教案是教师授课的一种辅助工具,通过事前对学生的基础进行了解和把握,然后编制教案,通过课堂的授课讲述,让学生打下牢固的理论基础。以下是小编精心整理的《核酸教案高职范文》，供大家参考借鉴，希望可以帮助到有需要的朋友。
第一篇：核酸教案高职范文
核酸教案
第3节遗传信息的携带者——核酸
一、教材分析
《遗传信息的携带者——核酸》这一节虽然提出了遗传信息，但是对遗传信息的深入理解需要在必修2《遗传与进化》的模块中完成。本节课重点是让学生了解承载遗传信息的物质——核酸。通过上一节课所做的实验“观察DNA和RNA在细胞中的分布”，学生已经感受到遗传物质——核酸的真实存在和分布情况，这样对核酸有一个比较直观的感性认识，从而更好地理解核酸的种类有两种：脱氧核糖核酸(简称DNA)和核糖核酸(简称RNA)。在此基础上，理解核酸是一种生物大分子，它是由核苷酸连接而成的长链。教师可以从学生已有的学习知识入手，从核酸的基本组成元素出发，由元素组成核苷酸，由核苷酸组成核苷酸链，再形成核酸。注意利用课文中两种核苷酸的比较，以区分DNA和RNA的基本组成单位的不同，组成两种核苷酸碱基的不同和所含的五碳糖不同，提高归纳判断能力。
二、教学目标 1.知识目标
(1)说出核酸的种类。
(2)简述核酸的分子结构和功能。
(3)说出DNA和RNA在细胞中的分布情况。 2.能力目标
(1)尝试进行自主学习和合作学习。
(2)学会运用比较、归纳等方法分析实验结果。 3.情感态度与价值观
(1)参与小组合作与交流，培养学生自主、探究、合作式的学习方式。
(2)认识生物科学的价值，乐于学习生物科学，养成质疑、求实、创新及勇于实践的科学精神和科学态度。
(3)通过对核酸结构和功能的学习，使学生形成生物体内遗传信息多样化的观点。
三、教学重点和难点
重点：核酸的结构和功能。
难点：区别DNA和RNA各自的结构特点。
四、教学用具
多媒体教学课件、板书、动画。
五、教学过程 教学流程
教师活动
学生活动
设计意图
一、创设情境，导入新课。
以“华山游客要求退票被捅”事件为题，让学生试想一下，假如自己是警察，该如何破案?学生各抒己见。(提示：回忆破案片中警察会在犯罪现场收集什么?) 针对这个案子，警方将进行DNA鉴定以核实嫌疑人身份。 讲解：DNA指纹法技术在侦破工作中有着重要的用途。刑侦人员将从案发现场得到的血液、头发等样品中提取的DNA，与犯罪嫌疑人的DNA进行比较，就有可能为案件的侦破提供证据。
学生思考以下问题：
1.DNA指纹是不是平时说的手指印?
2.怎么知道那些DNA是否来自同一个人?(根据复杂的检测，观察DNA谱带是否完全相同)出示一张DNA指纹图，让学生推测谁是罪犯。 讲解：每个人的DNA都不相同，因此可以根据DNA提供犯罪嫌疑人的信息，而每个人的DNA之所以不相同，是因为它携带生物个体的遗传信息不同。
根据学生的个人情况作答。 认真听课，并做思考。
1、不是。
2、检测犯罪现场采集的DNA样品是否跟嫌疑犯的一样。 1号
以近期一个热点新闻话题为开篇，引起学生的注意，为DNA鉴定的引入做好铺垫。
学生对DNA指纹法在案件侦破中的作用可能略有所闻，让学生分组进行合作式的讨论，然后让学生进行交流表达、回答提出的疑问，尽可能地让所有学生分享他们对遗传物质——核酸的认识。
二、核酸的分类、功能
板书：
一、核酸的种类和功能
提问：生物体内的核酸有哪些种类?具有什么功能? 总结学生的回答，并适当写出板书。
学生已经预习过教材内容，可以回答出：核酸包括两大类：一类是脱氧核糖核酸，简称DNA;一类是核糖核酸，简称RNA。核酸是细胞内携带遗传信息的物质，在生物体的遗传、变异和蛋白质的生物合成中有重要的作用。
以问题的形式唤起学生对原有知识的记忆，且引起学生注意。
三、核酸在细胞中的分布
回忆上节课所做的实验：观察DNA和RNA在细胞中的分布。(板书：
二、核酸在细胞中的分布)
提问：实验用的染色剂是什么染色剂?它们各自可以让什么着色?DNA主要分布在细胞的什么部位?RNA呢?我们观察的是人口腔上皮细胞，它属于真核生物。那么原核生物中，DNA存在于什么部位呢?
吡罗红甲基绿混合染色剂;甲基绿使DNA呈现绿色，吡罗红使RNA呈现红色;DNA主要在细胞核，线粒体、叶绿体含少量。RNA主要在细胞质。 拟核中。
学生刚做完“核酸在细胞中的分布”这个实验，印象较深刻，以一连串问题带着学生一起回忆，使学生对DNA和RNA的分布印象更深刻。
四、认识核酸的结构
学生带着三个主要问题阅读课本P28～P29，进行自主学习和交流：
1、核酸的基本组成单位是什么?由那些分子组成?
2、基本组成元素有哪些?
