Unit5Canada-＂TheTrueNorth＂全国优质课一等奖

TheheartBeforeyoureadWhatdoyouknowabouttheheart?Howdoesitwork?Canyouguesshowmanytimesaheartbeatsinanaveragelifetime?Theanswerisinthepassagebelow.Reading(1)TheheartTheheartisthesymbolofemotionssuchasgratitude,love,hatred,courageandfear.Peoplemaybedescribedasgiving"heartfelt"thanks,lovingwith"alltheirheart",havinga"blackheart",being"bravehearted"orbeing"fainthearted".Inreality,theheartisalife-givingpump,amusclethatisessentialforprovidingthebodywiththepowerthatitneedstofunction.Itcontinuestoworkceaselesslyuntildeath.Yourheartisasmallpump,aboutthesamesizeasyourfist.Itismadeupoffourchambers:thetwoatthetoparecalledtheatria,whilethetwoonthebottomaretheventricles.Theheartallowsthesechamberstofillwithbloodandthenitpumpsthebloodaroundthebody.Theheartisconnectedtoanelaboratesystemofbloodvessels.Themainarteryiscalledtheaorta,whichisjoinedtothetopoftheheartandservestotakethebloodawayfromtheatria.Twolargeveins,knownasthesuperiorvenacavaandtheinferiorvenacava,carrybloodtotheheart.Thepumpingactionisproducedbyamuscleintheheart,calledthecardiacmuscle.Aheartbeatisacontractionofthismuscleasitforcesbloodthroughthechambersoftheheartandintotheaorta.Theheartperformsthispumpingactionmorethantwoandahalfbilliontimesinanaverageperson'slifetime,beatingataround70beatsaminute.Vigorousexercise,suchasrunning,putsmoredemandsonyourheart.Yourbodyneedsmoreenergyfromblood,sotheheartneedstopumpfaster.Whenyourelax,orsleep,theheartisabletoslowdown.Becauseofitsimportance,theheartisverycarefullylocatedinthebody.Itisshieldedbythestrongbreastboneandtheribcage,andprotectedbelowbythepowerfulmusclesofthediaphragm.Thisprotectionmakesitdifficultfordoctorstomonitoritscondition.Specialtechniques,suchasx-rayscanning,havebeendevelopedtochecktheperformanceofthemuscle.Thecommonestheartproblemsarearrhythmia(心律不齐),whichisanirregularheartbeatpattern,andamurmur(杂音),whichoccurswhenthewallsbetweenthechambersoftheheartareveryweak,allowingbloodtopassthroughfromonechambertothenext.Thebestwaytokeepyourheartingoodshapeistotakeplentyofexerciseandtoeathealthyfood.(403words/_____minutes)Vocabularyemotion情感gratitude感激之情heartfelt衷心的，诚挚的fainthearted胆怯的；无决断的chamber室，腔atria心房ventricle心室elaborate精巧的；复杂的vessel血管；脉管artery动脉aorta王动脉vein静脉superiorvenacava上腔静脉inferiorvenacava下腔静脉cardiac心脏的muscle肌；肌肉heartbeat心搏；心跳声contraction收缩vigorous强劲的；有力的shield保护breastbone胸骨ribcage胸腔diaphragm膈；隔膜NoteManyEnglishwordsinbiology,suchasatria,aortaandvenacava,aretakenfromtheLatinlanguage(拉丁文).Exercise1Answerthesequestions.1.Howmanychambersarethereinaheart?2.Howbigisyourheart?3.Howmanyveinscarrybloodtotheheart?4.Howmanytimesdoesaheartbeatinaminute?5.Whydoesyourheartbeatfasterwhenyoudovigorousexercise?Exercise2Matchthewordsandthedescriptions.WordDescription1.aorta2.atria3.ventricles4.inferiorvenacava5.arrhythmia6.murmurAirregularheartbeatBthelowerchambersoftheheartCthearterythattakesbloodfromtheheartDaveinthatbringsbloodtotheheartEbloodpassingthroughaweakheartwallFtheupperchambersoftheheartReading(2)AhearttransplantIfaperson'sheartisbadlydiseasedandheartsurgerycannotrepairthedamage,atransplantmaybenecessary.Atransplantinvolvestakingthehealthyheartofsomeonewhohasrecentlydied,andplacingitinthepatientasareplacementforthediseasedheart.Duringtheoperation,thepatientisattachedtoaheart/lungmachine.Thismachineactsinsteadoftheheartinpumpingbloodaroundthebody.Next,surgeonsremovethediseasedheart,leavingjustthebackwallsoftheatria.Thenewheartissewntothesewalls,onceitsownbackwallshavebeenremoved.Thenextphaseistogetthenewheartworking.Thebloodvesselsareattachedand,asbloodstartsflowing,theheartstartstobeatregularly.Iftherearenoproblems,thesurgeonswillremovethepatientfromtheheart/lungmachineandclosethechest.Thewholeoperationtakesaboutsixhours.(156words/________minutes)Vocabularysurgery手术transplant移植diseased有病的；不健全的replacement代替；更换；替补attach连接remove去掉；切除phase阶段Exercise3Numbertheseactionsintothecorrectorder.StepsinahearttransplantThenewheartisattachedtotheoldbackwallsoftheatria.Thesurgeonsclosethepatient'schest.Thepatientisattachedtoaheart/lungmachine.Thediseasedheartisremovedfromthepatient.Thenewheartstartsbeating.Thehealthyheartisremovedfromadeadbody.Thebloodvesselsareconnectedtothenewheart.____________________________________________________________________________________Exercise4Herearesomeinterestingfactsabouttheheart.Findoutsomemoreandaddthemtothelist.Heartfacts●Theaortamthelargestarteryinthebody--isasthickasyourthumb.●Youhaveaboutlitresofblood,whichcirculatesthroughyourbodythreetimeseveryminute.●Inanaveragelifetime,theheartpumpsImillionbarrelsofbloodthroughthebody.