意义。其次开始讲述酶的另一特性----专一性，结合课本的“酶具有专一性”实验，设置问题，让学生探讨理解专一性的含义，最后以加酶洗衣粉的使用温度得出酶的作用条件温和这一特性。

三、教学目标

1、通过实验认识酶的高效性和专一性，根据相曲线进一步理解酶高效性的实质。

2、通过学生阅读教材、导学案相关内容，尝试分析实验中的自变量和因变量，初步掌握控制变量的方法并尝试设计实验。

3、将生物核心素养----科学探究的方法：观察法、实验法和资料分析法渗透在教学过程中。

四、教学重难点

1、教学重点：酶的高效性和专一性的实验设计分析。

2、教学难点：酶的高效性实质的理解，专一性的实验设计分析。

五、课前准备

PPT、导学案

六、教学过程

（一）、导课 旧知识导入法

利用学生已学习的酶的定义，共同回忆其来源、作用和本质以及验证催化性的实验过程，然后质疑：酶的催化机理是什么？进入新课研学

（二）、新课

1、酶的高效性

活动安排;(1)、学生阅读66页内容的“知识海洋”，结合导学案的6、7，明确活化能的含义，对照曲线：尝试说出ca、cb、ba段的含义（图一）

（2）教师引导学生得出酶催化性的机理是降低了化学反应的活化能。（图二）

（3）教师PPT展示图片及相关数据帮助学生理解酶的高效性

知识过度：我们都有这样的体会：吃馒头时，越嚼越甜，那是因为唾液中含有唾液淀粉酶可以使淀粉水解，所以馒头变甜。但是吃肉时不小心把肉丝卡在牙缝里了，结果两天后他还有被消化，为什么？导出酶的特异性（专一性）

2、酶的特异性

活动安排：（1）PPT展示酶的特异性的概念，学生阅读66页内容的理解特异性的含义。

（2）教师引导如何设计验证酶的特异性实验。

设计思路：酶相同底物不同或者底物相同酶不同

（3）学生阅读课本65页实验，分析讨论PPT所示的问题：

（4）老师根据学生的回答对其进行点评，补充，最后得出实验结论：淀粉酶只能催化淀粉水解，对蔗糖不起作用，则酶具有特异性。

3、作用条件温和

教师从学生熟悉的加酶洗衣粉作为切入点，询问用怎样的水温洗的衣服更加干净？然后PPT展示酶的另一个性质，作用条件温和，以及其意义。酶需要在常温、常压和适宜的温度，正好符合生物体内的生活环境。

（三）课堂小结

师生边回忆边完成知识框架

七、板书设计

二、酶的性质

1、催化性 活化能含义

2、高效性

实质：降低了反应的活化能

3、特异性（专一性）：（一种酶只催化一种底物的分解）

4、作用条件温和

第三篇：【典型题】酶促反应速率问题的研究

[2003年上海高考生物第11题]下图纵轴为酶反应速度，横轴为底物浓度，其中正确表示酶量增加1倍时，底物浓度和反应速度关系的是

命题者提供的参考答案是B。但在K12生物论坛的讨论中，很多老师认为应该选A。也有老师说虽然知道应该选B，但总觉得理由不充分。笔者认为，要正确理解这道题目，首先是必须弄懂酶促反应速度（题目中如此，其实正确的说法，应该称为“酶促反应速率”）的含义，其次要有酶促反应的动力学的有关知识作为基础。下面，笔者先把那些认为应该选A的老师提出的理由整理出来，然后介绍酶促反应速率的含义以及酶促反应的动力学的有关知识，并在此基础上阐述该题正确答案是B的理由。1 许多老师错误地选A的理由

先观察A、B选项中任何一条曲线，曲线的前半段，随横坐标底物浓度的增加，纵坐标酶促反应速度也增加，说明底物浓度是此时反应速度增加的限制因素。此时，即使增加酶量也不会使反应速度也增加。而曲线的后半段反应速度不再随底物浓度变化而变化，说明底物足够，此时底物浓度已不是反应速度增加的限制因素了；此时，酶的数量则相对不足，此时增加酶量会使反应速度加快。综上所述，正确的曲线应该是最初两条曲线重合，底物浓度足够多时才能体现出酶的数量对反应速度的影响。2 酶促反应速率的概念

酶促反应的速率（v），一般是以单位时间内底物被分解的量来表示的。假设x克蔗糖在t时间内被一定的蔗糖酶水解为葡萄糖和果糖，则x/t即为蔗糖酶反应的速率。

酶促反应在开始的初期速率较大，一定时间后，由于反应产物浓度逐渐增加，反应速率渐渐下降，最后完全停止。如果底物浓度相当大，而pH及温度又保持恒定，则在反应初期的一定短时限内，酶的反应速率尚不受反应产物的影响，可以保持不变。故测酶的反应速率一般只测反应开始后的初速，而不是测反应达到平衡时所需要的时间。3 酶促反应的动力学（影响酶反应的因素）的相应知识