3、DNA与RNA的区别?(化学组成、结构)
投影图片：课本P28，图2-8脱氧核苷酸和核糖核苷酸，课本P29，图2-10 DNA与RNA在化学组成上的区别，图2-9脱氧核苷酸长链，由学生对上述问题一一回答，老师对学生理解不到的地方作必要的补充说明。
出示一小段脱氧核苷酸链及一小段核糖核苷酸链，讲解：绝大多数生物体的细胞中，DNA由2条核苷酸链构成。RNA由1条核苷酸链构成。 强调核苷酸之间的连接位置。
学生快速阅读课本，回答问题：1.核苷酸是核酸的基本组成单位。一个核苷酸都是由一分子含氮的碱基、一分子五碳糖和一分子磷酸组成。 由C、H、O、N、P五种元素组成。
学生根据看书情况从五碳糖、含N碱基、核苷酸链的区别等方面回答。
培养学生自学、归纳能力。
引导学生观察与思考，主动活得知识。
通过PPT使抽象的语言变为直观的图解，帮助学生直观认识核苷酸。
五、小结、习题巩固
列出表格：DNA、RNA的主要区别，分别从全称、基本单位、五碳糖、含N碱基、结构、存在部分、显色反应几方面对比。
提问：为什么DNA(或RNA)分子有多样性? 总结出遗传信息蕴藏在核苷酸的排列顺序中。
提问：所有生物的遗传物质都是DNA吗?(RNA病毒的遗传物质是RNA)
布置学生下去查阅资料，思考：DNA鉴定技术除了可以用于破案，还能用在什么方面? 习题巩固。
根据刚才所学，完成表格。
学生从蛋白质的多样性得到启发，回答出脱氧核苷酸数量大，其排列顺序极其多样化。 延伸学习，引起思考。
使学生对DNA和RNA的区别掌握得更透彻。明确核酸分子的结构使之具有携带大量遗传信息的功能。
板书设计
第3节遗传信息的携带者——核酸 核酸的种类和功能
种类
DNA：脱氧核糖核酸
RNA：核糖核酸 功能：
二、核酸在细胞中的分布
DNA：真核细胞主要分布在细胞核内，原核细胞主要分布在拟核中。 RNA：主要分布在细胞质中。 核酸的分子结构
组成元素：C、H、O、N、P 含氮碱基
基本单位：核苷酸磷酸 五碳糖
脱氧核苷酸核糖核苷酸
磷酸、脱氧核糖、含N碱基磷酸、核糖、含N碱基 (A、T、C、G)(A、U、C、G) 核苷酸链：一般2条一般1条。
核酸：
DNA
RNA
第二篇：实验二 植物核酸的提取-教案
授课教师 学生人数 55 课 题 实验二 植物基因组DNA的提取 授课类型 新授课 授课方法 讲授、演示 教学目的 掌握CTAB法提取植物基因组DNA的原理与方法 教学重点 理解每一步实验操作的目的 教学难点 实验操作过程中的一些注意事项 教学过程
一、 背景知识
1.DNA在细胞中存在的位臵?植物细胞DNA存在的位臵和动物细胞有何不同?(图) 教学用具 多媒体
2.DNA的存在形式
双螺旋结构图
双螺旋结构组成
染色体是怎样形成的?
一级结构(核小体=双螺旋+组蛋白)-二级结构(螺线管)-三级结构(超螺线管)-四级结构(染色体)
真核生物基因组DNA是经过四级包装形成了染色体，先是DNA形成双螺旋结构，再与组蛋白形成核小体(一级结构)，压缩7倍，再形成螺旋管(二级结构)，压缩6倍，之后再形成超螺旋管(三级结构)，压缩40倍，最后超螺旋管压缩形成染色体(四级结构)，再压缩5倍，正常细胞中基因组DNA是以染色质(相当于一级结构)形式存在，在细胞分裂的中期以染色体形式存在，真核生物细胞质DNA主要是以裸露的环状DNA形式存在，没有核小体结构。
3.遗传物质核酸除了DNA外还有另外一种，即RNA，它与DNA在结构上的区别?(图)
RNA基本单位中间的五碳糖是核糖，含氮碱基尿嘧啶(U)替代 胸腺嘧啶(T) 4.核酸的理化性质
(1)形状：DNA为白色类似石棉样的纤维状物， RNA的纯品呈白色粉末或结晶。
(2)溶解性：一般都溶于水，不溶于乙醇、异丙醇、氯仿等有机溶剂，它们的钠盐比游离酸易溶于水。 (3)保存：在酸性溶液中，核酸易水解，中性或弱碱性溶液中较稳定。
二、实验目的
1.掌握CTAB法提取植物基因组DNA的原理 2.CTAB法提取植物基因组DNA的实验方法
三、实验原理
1.核酸在细胞中的存在方式，
是以核酸-蛋白质复合物的形式存在，如一级结构核小体(图)：DNA螺旋+组蛋白
2.通过低温研钵破坏植物细胞壁
3.加入CTAB溶解细胞膜，CTAB与核酸形成核酸-CTAB复合物，使核酸与蛋白质分离。
4.加入高盐溶液溶解核酸-CTAB复合物，加入蛋白质变性剂使蛋白质变性沉淀出来，离心除去蛋白质。 5.加入核酸沉淀剂，溶解CTAB，并使和核酸沉淀出来，离心得到核酸沉淀。
四、实验仪器 1.水浴锅
2.离心机(12管)：3台 3.研钵：10个
4.移液枪(包括枪头)：1ml、400ul
五、实验材料与药品
实验材料：新鲜菠菜叶片 1.十六烷基三甲基溴化铵(CTAB)
作用：溶解细胞膜并与核酸结合，便于分离核酸。 商品信息：瓶装/100g。
理化性质：白色或浅黄色结晶体至粉末状，有刺激气味，易溶于异丙醇，可溶于水,震荡时产生大量泡沫，化学稳定性好，耐热、耐光、耐压、耐强酸强碱。有吸湿性，在酸性溶液中稳定;溶于10份水，溶于热水、乙醇、三氯甲烷,易溶于异丙醇水溶液,微溶于丙酮,不溶于乙醚和苯。
