高中英语 Unit 3《Science versus nature》Welcome to the unit教案4 译林版必修5VIP免费

Unit3ScienceversusnaturePeriodoneWelcometothisUnitTeachingAims:Enablethestudentstoknowsomethingaboutcloning,andgivetheirownopinionsaboutcloning.Helpthestudentslearnhowtodescribetheadvantagesanddisadvantagesofhumancloningwiththetargetlanguage.Teachingimportantanddifficultpoints:Talkaboutcloningandhumancloning.Howtodescribetheadvantagesanddisadvantagesofhumancloning.TeachingProceduresStep1.Lead-inInthelastunit,welearnedsomethingabouttheenvironment.Nowourearthisfacedwithalotofproblems.Q1:whataretheproblems?(复习一下第二单元所学的知识，为下文做铺垫)Waterpollution,airpollution,rubbish,deforestation,desertification,andsandstormQ2:Let’shaveacompetition.Pleasethinkthatwhatweshoulddotoprotectourenvironment.Themorethebetter.Onemeasureisworth10points.(通过竞赛的形式激发学生的兴趣。为了使在这一轮竞赛中失利的同学继续保持信心，这轮比赛的分数要累计到下一轮竞赛中。)Fromthesemeasures,weknowthatprotectingtheenvironmentiseveryone’searth,includingplants,animals,humanbeings.But,somerareanimalsaredyingout,suchasrhinoceros,northeasttiger,white-flagdolphinandgiantpanda.Q3:whatshouldwedotoprotectthem?buildnaturereservemakelawstoprohibitthemfrombeinghuntedcloningInrecentyears,scienceisdevelopingsofastthatitisbeyondourimagination.Cloningisoneofthemoreadvancedtechnologies.（通过设计一系列的问题来导入到本单元的主题“克隆技术”）Step2Describingpictures.Today,wearegoingtolearnsomeinformationaboutcloning,nowlet’senjoysomepictures.Picture1Q1:Areyoufamiliarwiththesepictures?Q2:WhatdoyouknowaboutDolly?Theworld’sfirstclonedmammal.Q3:Whocreatedit?Scottishscientists.Q4:Whenwasitcreated?On22ndFebruary1996专心爱心用心1Q5:Isshestillalive?No,shediedin2003becauseoflungdisease.（设计这些问题是为了引起学生的兴趣，把这些知识都设计成问题形式是为了下文的一个竞赛做铺垫，加深学生对这些知识的印象）Dollywasworldfamousbecauseshewasexactlythesameashermother,inappearanceandingenes.Nowlet’slookattheprocessofherbirth.First,weneedthreefemalesheepandtakeakindofcellfromthefirstsheep,thentakeoutthecenterofthecell.Andthentakeanotherkindofcellfromthesecondsheep,andalsotakeoutthecenterofthecell,andthenputthecenterofthecelltakenfromthefirstsheepintothiskindofcell.Andputthisnewcellintothethirdsheep,andthentheclonedsheepDollywasborn.Doyouunderstand?（通过看一个Flash来描述克隆羊Dolly的克隆过程，使的学生更加了解克隆技术以及克隆过程，这样印象深刻，便于学生理解记忆）Picture2BesidesDolly,therearealotofanimalscloned.Forexample,Q1:What’sthis?It’samule,butitisn’tacommonmule,itistheworld’sfirstclonedmule.ItsnameisIdahoGem.Itwasbornon4May2003inAmerica.Ithasabrother,Taz,wasaracingmulethathaswonmanycompetitions.Q2:Doyouknowwhichonerunsfaster,theclonedmuleorthenormalone?Canyouguess?（设计这个问题是让学生进一步了解克隆动物的知识）Somescientistsarealsocuriousabouttheresult,sointhe20thsessionofWinnemuccamulecompetitionwhichwasheldinAmericaNevada,theyfoundthattwoclonedmulesbotharethefirstintheprimarycompetition,butinthefinals,theyonlyachievethethirdandseventh.Picture3Thecatisverybeautifulandlovely,doyouthinkso?Q1:What’sthenameofthiscat?CcQ2:whereisitsnamefrom?Itsnameisfrom“copycat”ScientistintheUSAcreateditwithacelltakenfromitsmotherRainbow.ItwasborninDecember2002.Picture4Therearefivelittlepigs.Theyarealsotheclonedanimals.TheirnamesareNoel,Angel,Star,JoyandMary.Theyareallfemale.TheywerebornonChristmasDay2001.TheyarefromScotland.Picture5Thep...