酶促反应的速率是受酶浓度、底物浓度、pH、温度、反应产物、变构效应、活化剂和抑制剂等因素的影响的。下面仅讨论与此题有关的酶浓度和底物浓度的影响。3.1 酶浓度的影响

在有足够底物的情况下，而又不受其他因素的影响，则酶的反应速率（v）与酶浓度成正比。即

v=k[E]………………………………（1）k为反应速率常数，[E]为酶浓度。

因为有底物足够的条件，因此，对任一酶浓度[E]，由（1）式求出的酶的反应速率v应当就是在该酶浓度下的最大反应速率Vmax。3.2 底物浓度的影响（米氏方程）

实验证明：当酶浓度、温度和pH恒定时，在底物浓度很低的范围内，反应初速与底物浓度成正比；此后，随着底物浓度的增加，反应速率的增加量逐渐减少；最后，当底物浓度增加到一定量时，反应速率达到一最大值Vmax，此时再增加底物浓度也不能使反应速率再增加。1931年，Michaelis与Menten根据中间产物理论提出了能表示整个反应中底物浓度与反应速率关系的公式，称Michaelis-Menten方程或简称米氏方程： v=Vmax[S]/（Km+[S]）………………（2）

公式中，v为反应速率，Vmax为最大速率，Km为米氏常数。

Km是酶的特征常数之一，在数值上等于酶促反应速率达到最大速率一半（v=Vmax/2）时的底物浓度，单位为mol/L。4 正确答案是B的理由

对于底物浓度较大时，增加酶量可以增大反应速率这一结论，大家都没有异议。现在大家争议的焦点，就是在底物浓度很小时，增加酶量能否增大反应速率？对于这一问题的不同回答，决定上述高考题的答案选择：如果回答是肯定的，那么此题的正确答案是B；反之，正确答案就是A了。下面笔者为大家仔细分析一下这个问题。

上述题目中只涉及一种酶，从上面引述的酶促反应的动力学的相关知识中我们看到，对于同一种酶来说，Km为定值。题目中涉及的酶浓度有2种，从上面引述的酶促反应的动力学的相关知识中我们看到，酶的最大反应速率Vmax与酶浓度[E]成正比。而根据米氏方程，酶的反应速率v与最大速率Vmax成正比。由此我们可以得出结论：在底物浓度一定时，酶促反应速率v与酶浓度[E]成正比。即使在底物浓度[S]很小时，酶的浓度不同，反应速率也不会相同。酶的浓度增加1倍，反应速率也会相应增加1倍。

这样看来，上面这道题只能选B，不能选A，理由是很充足的哦！5 从中学生物范围内怎样理解这道题

从上述分析中我们看到，要透彻理解这道，需要有关酶促反应的动力学方面的基础知识，而这些知识是中学教材中没有涉及到的，甚至中学生物教师用书上也没有。因此，尽管这道题并没有什么错误（“反应速度”的提法不妥除外），但有超纲之嫌。

如果要求在中学生物知识的范围内，对这一道题作出合理的解答，确实比较困难。下面推荐K12生物论坛中一些老师提出的解释：这个题目中影响整体反应速度的因素有两个：一是底物浓度，一是酶的浓度。所以当底物浓度不变时，酶的浓度决定反应速度；当酶的浓度不变时，底物浓度决定反应速度。两个浓度都变时，共同决定反应速度。老实说，笔者尽管倾向于支持上述说法，但也觉得它无法圆满解释在底物浓度很低的情况下，为什么增加酶量能够加快反应速度。所以笔者想，这可能也算是一个没有办法的办法罢。12月19日补记：最近又有人在K12论坛上讨论这个试题，网友“小黑牛”提出了下列观点，似乎有利于在中学知识范围内解释清楚这个试题：中间产物学说（E+S-----ES-------E+C+D）认为，酶也是反应物，只是在这样的反应中，反应了的酶又能重新生成。由于酶也是反应物，所以增加反应物浓度或增加酶的浓度，反应速率都会增大。参考文献： 郑集：普通生物化学，人民教育出版社 张玉中、阎一林：基础生物化学问答，科学普及出版社

（2011上海高考）下图实线表示联苯水解酶催化的反应速率与酶浓度的关系，虚线表示在其他条件不变的情况下，底物浓度增加一倍，反应速度与酶浓度的关系，能正确表示两者关系的是（）