储存：在阴凉，干燥，通风良好的地方，远离不相容的物质。 危害：高毒，对皮肤及粘膜刺激性小，有轻微脱脂作用。 2.1M Tris-HCl PH8.0缓冲液
作用：提供一个缓冲环境，防止核酸被破坏 商品信息：瓶/100ml，无色、澄清溶液
理化性质：Tris中文品名为三羟甲基氨基甲烷，瓶/500g。是一种白色结晶或粉末。溶于乙醇和水，微溶于乙酸乙酯、苯，不溶于乙醚、四氯化碳，对铜、铝有腐蚀作用，有刺激性的化学物质。
储存：室温保存。
危害：毒性低，可致癌，不要直接接触皮肤。 3.乙二胺四乙酸二钠(EDTA-2Na)
作用：螯合Mg2+或Mn2+离子,抑制脱氧核糖核酸酶(DNase)活性，活性依赖于钙离子，并能被镁离子或二价锰离子激活。
商品信息：瓶/250g。
理化性质：无味无臭或微咸的白色或乳白色结晶或颗粒状粉末。溶于水，不溶于乙醇、乙醚，其水溶液pH值约为5.3。可由EDTA与氢氧化钠和碳酸钙作用制得。
储存：于阴凉、通风的库房。远离火种、热源。应与氧化剂分开存放，切忌混储。配备相应品种和数量的消防器材。储区应备有合适的材料收容泄漏物。
危害：对粘膜和上呼吸道有刺激作用。对眼睛、皮肤有刺激作用。本品可燃，具刺激性。 4.Tris饱和酚
作用：强蛋白质变性剂。 商品信息：瓶/250ml。
理化性质：为浅黄色透明液体，上层为Tris-HCl溶液，加有抗氧化的0.25% 8-羟基喹啉和0.1%的β-巯基乙醇。
储存：4℃避光保存。
危害：Tris饱和酚有较强的腐蚀性，应尽量避免皮肤直接接触或吸入体内。如发现变为黄色或棕色，表明发生氧化，不能使用。 5.β-巯基乙醇(2-巯基乙醇)
作用：提供一种还原剂，这样酚类物质(植物材料特别是老的材料中含有大量的酚类物质)就不能被氧化成醌(醌易与DNA发生共价结合，使DNA发生褐变，从而影响你提DNA的实验)。巯基乙醇兼有消除CTAB震荡时产生的泡沫的作用。
商品信息：瓶/100g。
理化性质：无色透明液体，具有少许硫醇气味。易溶于水，乙醇和乙醚等有机溶剂，与苯可以任意比例混溶。水中溶解度：1mg/mL。
储存：对空气敏感，易吸潮。 使容器保持密闭，储存在阴凉、干燥通风处。打开了的容器必须仔细重新封口并保持竖放位臵以防止泄漏。建议贮存温度 2- 8℃。
危害：高毒吸入 、摄入或经皮肤吸收后会中毒。 对环境有危害，对水体可造成污染。 本品可燃。 6.氯化钠(NaCl)
作用：CTAB-核酸复合物在高盐溶液中易溶。 商品信息：瓶/500g，分析纯AR。
理化性质：白色晶体状。易溶于水、甘油，微溶于乙醇、液氨;不溶于浓盐酸。在空气中微有潮解性。稳定性比较好。
储存：储存于阴凉、通风的库房。远离火种、热源。应与氧化剂分开存放，切忌混储。 危害： 7.无水乙醇
作用：DNA沉淀剂、洗涤剂。 商品信息：瓶/500ml，分析纯AR。
理化性质：无色澄清液体。极易从空气中吸收水分，能与水和氯仿、乙醚等多种有机溶剂以任意比例互溶。 储存：储存于阴凉、通风的库房。远离火种、热源。库温不宜超过30℃。保持容器密封。应与氧化剂、酸类、碱金属、胺类等分开存放，切忌混储。采用防爆型照明、通风设施。禁止使用易产生火花的机械设备和工具。
危害：易燃，具刺激性。蒸气与空气能形成爆炸性混合物，爆炸极限3.5%～18.0%(体积)。 8.氯仿(三氯甲烷)
作用：蛋白质变性剂，加速有机相与液相分层，去除核酸溶液中的少量酚(酚易溶于氯仿)。 商品信息：瓶/500ml。
理化性质：无色透明液体，极易挥发，有特殊气味。不溶于水，溶于醇、醚、苯。 储存：保存在密封的棕色瓶中。
危害：麻醉性。有致癌可能性。在光照下遇空气逐渐被氧化生成剧毒的光气。 9.异戊醇
作用：减少蛋白质变性操作过程中产生的气泡。异戊醇可以降低表面张力，从而减少气泡产生。另外，异戊醇有助于分相，使离心后的上层含DNA的水相、中间的变性蛋白相及下层有机溶剂相维持稳定。
商品信息：瓶/500ml。
理化性质：无色液体，有不愉快的气味。微溶于水，可混溶于醇、醚等有机溶剂。
储存：储存于阴凉、通风的库房。远离火种、热源。库温不宜超过30℃。保持容器密封。应与氧化剂、酸类等分开存放，切忌混储。采用防爆型照明、通风设施。禁止使用易产生火花的机械设备和工具。储区应备有泄漏应急处理设备和合适的收容材料。
危害：吸入、口服或经皮肤吸收有麻醉作用。其蒸气或雾对眼睛、皮肤、粘膜和呼吸道有刺激作用，可引起神经系统功能紊乱，长时间接触有麻醉作用。易燃，其蒸气与空气可形成爆炸性混合物，遇明火、高热能引起燃烧爆炸。 10.异丙醇
作用：DNA沉淀剂，DNA在异丙醇的溶解度更低，所以用异丙醇来沉淀更完全，而后由于异丙醇不易挥发，所以用乙醇洗去异丙醇，乙醇挥发快。用-20度预冷异丙醇沉淀效果较等体积乙醇沉淀好;异丙醇约和2.5倍体积的乙醇效果相当;但DNA微溶于乙醇，使用乙醇沉淀会使部分DNA溶解损失;所以多选用-20度预冷异丙醇。一般6500倍到8000倍重力10分钟就可以将异丙醇沉淀的核酸紧密的离到管底。
商品信息：棕色玻璃瓶/500ml。
理化性质：无色透明具有乙醇气味的可燃性液体。有似乙醇和丙酮混合物的气味，能与醇、醚、氯仿和水混溶，不溶于盐溶液。
储存：储存于阴凉、通风的库房。远离火种、热源。库温不宜超过30℃。保持容器密封。应与氧化剂、酸类、卤素等分开存放，切忌混储。采用防爆型照明、通风设施。禁止使用易产生火花的机械设备和工具。储区应备有泄漏应急处理设备和合适的收容材料。
危害：微毒类，高浓度蒸气具有明显麻醉作用，对眼、呼吸道的黏膜有刺激作用，能损伤视网膜及视神经。常温下可引火燃烧，其蒸汽与空气混合易形成爆炸混合物。 11.PVP-40(聚乙烯吡咯烷酮)
作用：PVP是酚的络合物，能与多酚形成一种不溶的络合物质，有效去除多酚，减少DNA中酚的污染;同时它也能和多糖结合，有效去除多糖。
商品信息：白色塑料瓶/100g。
理化性质：白色或乳白色粉末或颗粒，有微臭。溶于水、碱、酸及极性有机溶剂。 储存：室温干燥保存。 危害： 12.液氮(LN2)
作用：低温导致植物组织冻裂，方便研磨使细胞破碎，使DNA释放完全;低温情况下各酶处于低活性状态，有利于抑制DNAase的作用，保护DNA。 商品信息：分析纯
理化性质：-196℃。液态的氮气。是惰性的，无色，无臭，无腐蚀性，不可燃，温度极低。 储存：储存于阴凉、通风的库房。库温不宜超过30℃。 危害：汽化时大量吸热接触造成冻伤。
六、实验试剂
1.氯仿-异戊醇(24:1)100ml-20ml=80ml {氯仿 96ml + 异戊醇 4ml} = 100ml，4℃保存 2.酚-氯仿-异戊醇(25:24:1)40ml {氯仿-异戊醇(24:1)20ml + Tris饱和酚20ml} = 40ml，4℃保存 3.TE缓冲液 PH8.0 50ml {10mM Tris-HCl(PH8.0)缓冲液 0.5ml + 0.5M EDTA(PH8.0)0.1ml} → → 定容到50ml → 高压灭菌后冷却4℃保存 【0.5M EDTA(PH8.0)】的配制：100ml {蒸馏水 80ml + EDTA-2Na.2H2O 18.61g} → 用NaOH(约2g)调至PH8.0 → 定容至100ml → → 分装后高压灭菌备用。注：需加入NaOH调至PH8.0才能完全溶解。 【10mM Tris-HCl(PH8.0)缓冲液】的配制：10ml {1M Tris-HCl PH8.0缓冲液100μl + 水9.9ml} → 定容至10ml → 10mM Tris-HCl(PH8.0)缓冲液 4. 2%CTAB抽提液 250ml
{CTAB 4g + 无水乙醇 5ml + 水100ml} → 加入200ml烧杯中 → 加热溶解 → 再依次加入 → → {5M NaCl 56ml + 1M Tris-HCl(PH8.0)20ml + 0.5M EDTA 8ml} → 定容至250ml → 高压灭菌冷却后加入 → {1%β-巯基乙醇(400ul)2ml + PVP-40 5g} → 4℃保存 【5M NaCl溶液】配制：100ml {NaCl 29.22g + 水90ml} → 加热到80℃溶解冷却后 → 定容至100ml → 高压灭菌备用 【1%(v/v)β-巯基乙醇】配制：10ml {β-巯基乙醇 100μl +水9.9ml} → 1%β-巯基乙醇10ml 5.蒸馏水
所有药剂用水都要纯净水经高压灭菌冷却
七、实验步骤
(一)实验前准备
1.研钵、异丙醇-20℃预冷;【研钵10个、异丙醇75ml】
2.将2%CTAB抽提液从4℃冰箱内取出在65℃水浴预热;【CTAB抽提液30ml】 3.称取30份新鲜菠菜叶片，每份1g，称重时去叶脉;【菠菜叶片30g】 4.用蒸馏水冲洗叶片，滤纸吸干水分，将叶片用剪刀剪小。【洗瓶、滤纸、剪刀】
5.实验器材：冰箱、65℃水浴锅、液氮、10ml离心管90个、药匙、移液枪(1ml、100μl、400μl)、离心机(10000r/min)
6.实验药剂：酚-氯仿-异戊醇30ml(每管1ml)、氯仿-异戊醇60ml(每管2ml)、无水乙醇12ml(每管400 μl)、TE缓冲液3ml(每管100μl)
(二)破碎细胞，释放溶解核酸
1.将叶片臵于预冷的研钵(实验前-20℃预冷)中，倒入液氮，尽快研磨成粉末;
目的：低温导致植物组织冻裂，方便研磨使细胞破碎，使DNA释放完全;低温情况下各酶处于低活性状态，有利于抑制DNase的作用，保护DNA。
2.将粉末加入10ml离心管中，加入 1ml预热的CTAB 抽提缓冲液，轻轻搅动摇匀; 目的：CTAB可以溶解细胞膜并与DNA结合，便于分离DNA。加入β-巯基乙醇和PVP-40的目的是减少植物中酚类物质的影响。EDTA的作用是螯合Mg2+或Mn2+离子,抑制脱氧核糖核酸酶(DNase)活性，活性依赖于钙离子，并能被镁离子或二价锰离子激活。Tris-HCl提供一个缓冲环境，防止DNA被破坏。高盐溶液可以更好的溶解核酸-CTAB复合物。