答案：B

第四篇：二酶的特性 教学案

酶的特性 教案

唐山市迁西县第二中学 裴金利

【教学目标】

1、知识目标

（1）理解酶在细胞代谢中的特性。

（2）理解影响酶活性的条件。

2、能力目标：

4、实验设计

（1）实验预期：根据自己作出的假设，预期会看见怎样的实验结果？并做记录。

通过实验，掌握酶的活性受温度、PH值的影响。

3、情感目标：

通过实验，感受科学的严谨性。【教学重点】

影响酶活性的条件实验、酶的特性。【教学难点】

影响酶活性的条件实验。

【教学用具】PPT课件、多媒体、教学案

【教学方法】结合学案进行教学，主要采用自学指导法、分组讨论法、练习法、演示法讲述法等。【教学时数】2课时

第一课时

一、酶的高效性

大量实验证明，酶的催化效率大约是无机催化剂的__________倍。

二、酶的专一性

每种酶只能催化___________化学反应，如过氧化氢酶只能催化过氧化氢的分解，脲酶只能催化尿素的分解。细胞代谢能够有条不紊地进行，与__________是分不开的。

三、探究影响酶活性的条件

酶活性：酶对化学反应的催化效率称为酶活性。

（一）PH对酶活性的影响探究

1、提出问题：

2、作出假设：

3、材料用具：

（2）本实验的自变量是什么？因变量是什么？用什么方法控制自变量？（3）对照组怎样设置？你将设定哪几个PH？怎样将不同溶液的PH分别调到设定

5、实验方法

6、实验结果： 结论：

（二）温度对酶活性的影响探究、提出问题：、作出假设：、材料用具：

的数值？

4、实验设计

（1）实验预期：根据自己作出的假设，预期会看见怎样的实验结果？并做记录。

（2）本实验的自变量是什么？因变量是什么？用什么方法控制自变量？

（3）对照组怎样设置？你将设定哪几个温度？怎样将不同溶液的温度分别调到设定的数值？

5、实验方法

6、实验结果：

结论：

第二课时

四、酶的作用条件较温和

酶所催化的化学反应一般是在____________的条件下进行的。在______________________下，酶的活性最高，温度和pH____________，酶的活性都会_________。

一般来说，动物体内的酶最适温度在___________之间，植物体内的酶最适温度在__________之间，细菌和真菌体内的酶有的最适温度高达________。

动物体内的酶最适pH大多在_________之间，但也有例外，如胃蛋白酶的最适pH为______，植物体内的酶最适评pH大多在____________之间。____________或温度_____，会使_______________遭到破坏，使酶________。0℃左右时，酶的_______，但酶的______________，在适宜的温度下酶的活性可以_______。因此酶制剂适于在________________下保存。

【课堂练习】

1、关于酶的特性，下列表述中错误的是（）A、酶是活细胞产生的具有催化能力的有机物 B、化学反应前后，酶的化学性质和数量不变

C、酶的催化效率很高，但易受温度和酸碱度影响 D、一旦离开活细胞，酶就失去催化能力

2、用纯唾液和用稀释10倍的唾液做唾液淀粉酶的催化实验，其效果完全相同，这说明酶具有（）

A、专一性 B、多样性 C、高效性 D、多变性

3、能水解脂肪酶的酶是（）A、淀粉酶 B、蛋白酶 C、脂肪酶 D、麦芽糖酶

4、人在发高烧时，常常食欲大减，最根本的原因是（）A.所吃食物不能消化 B.胃没有排空

C.体温超过合适温度，消化酶的活性下降 D.吃药使人没有了胃口

5、胃蛋白酶在进入小肠后就几乎没有了催化作用，主要原因是（）

A.pH不适合 B.胃中已经起了消化作用，不能再起作用了 C.被小肠中的物质包裹起来，所以起不到催化作用 D.小肠中没有蛋白质可被消化 课堂练习

6、下列有关酶的叙述错误的是()