3.将离心管臵于 65℃的水浴中保温40分钟，期间每隔10分钟轻轻摇晃几次。 目的：水浴使CTAB抽提液和叶片充分反应。
(三)抽提去掉蛋白质
1.将水浴的离心管取出，冷却 2分钟后，加入1ml酚-氯仿-异戊醇，振荡 2分钟，使两者混合均匀，12000 r/min离心10分钟; 目的：第一次离心溶液分3层，上-中-下层：CTAB-核酸-变性蛋白-有机溶剂
2.取上清液(含CTAB-核酸)至新的10 ml离心管中，加入2ml氯仿-异戊醇，轻轻颠倒离心管，混匀，12 000r/min离心10分钟。 目的：第二次离心进一步去掉变性蛋白，去掉多余的酚
(四)沉淀核酸
1.小心取上清液(含CTAB-核酸)臵于一个新的10ml离心管中(尽量避免吸取中间层),加入2.5ml的异丙醇(-20℃预冷)，将离心管慢慢上下摇动30秒，使异丙醇与水层充分混合，室温放臵15分钟至能见到DNA絮状物; 目的：异丙醇为DNA沉淀剂，异丙醇与CTAB互溶，但不与核酸相溶。用-20℃预冷的异丙醇沉淀效果较等体积乙醇沉淀好，异丙醇约和2.5倍体积的乙醇效果相当，但核酸微溶于乙醇，使用乙醇沉淀会使部分核酸溶解损失;所以多选用-20度预冷异丙醇。核酸在异丙醇的溶解度更低，所以用异丙醇来沉淀更完全。异丙醇易溶于CTAB，但不与核酸相溶。 2.10000r/min离心10分钟,小心倒去上清液。 目的：第三次离心使核酸沉淀到管底。
(五)核酸的洗涤
用400ul无水乙醇洗涤核酸沉淀直至无色，10000r/min离心10分钟，倾去上清液晾干。 目的：异丙醇不易挥发，所以用乙醇洗去异丙醇及多余的NaCl，乙醇挥发快。
(六)保存
向下层离心物中加入100μl TE缓冲液进行溶解，臵于-20℃冰箱保存，以便下次课用。 目的：一般长期保存DNA，贮存在TE缓冲液中比较好。TE为含EDTA的Tris-HCl(PH 8.0)缓冲液：其中比较关键的成分是EDTA，日常环境中不可避免的存在DNase，而DNase的活性依赖于钙离子，并能被镁离子或二价锰离子激活。镁离子存在条件下，DNase I可随机剪切双链DNA的任意位点;二价锰离子存在条件下，DNase I可在同一位点剪切DNA双链，形成平末端，或1-2个核苷酸突出的粘末端。TE中含有的EDTA可以螯合金属离子，从而使DNase失活。而Tris-HCl的作用主要是维持一定碱性PH值，有助于DNA的溶解和稳定。不加EDTA也是可以的，而且EDTA会影响下游酶切，连接反应以及质粒转染进细胞的效率，如果接下来要做这些实验是应该避免使用含EDTA的缓冲液的。短期储存DNA也可以使用ddH2O，有助于DNA连接等效果。
八、实验注意事项
1.在整个实验过程中应严格执行无菌操作; 2.部分药品有毒，操作中应注意安全防护;
3.磨样时最好是加液氮，磨样速度要快，使材料处于低温状态; 4.刚投入水浴时可以稍快速的晃动，之后的晃动一定要轻柔; 5.抽提时不要有太力振动，操作也要仔细，尽量避免DNA断裂;
6.将异丙醇吸出时用的枪头一定要剪过的，这点很重要，过尖的枪头会把DNA链弄断。
九、思考题
1.本实验中用到的各种试剂的作用是什么? 2.本实验中进行了几次离心操作，每次的目的?
十、实验安排
全班55人，按照学号分组，每6人一组，共9组，最后一组7人。 每组作3个离心管，共用一个研钵。
每3组(共18人9个离心管)共同进行离心操作。
第三篇：3 遗传信息的携带者──核酸 教学设计 教案
教学准备
1. 教学目标
1.知识与技能
(1)说出核酸的种类。
(2)简述核酸的分子结构和功能。
(3)懂得以特定的染色剂染色，观察并区分DN A和RNA在细胞中的分布。 2.过程与方法
(1)尝试进行自主学习和合作学习。
(2)学会运用比较、归纳等方法分析实验结果。 (3)运用互联网、图书、杂志进行资料的收集和整理。
(4)积极参 加社区实践活动，并尝试进行调查报告的写作。3.情感态度与价值观 (1)参与小组合作与交流，培养学生自主、探究、合作式的学习方式。
(2)认识生物科学的价值，乐于学习生物科学，养成质疑、求实、创新及勇于实践的科学精神和科学态度。
3.情感态度方面：用实验的方法，观察DNA、RNA在细胞中的分布。
2. 教学重点/难点
教学重点
1.核酸的分子结构和功能。
2.观察并区分DNA和RNA在细胞中的分布。 教学难点
观察DNA和RNA在细胞中的分布。
3. 教学用具
多媒体
4. 标签 生物,人教版,教案
教学过程 [情境创设]
以下是一个真实的故事：检验荔枝DNA找到杀人者
一个年仅12岁的女孩，失踪数日后，在村边的臭水沟中被人发现尸体。侦查人员在死者胃里发现了一种呈咖啡色的肉丝状物质，随后又在嫌疑人家中发现了一些发霉的荔枝壳和荔枝核，两者之间究竟有无关联?
检验人员运用植物DNA检验技术，采用多对引物进行扩增检验，结果证明在死者胃内发现的咖啡色肉丝状物质就是荔枝肉。检验进一步证明，死者胃内所发现的荔枝肉和嫌疑人家中发现的荔枝壳具有同一来源的特性，在所有的引物扩增检验结果中，果肉和外壳都呈现出相同的DNA谱带。同时，警方从市场上随机购买的荔枝却与前两者的DNA谱带不同。
这个结果说明一个事实，在死者胃内发现的荔枝肉与在嫌疑人家中发现的荔枝壳是同一棵树上结的果实，具有同一性。在证据面前，嫌疑人供认了犯罪过程。 DNA指纹法技术在侦破工作中有着重要的用途。众所周知，每个人都有指纹，而且每个人的指纹都很独特，刑侦人员将从案发现场得到的血液、头发等样品中提取的DNA，与犯罪嫌疑人的DNA进行比较，就有可能为案件的侦破提供证据。那么什么是DNA指纹呢?DNA是什么?为什么DNA能够提供犯罪嫌疑人的信息? [师生互动]
(一)学生分小组进行合作式的讨论和交流
学生对DNA指纹法在案件侦破中的作用可能略有所闻，让学生分组进行合作式的讨论，然后让学生进行交流表达、回答提出的疑问，尽可能地让所有学生分享他们对遗传物质——核酸的认识。 1.DNA指纹是不是平时说的手指印?(不是)
2.怎么知道那些DNA是否来自同一个人?(根据复杂的检测，观察DNA谱带是否完全相同)
3.DNA可以做身份证吗?(可以。而且这种身份证是终身的，也是唯一的，能避免同名同姓同地点同时出生的人身份混淆) „„ 可以由学生自由提问，在老师组织下，由同学答疑，回答不上来的，再由老师作补充。
为什么DNA能够提供犯罪嫌疑人的信息，这与DNA是遗传物质的本质是分不开的，因此通过对DNA指纹的鉴定，可以判断两个人之间的亲缘关系，DNA指纹在人的一生中是无法改变的，因此，科学家只需要一滴血、一根头发等就可以对其DNA指纹进行鉴定。DNA指纹分析除了用于破案以外，还广泛用于其他很多方面，如亲子鉴定、鉴别移民、孤儿、难民、遇难者的身份等。 4.DNA的中文名称是什么呢?(脱氧核糖核酸) 5.脱氧核糖核酸属于哪一类的有机化合物?(核酸)
6.核酸有哪些种类?有什么功能?(核酸包括两大类：一类是脱氧核糖核酸，简称DNA;一类是核糖核酸，简称RNA。核酸是细胞内携带遗传信息的物质，在生物体的遗传、变异和蛋白质的生物合成中有重要的作用)
7.一个细胞的基本结构是什么?核酸存在于细胞的哪些部位?(细胞有细胞膜、细胞质、细胞核等几个部分，植物细胞还有细胞壁、液泡等特殊结构) 8.大家能否通过实验，判断DNA和RNA在细胞中的分布情况?
(二)老师介绍实验的原理以及科学认识的模式
原理：甲基绿和吡罗红两种染色剂对DNA和RNA的亲和力不同，甲基绿使DNA呈现绿色，吡罗红使RNA呈现红色。利用甲基绿和吡罗红混合染色剂将细胞染色，可以显示DNA和RNA在细胞中的分布。盐酸能够改变细胞膜的通透性，加速染色剂进入细胞，同时使染色体中的DNA与蛋白质分离，有利于DNA和染色剂结合。
科学认识模式是“假设检验”，即在提出问题后，接着提出猜测性的假设，然后用观察和实验来检验。这种科学认识模式的程序是问题→试探性假设→批判与检验。这是科学探究的一般程序，也是探究性学习的一般程序。
(三)找一个预习作业做得比较好的同学，陈述实验如何进行 A.问题的提出：DNA和RNA在细胞中是怎么分布的? B.试探性假设：DNA分布在细胞核，RNA分布在细胞质。
C.实验检验：甲基绿使DNA呈现绿色，吡罗红使RNA呈现红色，通过观察两种颜色出现的部位来判断DNA和RNA在细胞中的分布。 实验方法步骤 1.取口腔上皮细胞 (1)在洁净的载玻片上，滴一滴质量分数为0.9%的NaCl溶液。
(2)用消毒牙签在自己漱净的口腔内侧壁上轻轻地刮几下，把牙签上附有碎屑的一端，放在载玻片的液滴中涂抹几下。
(3)点燃酒精灯，将涂有口腔上皮细胞的载玻片烘干。 2.水解
(1)在小烧杯中加入30 mL质量分数为8%的盐酸，将烘干的载玻片放入小烧杯中。
(2)在大烧杯中加入30 ℃温水。
(3)将盛有盐酸和载玻片的小烧杯放在大烧杯中保温5 min。 3.冲洗涂片
用蒸馏水的缓水流冲洗载玻片10 s。 4.染色
(1)用吸水纸吸去载玻片上的水分。
(2)将吡罗红甲基绿染色剂滴2滴在载玻片上，染色5 min。 (3)吸去多余染色剂，盖上盖玻片。 5.观察
先用低倍镜找到染色均匀、色泽浅的区域，再用高倍镜观察各部分的染色情况。
(四)教师把实验关键的步骤作多媒体演示
请你把观察到的实验现象记录在下表中，分析得出结论。
(五)各实验小组的学生交流实验结果
请你和其他实验小组交流实验现象和结论，你们得出的结论是一样的吗? 结论：通过各种动植物实验材料的观察，同学们观察到的结果非常相似，在细胞核部分被染成了绿色，而在细胞质部分被染成了红色。说明DNA主要分布在细胞核中，RNA主要分布在细胞质中。
(六)学生带着三个主要问题阅读课本P28～P29，进行自主学习和交流 1.核酸的组成元素有哪些? 2.核酸的分子结构是怎么样的? 3.如何区分DNA和RNA?