A.组成大多数酶的基本单位是氨基酸 B.少数酶是RNA

C.每种酶都具有高效性，专一性 D.酶都具有消化功能

7、将唾液淀粉酶先放入沸水中2分钟，再放在37℃的恒温水浴中，酶的催化效率前后变化是()A、不断降低 B、先升后降 C、先降后升 D、没有变化

8、加酶洗衣粉中一般含有蛋白酶，请回答下面的问题：（1）这种洗衣粉为什么能够很好地除去衣物上的奶渍和血渍？

（2）使用这种洗衣粉为什么要用温水？

（3）含有蛋白酶的洗衣粉不宜用来洗涤下列哪些衣料？（）A.化纤 B.纯毛 C.纯棉 D.真丝

（4）为了更好地除去衣物上的油渍，在洗衣粉中还可以加入什么酶？

【作业】 1.加酶洗衣粉不能用沸水溶解，这说明了酶的作用（）A．适用低温下催化 B．具有高效性 C．需适宜的温度 D．具有专一性

2.人的血液中碳酸酐酶的1个分子，每分钟可催化1900万个碳酸分子，这说明酶具有（）

A．多样性 B．专一性 C．可控性 D．高效性 3.下列有关酶的叙述正确的是（）

A．都是活细胞产生的，在细胞内起作用

B．酶的产生受遗传物质控制，也可从食物中获取

C．酶是活细胞产生的具有催化作用的有机物，其中绝大多数酶是蛋白质 D．酶在催化过程中不断被消耗 4.下列说法正确的是（）A．酶就是蛋白质

B．由于酶比无机催化剂具有更高的催化速率，所以反应前后本身的数量也减少的多 C．酶的活性与PH、温度等因素有关

D．酶不能脱离生物体起作用

5.能正确说明酶不同于一般催化剂的催化特性之一的是（）A．酶都是蛋白质

B．酶是活细胞产生的，只能在生物体内发挥催化作用 C．酶的活性随着温度升高而不断提高

D．每一种酶只能催化一种或一类物质的化学反应

6.唾液淀粉酶进入胃后就失去其催化作用，主要原因是（）A．酸碱度不适宜 B．胃蛋白酶抑制了唾液淀粉酶的作用 C．胃中没有淀粉 D．唾液淀粉酶被分解

7.研究表明：一分子过氧化氢酶能在1分钟内是5×10个过氧化氢分子分解成氧和水，相当于Fe3+催化速度的109倍，但是对糖的水解却不起作用，这个事实说明酶分别具有（）

A．多样性，稳定性 B．高效性，多样性 C．高效性，专一性 D．高效性，稳定性

8.下图中，横轴均表示酶的反应条件，纵轴为酶促反应速度，能正确反映温度和PH值与酶促反应速度的关系是（）

A．甲和丙 B．甲和乙 C．都是丙 D．都是丁

甲 乙

丙 丁

9.10℃（X）、40℃（Y）、80℃（Z）条件下，人唾液淀粉酶的活性是（）A．X＞Y＞Z B．Z＞Y＞X C．X＞Z＞Y D．Y＞X＞Z 10.分别用0℃和100℃的温度处理淀粉酶后，酶都没有活性，但（）A．经过0℃处理的酶的活性能够恢复 B．经过0℃处理的酶空间结构遭到破坏 C．经过100℃处理的酶的活性能够恢复 D．经过100℃处理的酶被水解成了氨基酸

5【课后反思】

酶的特性实验参考资料

探究影响酶活性的条件

（一）PH对酶活性的影响探究

材料用具：

新鲜的质量分数为20%的肝脏研磨液、质量分数为3%的过氧化氢溶液、质量分数为5%盐酸、质量分数为5%的NaOH溶液、蒸馏水 试管、量筒、滴管、pH试纸 实验方法

（1）取三支试管，编号为1、2、3号，分别加入2mL质量分数为3%的过氧化氢溶液。

（2）取三支试管，编号为1′、2′、3′号，分别加入2mL蒸馏水、质量分数为5%盐酸、质量分数为5%的NaOH溶液，摇匀。

（3）分别把1′号试管液体倒入1号试管、2′号试管液体倒入2号试管、3′号试管液体倒入3号试管，摇匀。

（4）观察这三支试管中产生气泡的情况。

（二）温度对酶活性的影响探究 材料用具

质量分数为2%的新配制的淀粉酶溶液、质量分数为3%的可溶性淀粉溶液、热水、蒸馏水、冰块、碘液

试管、量筒、滴管、烧杯、温度计、试管夹、酒精灯、三角架、石棉网、火柴

实验方法

（1）取三支试管，编号为1、2、3号，分别加入2mL质量分数为3%的可溶性淀粉溶液。

（2）取三支试管，编号为1′、2′、3′号，分别加入质量分数为2%的新配制的淀粉酶溶液。

（3）将装有淀粉溶液和淀粉酶溶液的试管分为三组：1和1′、2和2′、3和3′，分别放入热水（约60℃）、沸水和冰块中，维持各自温度5min。

（4）分别将淀粉酶溶液注入相同温度下的淀粉溶液中，摇匀后，维持各自温度5min。

（5）在三支试管中各滴入1-2滴碘液，摇匀。

（6）观察这三支试管中溶液的颜色变化。

作业答案 1-5CDCCD 6-10ACCDA

第五篇：阅读理解教学案0

阅读理解教学案（理科）

制作人：岳光艳 审核人：明文玲 使用时间：_____ ——课前预习案——

阅读中几种题目的对策: 1）细节事实题：标志：fact（from the fact we could learn）（we learn from the fact that）细节实事题中常见的迷惑手段：单词替换；常识判断；颠倒因果；偷换概念；扩大范围

2）例证题：标志：example,illastration,case/examplify,illastrate,demostrate 返回原文找出该例证（定位）90％向上,10% 向下搜索例证支持的观点3）词汇题：标志：在题干中明确指出原文中某处的单词或词组要求急于解释判断该词是否超纲若未超出大纲则其常见意思必然不是正确答案，其正确答案是根据上下文推测处的一个深刻涵义或生僻涵义若为超纲词或为大多数人不认识的单词，则其字面意思或常见意思就是正确答案。4）句子理解题：标志：在题干中明确提出原文中某处的一个句子要求进行理解。返回原文找出该句，并对其意思进行精确理解，必要时进行语法分析。正确答案是与原句意思最接近最一致的一个选项。

——课中探究案——

Body and Food Your body, which has close relations with the food you eat, is the most important thing you own, so it needs proper treatment and proper nourishment(营养).The old saying “An apple a day keeps the doctor away ” is not as silly as some people think.The body needs fruit and vegetables because they contain vitamin C.Many people take extra vitamins in pill form, believing that these will make them healthy.But a good diet is made up of nourishing food and this gives all the vitamins you need.The body doesn’t need or use extra vitamins, so why waste money on them?

In the modern western world, many people are too busy to bother about eating properly.They throw anything into their stomachs, eating hurriedly and carelessly.The list of illnesses caused or made worse by bad eating habits is frightening.1.“Your body has close relations with the food you eat.”It really means that

.A.all kinds of food you eat can be made into your body B.your body is made up of the food you eat C.what you eat has a great effect on your health D.the more you eat, the fitter you will feel 2.The old saying referred to in the passage tells us that ______.A.eating apples regularly does lots of good to our health B.the apple is the best among all kinds of fruits C.apples can take the place of doctors

D.an apple is a sure cure for illness 3.In the second paragraph, the writer tries to let us know ______.A.our bodies need food or we can’ t live

B.often eating apples is a good habit C.taking vitamin pills is completely useless

D.a good diet is of great importance for our health 4.In the modern western countries ______.A.people don 't want to pay more attention to their eating B.lots of people’ s illnesses are caused or made worse by bad eating habits C.people throw everything into their stomachs without chewing D.people are only too busy to cook meals for themselves

5.From the passage we can draw a conclusion that if we want to keep healthy, we should ______.A.only eat an apple a day

B.eat improperly C.take as many vitamin pills as possible D.throw something into our stomachs slowly and carefully ——课后巩固案——

A

Dear Mr.President, I would like to personally thank you for your time and concern for our great country.I would like to take a few minutes to address a few concerns that I have with the United States.First of all, I would like to address the war.In my opinion, we should have never been involved with Iraq to the extent that we are now.I believe we should pull our troops out.However, I think there should be a timetable that we follow but the timetable should not be released because the enemy does not need to know when we are going to pull out.Also, the war takes out a ton of our money, which leads me to my next issue.The economy right now, in the opinion of many Americans is the biggest issue with which we are facing right now.No one can predict what will happen one day or the next.The obvious thing to do is to put 700 billion dollars in the economy, but that bill failed and was rejected by the House of Representatives.Instead of putting 700 billion dollars in, I think the money should be equally distributed among Americans to pay off their debts.I’m not sure if this would work, but I think it is a positive alternative we could take.My final issue I would like to call to your attention is teachers’ salaries.The high school students of today are America’s future.In a way, America’s future depends greatly on the high school teachers of America.Saying this, it is sad that teachers’ salaries are where they are.While teachers are working harder and harder every day to teach high school students, CEOs of big companies that are driving our country’s economy into the ground are getting bonuses.I’m not saying that teachers’ salaries should be the same of CEOs of companies, but I do strongly believe that action should be taken to increase the salaries of teachers because they have one of the most important jobs in America---preparing our country for the future.Once again, thank you for your time and your effort you put into making this great country a better place.Sincerely, Walker 1.What’s the author’s attitude towards the Iraq War?

A.Supportive

B.Objective

C.Negative D.Positive 2.What’s true about the time of pulling the troops out?