老师投影图片：课本P28，图2-8脱氧核苷酸和核糖核苷酸、图2-9脱氧核苷酸长链，课本P29，图2-10 DNA与RNA在化学组成上的区别，由学生对上述问题一一回答，老师对学生理解不到的地方作必要的补充说明。
核酸由C、H、O、N、P五种元素组成。核酸水解后得到很多核苷酸。核苷酸是核酸的基本组成单位。
观察图2-8脱氧核苷酸和核糖核苷酸，比较脱氧核苷酸和核糖核苷酸分子结构有什么异同?(观察能力的培养)
相同点：一个核苷酸都是由一分子含氮的碱基、一分子五碳糖和一分子磷酸组成。很快也能观察到组成两者的糖不一样，组成脱氧核苷酸的糖比核糖核苷酸的糖少了一个氧原子。
观察脱氧核苷酸长链图。此图是一小段脱氧核苷酸长链，图中有多少个脱氧核苷酸分子?(5个)每个核酸是由几十个乃至上亿个核苷酸连接而成的。绝大多数生物体的细胞中，DNA由2条核苷酸链构成。RNA由1条核苷酸链构成。
课堂小结
本节课，充分发挥教材中蕴含的创新、探究的素材，通过多处“设障”、“布惑”，将教材进行活化和优化处理，使之真正成为学生的“学材”，潜移默化地把培养了学生的对实验结果分析、数据分析、解决实际问题能力。
本节课利用了一课时完成，时间有些紧张比。关键的因素在于学生实验的熟练程度和对有机化学知识的陌生，由此直接导致实验耗时多或没有得到准确的结果，看DNA的结构式不明就里，从而影响了教学效果。因此，对于学生的实验能力和有机化学知识可有适当补充。以“探究—发现”教学模式贯穿教学，从课堂的学生表现来看，学习主动性得到了较大程度调动，课堂始终处在一种主动学习的良好氛围之中，学生真正把学习的过程演绎成一个主动探究、自动求知的过程。
课后习题
1.水稻叶肉细胞中的DNA主要存在于
(
)
A、细胞质
B、细胞核
C、线粒体 D、叶绿体
答案：B 2.下列哪一组物质是DNA的组成成分
)
A.脱氧核糖、核酸和磷酸
B.脱氧核糖、碱基和磷酸 C.核糖、碱基和磷酸
D.核苷、碱基和磷酸
答案：B 3.组成核酸的碱基、五碳糖、核苷酸各有多少种
(
) A.
5、
2、8
B.
4、
2、2
C.
5、
2、2
4、8
答案：A 4.所有的核苷酸分子中都含有
(
)
A.核糖
B.含氮碱基
C.脱氧核糖
D.氨基酸
答案：B 5.细胞内的遗传物质是
A、DNA
B、RNA
C、DNA或RNA
D、DNA和RNA 答案：A 6.杨树叶肉细胞中的核酸，含有的碱基种类是
(
)
( 、
D. 4 A、1种
B、8种
C、4种
D、5种
答案：D
板书
第3节
遗传信息的携带者——核酸
一、核酸的种类和功能 功能：
二、核酸在细胞中的分布 DNA：主要分布在细胞核内 RNA：主要分布在细胞质中
三、核酸的分子结构
第四篇：3_遗传信息的携带者──核酸_教学设计_教案
教学准备
1. 教学目标
【学习目标】: 1.说出核酸的种类，简述核酸的结构和功能
2. 以特定的染色剂染色，观察并区分DNA和RNA在细胞中的分布
3.能看懂脱氧核糖核苷酸和核糖核苷酸结构图解、DNA和RNA在化学组成上的区别图解，以及核苷酸长链的特点
2. 教学重点/难点
【学习重点】:核酸的结构和功能。
【学习难点】:观察DNA和RNA在细胞中的分布。
3. 教学用具 4. 标签
教学过程
【学习过程】
一、预习.自主整理:阅读课本，完成以下题目
一、核酸的种类和功能
核酸包括___________________(DNA)和__________________(RNA) 功能：核酸是细胞内____________的物质，在________________________具有极其重要的作用。
二、核酸在细胞中的分布
甲基绿使_____________呈现___________ ,吡罗红使_________呈现 ___________________
盐酸的作用
___________________________________________________________________
三、核酸的结构组成
核酸的基本组成单位是_________ 。一个核苷酸是由一分子___________ 、一分子________和一分子 _____________组成的。核苷酸根据 ____________的不同，分为 _________________和核糖核苷酸。
在大多数生物体的细胞中，DNA由___________条核苷酸链构成，RNA由_____条核苷酸链构成。 碱基的种类：
DNA：A _____________ G______________ C ____________ T __________________
RNA：A______________ G______________ C _____________ U _______________
二.课堂研讨
导入：如果你是一个投资者，你会将资金投入到核酸保健品的开发中吗?要做出这个决策，你肯定要做一番可行性研究，你会从哪些方面研究核酸呢?
(一)核酸的种类及功能
(二)核酸在细胞中的分布(观看实验)
思考：1判断DNA和RNA在细胞中分布的依据是什么?
2、盐酸在实验中的作用是什么?
3、DNA、RNA在真核细胞中是怎么分布的?原核细胞的DNA位于细胞的什么部位?
(三)核酸的结构
1.核酸、DNA、RNA的基本单位分别是什么?
2.核苷酸是由几分子构成?化学元素?