A.We should pull the troops out without delay.B.There is no need to have a timetable to follow.C.The public has the right to know the timetable.D.We should keep the time secret from the enemy.3.According to the author, the 700 billion dollars ______________ A.is the biggest issue with which we are facing right now.B.has been accepted by the House of Representatives.C.should be equally shared among Americans.D.should be put in the economy.4.When talking about high school teachers, the author thinks that _______________ A.the teachers’ salaries are not high enough.B.the teachers’ salaries should be as high as CEOs’.C.the teachers work harder than CEOs of companies.D.teaching is more important than any other job in America.5.Which of the topics is NOT included in the letter? A.Election

B.International affair

C.Finance D.Education

B Not too long ago, our teacher, being a “tree-hugger”(as the kids call her), had us write an essay on an environmental issue.I was eager to start, but something made me stop.“What is an environmental issue ?” one kid asked.“What if we don’t care about the environment ?” another complained.“ It’s not like it affects me.”

These comments astounded me.I have always cared about the environment and assumed that others did too.From the surprised look on my teacher’s face, I could tell she felt the same way.In no time, I finished my essay.In my essay I wrote about logging(伐木), which is an important industry, but if we continue to cut down trees without replacing them, it will damage the environment.There are so many things that we can do to save our world.Recycling, of course, is always a good thing, but not everyone has a recycling plant nearby(I don’t).There are other ways to help the environment.Plant a tree.Don’t waste water.I can’t stand it when a person’s excuse for not caring is “Nothing’s going to happen in my lifetime, so why should I care ?” Sure, the chances of something terrible happening are slim, but I want people to realize that if we don’t deal with it, someone will have to eventually.Do you want that to be your children ?

When my teacher told me to read my essay to my class, I was a little embarrassment because I didn’t want everyone to call me “tree-hugger”.I realize now that if being a tree-hugger means you cares about the environment, I’m a tree-hugger 100 percent.I just wish more people were too.1.Why do the students call her teacher “tree-hugger” ?

A．She likes hugging trees.B．She knows a lot about trees.C．She grew up in the country.D．She cares a lot about the environment.2.The underlined word in Paragraph 3 can be replaced by ____.A．helped B．changed C．shocked D．interested 3.Paragraph 5 is mainly about ____.A．what we can recycle

B．how we can save the earth C．why we should protect the earth

D．what damage we are doing to the earth 4.We can infer from the text that _____

A．the students don’t like the teacher

B．the teacher liked the author’s essay C．the author is ashamed of being a tree-hugger D．the author should have written a better essay

C Here is a true story about a famous man who worked in the White House and a criminal.They once faced the same thing: their mother gave them apples when they were young.The criminal said: one day, my mother brought some apples and asked my brother and me: “Which do you want?” “The reddest and biggest one,” my little brother said.My mother stared at him and said to him angrily: “You should learn to give the good things to others;you shouldn’t always think of yourself.” Seeing this, I suddenly changed my idea and then said to my mother: “Mum, please give me the smaller one and give the bigger one to my little brother.” Hearing my words, my mother was very happy.She kissed me on my face and gave the reddest and biggest apple to me as a prize.From then on, I learned to tell lies, fight, steal and rob.In order to get what I wanted, I played hard.As a result, I was sent into prison.The famous man from the White House said: One day, my mother brought some apples.She said to my brother and me: “You all want the reddest and biggest one, right? Well, let’s have a competition.Now I divide the grassland in front of the gate into two and I will give one to each of you and you must shear(修剪)it well.And I will give the reddest and biggest apple to him who does it the most quickly and best.”

After the competition, I won and I got the biggest apple.In our family, as long as you want to get the best things, you must take part in competition.I think it is fair.No matter what you want, you must pay lots of efforts.1.The criminal got the reddest and biggest apple because ______.A．he told the truth that he wanted a smaller one B．his mother loved him more than she loved the younger brother C．elder brother should of course have the bigger one D．he knew how to make his mother happy from her answer 2.We can conclude from the passage that______.A．it’s important to make children aware that no matter what they want, they must pay work B．it’s wrong to ask children to choose apples when they are not old enough C．it’s wrong to ask children not to always think of themselves

D．it’s always necessary to have a competition when we give children apple 3.The writer tells the story by_____.A．organizing it in the order of time B．making a comparison between two men C．providing some scientific information D．describing it in the order of space 4.It is implied in the passage that______.A．we should always try to win competitions which can bring us a lot B．in order to get what we want, we should play hard C．giving children apples will lead them to become criminals D．a mother’s educational method has a great influence on a child’s growing