3.构成脱氧核苷酸、核糖核苷酸的五碳糖有什么不同?
课堂小结：
能力提升
绝大多数生物的遗传信息贮存在DNA分子中，四种脱氧核苷酸如何组成种类繁多的DNA分子的呢?
课后习题 【随堂练习】
1、
用于观察核酸在细胞中的分布的试剂是( ) A、斐林试剂
B、双缩脲试剂
C、苏丹Ⅲ染液
D、吡罗红、甲基绿混全染色剂
2、由一分子含氮碱基、一分子五碳糖和一分子磷酸所形成的化合物是( ) A、RNA
B、DNA
C、核酸
D、核苷酸
3、下列能够聚合形成DNA分子的物质是( ) A、 脱氧核糖
B、脱氧核苷酸
C、氨基酸
D、含氮碱基
4、在洋葱根尖细胞中，组成核酸的碱基，五碳糖，核苷酸各有多少种 A、
5、
2、8
B、
4、
2、2
C、
5、
2、
2、
D、
4、
4、8
5、图的各小图中，正确代表脱氧核苷酸的结构是(
)。
第五篇：高职高专听力教案1
Unit 1 Greeting People You Meet for the First Time
Teaching aims: 1) Students will be better able to improve their skill of prediction, listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
toothache
refer
customs
introduction
respect formal
discouraged
stranger
hurry
acquainted Phrases and Patterns: In some cases
in a great hurry
appear to be
lack of
first of all Get acquainted with
in common with
find out
lie in
instead of
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 1, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these converstions. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 3. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 3-Page 6 and compare the answers with the key on the back part of the book.
Unit 2 Introducing People to Each Other
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
realize
seldom
address
practiced
handshake occasions handshake
popular
argue
urge
Phrases and Patterns: argue with
take turns
feel relaxed
be respectful
sooner or later on such social occasions
a little late
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 7 to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 3) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 4) Ask learners to write down the content on page 9. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 9-Page 12 and compare the answers with the key on the back part of the book.
Unit 3 Getting and Giving Information About People
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
Thai
hostess
Singapore
diligently
contemporary Thrilled
Brazil
corporation
Italian
abroad Phrases and Patterns: make preparations
apply for
be afraid that
be left behind
as soon as sit down
take pictures
travel abroad
last minute trouble
first of all
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 13, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 15 Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 15-Page 19 and compare the answers with the key on the back part of the book.
Unit 4 Making a Telephone Call
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
dial switchboard extension check message available
offer
call Phrases and Patterns: put through
pick up
find out
take down
offer to put ab. through
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 21, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 22. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 23-Page 26 and compare the answers with the key on the back part of the book.
Unit 5 Can I See Your Magnager
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
electronic enjoy
interested
applicant
experience
appointement
Phrases and Patterns: look for
work as
enjoy oneself
make an appointment
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 27, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 29. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 29-Page 32 and compare the answers with the key on the back part of the book.
Unit 6 Greeting People You Meet for the First Time
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
block notice
respect
protect
attitude
disappointed
suggestion
entrance
remain polite Phrases and Patterns: whether...or
take off
from then on
care about
allow sb. to do care about
not...until
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 3) Ask students to describe the pictures on top of page 33, to activate their thinking and arouse their learning interest. 4) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 35. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 35-Page 38and compare the answers with the key on the back part of the book.
Unit 7 At the Information Desk of a Travel Agency
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
overseas
schedule
crafts
intend
pandas
professor
international
limited
president
particularly
Phrases and Patterns: In order to
start off
feel tired
arrange for
interested in Make a schedule for
see...performing
enjoy...particularly
arrange a reception for
leave for
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 47, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 49. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 49-Page 52 and compare the answers with the key on the back part of the book.
Unit 8 Flight Departures and Arrivals
Teaching aims: 1) Students will be better able to improve their skill of prediction,listening for main idea and specific information while listening to the recording in this unit. 2) Students will be better able to improve their spoken skill of fluency while discussing the exercises and describing pictures. 3) Students will be better able to improve their writing skill while describe picture in written form.
Teaching focus: New words:
nervous
seasick
hate
sleepy
ride
manage
high-heeled
comfortable
symposium
facility
Phrases and Patterns: by air
this field
make...feel
watch TV
make...fee in the different parts of the world
be interested in
Anticipated problems: It is possible that some of the exercises are too difficult for learners to find out answers within two times listening. In that case, the teacher replays the recording or reads the recording orally.
Teaching stages: Stage 1: warming-up 1) Ask students to describe the pictures on top of page 53, to activate their thinking and arouse their learning interest. 2) Ask Ss to discuss the following question: How will you greet people you meet for the first time in your language and in English? And why? It is a way to make some preparation for the next step. Stage 2 Prediction Ask learners to predict the content of these conversation. Stage 3 Reading Ask learners to look through the questions listed in Conversation part. Remind them of focusing their attention on specific information rather than all of the information while listening to the cassette. Stage 4 Listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 5 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 6 Reading and prediction Ask learner to predict the content of the passage after the looking through the questions. Stage 7 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 8 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 10Reading
Ask learner to read the questions quickly before they listen to the recording. Stage 11Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 12 Prediction Ask learners to predict the content of picture identification. Stage 13 listening Play the recording of the five conversations two times and ask learners to finish the exercises. Stage 14 Feedback 1) Ask learners to compare their answers with each other before we gonging over the answer. 2) Ask some learners to give the answers by reading both the questions and answers individually. Stage 15 Group work 1) Ask learners to describe the picture in the exercise of Picture description orally in small groups. 2) Ask learners to write down the content on page 55. Stage 16 Feedback Ask one reporter to the rest of the class a report orally.
Homework: Finish the exercises from Page 55-Page 58 and compare the answers with the key on the back part of the book.