【小题1】Which of the following is true of the membership card? A．Its number is l0865 305305.B．It belongs to Mr.E.M.Driscoll.C．It is valid through the year of 2010.D．It gets the owner a discount when used.【小题2】If one wants to attend a business lunch in London at l2：00,the latest train that he should take at Oxford leaves at.A．11：45 B．11：15 C．10：35 D．10：05 【小题3】If you would like to have some vegetable beef, what may be your choice? A．French Slam®

B．Chicken-Fried Steak® C．The Super Bird® D．Sandwich with Salad or Soup® 【小题4】The chart shows that from 2005 to 2008，A．the percentage of the Spanish families with a computer rose 35 points B．the percentage of the White families with a computer remained unchanged C．the number of the Black families with a computer was on the decrease D．the number of the Asian families with a computer showed the sharpest increase 【答案】

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标题/来源：2013-2014学年河北石家庄无极中学高二上期第一次月考英语卷（带解析），日期：2013/11/4 【题文】One day an out of work mimic(滑稽演员)is visiting the zoo and attempts to earn some money as a street performer.As soon as he starts to draw the crowd，a zoo keeper grabs him and drags him into his office.The zoo keeper explains to the mimic that the zoo's most popular attraction，a gorilla(大猩猩)，has died suddenly and the keeper fears that attendance at the zoo will fall off.He offers the mimic a job to dress up as the gorilla until they can get another one.The mimic accepts.So the next morning the mimic puts on the gorilla suit and enters the cage before the crowd comes.He discovers that it's a great job.He can sleep all he wants，play and make fun of people and he draws bigger crowds than he ever did as a mimic.However，eventually the crowds tire of him and he tires of just swinging on wires.He begins to notice that the people are paying more attention to the lion in the cage next to his.Not wanting to lose the attention of his audience，he climbs to the top of his cage，crawls across a partition(隔离物)，and dangles from the top to the lion's cage.Of course，this makes the lion very angry，but the crowd loves it.At the end of the day the zoo keeper comes and gives the mimic a raise for being such a good attraction.Well，this goes on for some time－the mimic keeps taunting the lion，the crowds grow larger，and his salary keeps going up.Then one terrible day when he is dangling over the angry lion he slips and falls.The mimic is terrified.The lion gathers itself and prepares to attack.The mimic is so scared that he begins to run round and round the cage with the lion close behind.Finally，the mimic starts screaming and yelling，“Help me，help me！”But the lion is quick and attacks.The mimic soon finds himself flat on his back looking up at the angry lion and the lion says，“Shut up，you idiot！Do you want to get us both fired？”

【小题1】The mimic visits the zoo to________.A．take care of the dying gorilla B．beg some money from the zoo keeper C．ask for a job there D．perform and earn some money there 【小题2】The zoo keeper offers the mimic a job to act as the gorilla because________.A．it is more expensive to hire a real gorilla B．the real gorilla died but the keeper does not want to lose its visitors C．he likes the mimic's performance D．he wants to help the mimic who is out of work 【小题3】What does the mimic feel about the new job at first? A．He likes it because he has enough freedom in the job.B．He likes it but he prefers to working as a mimic.C．He doesn't like it for people do not respect him.D．He doesn't like it because he gets little pay.【小题4】The mimic climbs to the lion's cage because________.A．he finds it more interesting to climb the cage B．he wants to play with the lion C．he wants to attract the attention of his audience D．he has never seen a lion before 【小题5】What does the passage mainly tell us? A．The mimic and his job B．The mimic and his success C．The actor and the mimic D．The mimic and his animals 【答案】

抱歉！您的用户级别不够，不能查看试题答案和解析。普通用户不能查看试题答案和解析。点击查看解决办法。题号：1775737，题型：阅读理解，难度：较易 标题/来源：2014届江西南昌三中高三8月第一次月考英语卷（带解析），日期：2013/11/1 【题文】I was reading these interesting stories behind a group of great logos in the world.Personally Nike is my favorite one – it’s so simple.And I liked the stories behind them, which made me forget all other things.McDonald’s, Apple, Mercedes Benz and Adidas own great logos as well, and they are among my favorites.Nike In the Greek myth, Nike is the goddess of victory and the source of inspiration for soldiers.This logo represents the wing in the famous statue of the Greek goddess.Nike’s logo was designed by Carolyn Davidson in 1971 for $ 35, and was registered as a trademark in 1995.McDonald’s

The logo was designed in 1962 by Jim Schindler to resemble the archshaped(拱形的)signs on the side of the company’s then walk-up hamburger stand.Later on, the two golden arches were combined together to form the M.The McDonald’s name was added to the logo in 1968.Apple There are different stories behind Apple’s logo.The first logo was a reference to the religious story of Adam and Eve, in which the apple represented the fruit of the Tree of Knowledge.One year later, the second logo was designed in 1977 by Steve Jobs and Ronald Wayne, and it described Sir Isaac Newton sitting under an apple tree.This logo didn’t stay long.One year later it was replaced almost immediately by graphic designer Rob Janoff’s “rainbow apple”, a rainbow-colored silhouette(轮廓)of an apple with a bite taken out of it.And then the rainbow-colored apple was replaced by the one-colored logo in 1998.It has not been changed so far.Mercedes Benz The Mercedes Benz logo, which was originally created by Gottlieb Daimler in 1909, consists of a simple description of a three-pointed star that represents its rule of the land, the sea and the air.The company was founded by Gottlieb Daimler and Wilhelm Maybach.Mercedes is the name of Maybach’s elder daughter, while Benz came as a result of a combination with Benz, Cie and DMG in 1926.Adidas The Adidas logo, which was created by the founder of the company Adi Dassler, represents mountains, pointing towards the challenges that are seen ahead and goals that can be achieved.The logo was used for the first time in 1967.【小题1】What does the author think of the stories of the great logos? A．They are attractive.B．They are practical C．They are boring.D．They are out of date 【小题2】What does Nike’s logo stand for? A．The statue of the Greek goddess.B．The wing of the Greek goddess.C．The goddess of victory.D．The source of inspiration for soldiers.【小题3】We can learn that Apple’s present logo is ______.A．Newton’s sitting under an apple tree B．the rainbow-colored bitten apple C．the religious story of Adam and Eve D．a bitten apple with only one color 【小题4】______ stands for the rule of the land, the sea and the air.A．The Mercedes logo B．The Adidas logo C．Nike’s logo D．Apple’s logo

【小题5】Which of the following time orders describes the births of the great logos? A．McDonald’s – Apple – Nike – Mercedes Benz.B．Nike– Mercedes Benz – McDonald’s – Apple.C．Mercedes Benz –McDonald’s – Nike – Apple.D．Nike– McDonald’s – Apple – Mercedes Benz.【答案】

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标题/来源：2014届江西吉水中学高三（实验班）上期10月英语卷（带解析），日期：2013/11/1 【题文】“Just take a deep breath.” “Don’t think about it.” “You’re more likely to die in a car wreck on the way to the airport than you are in a plane crash.” These are just some words given to people with a fear of flying.But as Tom Cruise, playing Lt.Daniel Kaffee in the movie A Few Good Men, said, “I get sick when I fly because I’m afraid of crashing into a large mountain.I don’t think Daniel will help.”

But there’s a new application that just may.Today, the VALK Foundation, a Dutch group that’s a partnership between KLM Royal Dutch Airlines and the University of Leiden, launches the app(application)in the US.The VALK Foundation was one of the first centers for research and fear-of-flying treatment in the world and is the organizer of three world conferences on fear of flying.The foundation said the app, called Flight App VALK, is the first scientifically-developed, web-based treatment for people who suffer from mild to moderate fear of flying.“The fear-of-flying application we have created aims to transfer all of the knowledge we have developed through our program into a mobile application that will help ease travelers’ fears,” said Dr.Lucas van Gerwen, director of the VALK Foundation.Dr.van Gerwen is also a psychologist and professional pilot with more than 30 years experience.The foundation said up to 30% of adults are fearful fliers.The Flight App is designed to help relax passengers before and during flights by educating users about flight safety and turbulence.It explains the sounds and sensations(感觉)they can expect during departure, flight and landing.And, if a passenger’s flight stress reaches a panic level, they press a special panic button which provides audio and written information to help decrease stress levels.Most importantly, the Flight App can be used during the flight in the airplane mode.Once downloaded, the program does not require Internet connection in the air.【小题1】By saying the words at the beginning of the passage, people are expected to ______.A．decrease their fear of flying B．get rid of their doubt about plane C．have a good time on their flight journey D．use some medicine to cure their fear of flying 【小题2】According to the passage, the VALK Foundation ______.A．is a group focusing on psychology on the flight B．was the first center to do research into fear of flying C．organizes the world conferences on fear of flying annually D．focuses on researching and offering treatment on fear of flying 【小题3】Flight App VALK is aimed to ______.A．help passengers experience the fear of flying B．help relax passengers before and during flights C．treat people who suffer from mild fear of flying D．teach people the basic knowledge of taking flight 【小题4】What does the last paragraph mainly tell us? A．Many adults are suffering from fear of flying B．It’s convenient for people to use the Flight App C．Many planes will be installed with the Flight App.D．The Flight App can decrease stress levels effectively 【小题5】In which column of a newspaper can we read this passage? A．Culture B．Entertainment C．Technology 【答案】

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D．Education