英語聽力教程LTW2Unit7課件

Unit7

AboutYourselfPartIGettingreadyPartIIThedigestivesystemanddiarrheaPartIIIImmunityPartIVMoreaboutthetopic:WhyDoICatchColds?PartVMemorytest:DentalHealthPartVIWatchandenjoyListenThisWayBook2PartIGettingreadyOurbodyismadeupofdifferentparts,suchasface,handsandfeet.Bodywordshavebeenwidelyusedfigurativelyinsomephrases.Andthesephrasesoftencreateveryvividimages.*figuratively象征性地，比喻地A.Thefollowingwordswillappearinthisunit.Listencarefullyandstudythedefinitions.1.grindtoahalt:停止2.abdomen:腹部3.coilup:盤卷，盤繞4.dehydrate:脫水5.contaminatedfood:不潔食物6.bacteria:細(xì)菌7.virus:病毒8.reserve:儲(chǔ)藏9.lash:猛擊10.infect:傳染，感染11.gum:齒齦12.wig:假發(fā)B.Youaregoingtohearseveralshortdialogues.Payattentiontothenumbersandthebodywordsinthephrases.Thenguessthemeaningofthesephrases.1.A:Doyouknowhowmany_____you’vegot?B:Howmanyteeth?Ooh,ooh.____?More?(A:Yes)___?A:Yes.2.A:Doyouknowhowmanybonesthereareinyourbody?B:Howmanybones?I’lltakeaguess.____.A:____.3.A:Howoftendoesyourheartbeat?B:__timesaminute.A:No,___timesaminute.20670981533224teeth4.Bob:Doyouknowwhatthebossthinksyoushoulddo,Billy?Billy:Justyoukeepyourgreat_____outofthis,Bob,willyou?(Meaning:_____________)5.Anne:StevenKent,Inever,neverwanttoseeyouinmylifeagain.Steven:Ohno.Mary:Youreallyhaveputyour_____init,haven’tyou?(Meaning:___________________________________________)6.Kate:Dave!Canyougivemea______,please?Dave:What?Kate:Isaid“canyougivemea_____?”Dave:Allright,I’mcoming.Noneedtoshout.(Meaning:__________)askforhelphandcauseembarrassmentbydoingorsayingsthtactlessfootnotinterfereinnosehand*interferein干預(yù)，干預(yù)*tactless

不機(jī)智的，笨拙的7.Max：Arethereanyjobsgoinginyourcompanythen,foranintelligent,hard-workingyoungmanlikemysonJulian?Frank:No,Ihaven’theardofanyatallrecently.Max:Well,couldyoukeepyour_____open,justincase?(Meaning:_____________)8.Carol:HaveyouheardaboutMaggiethen?Norma:Maggie?MaggieThatcher?Carol:No.MaggieBrown.She’sinloveagain.Norma:Ohnotagain.Whowiththistime?Carol:Withherboss.______overheelsinlovewithhim,sheis.(Meaning:__________)listenwithcare*justincase以防萬一Headearscompletely*heel腳后跟9.Nick：HaveyoueverlentanymoneytoMick?Jill:Mick?Huh!Iwouldn’tlendhimanyifIwereyou.Nick:Whynot?Doesn’thepayitback?Jill:No.Never.He’suptohis______indebts.(Meaning:________________)10.Liz:She’saverygooddoctor.Neverlooksatherwatch.Nevercomplains.Nothing’stoomuchtroubleforher.Pat:Iknow,yeah.Notmanylikeherabout.She’sall______,really.All_______.(Meaning:_____________________)withthedeepestdevotiondeeplyinvolvedinheartneckheartC.Nobody'sreallysurewhypeoplegobald,butsomescientistsbelievethatpeoplemayinheritbaldness.Ifyouareinterested,checkoutyourmother'sfather.Yourhairlinemaylooklikehiswhenyougetolder.Nowlistentoaradiophone-in.Completethefollowingchart.*gobald謝頂，禿頂*inherit繼承*hairline發(fā)際線Caller’snameProblemCaller’sdoctor’sopinionSolutionAdvice*hereditary遺傳*shampoo香波，洗發(fā)水*thinpatch頭發(fā)稀少的區(qū)域*falsehairpiecething=wig假發(fā)don’tcombitover;don’twearanyfalsehairpiecethingsnotalothecandoaboutit;trytoacceptnothinghecandoaboutit;hereditarylosinghairJimBaillieAudioscriptHomepagePartIIThedigestivesystemanddiarrheaThehumanbodyisahighlycomplexself-generator,thatistosay,provideditisgiventherightfuel,itiscapableofbothcuringandwardingoffdisease.Thefoodweeathelpstogiveusenergy.Ithasalongjourneytomakebeforeallitsgoodnesshasbeentakenintoourbody.Thefoodtakesuptosixhourstobedigestedinthestomach,dependingonthesizeofthemeal.Thecompletedigestiveprocesstakesabout24hours.Butsometimesthesystemcangowrong.*digestivesystem消化系統(tǒng)*diarrhea腹瀉，拉肚子*self-generator自愈體*wardingoff阻擋〔疾病〕*digested消化*stomach胃*completedigestiveprocess整個(gè)消化過程A.Youaregoingtohearatalkonthedigestivesystemanddiarrhea.Whilelisteningforthefirsttime,addmorekeywordsinthenotescolumn.Afterthesecondlistening,matchcolumnAwithcolumnBwiththehelpofthenotes.*inexpertly不熟練地，外行地*over-taxed稅負(fù)過重的，過度透支的*insufficientlyused使用不當(dāng)?shù)?rusty遲鈍的，衰退的*sluggish懶怠的，無活力的*clogged阻塞的，不通暢的*mechanism機(jī)械裝置*rawmaterial原材料*tissue人體組織*squeeze擠壓*muscle肌肉*thewalloftheintestine腸壁*feces糞便*bowel腸道*clearup治愈，痊愈*fluid水分*dehydrated/dehydration脫水ColumnAColumnB1.gutsymptoms__absorbingdigestedfoodintobloodstream__contaminatedfood2.thedigestivesystem__drinkingenough__alongtubecoilingupintheabdomen3.causesofdiarrhea__carryingawaywasteproducts__constipation4.jobsofthedigestivesystem__infectionbyvirusesorparasites__breakingdownfood5.treatmentfordiarrhea__addingenzymes__diarrhea4253414314*腸道病癥*bloodstream

血流*wasteproducts排泄物*便秘*感染*寄生蟲*病毒*分解食物*enzyme酶AudioscriptB．Nowtrythis:listentoamoreauthenticversionofthetalk.Focusonthecausesandtreatmentsofdiarrhea.Completethestatements.CausesofdiarrheaThereareinfections,andthisis____________,whichiscausedbysomesortofbacteriaororganisms.Somefoods_________mightirritate_______andtendtogiveyoudiarrhea.Somepeoplewhenthey______________and_____________________tendtogetdiarrhea.Peoplewhosufferfromtheirritablebowelsyndrometendtogettummypainsand________.*foodpoisoning食物中毒*bacteria細(xì)菌*organisms生物體，有機(jī)體*irritate刺激，使過敏，使發(fā)炎*irritablebowelsyndrome腸激惹綜合征*tummypain肚子痛thegutthemselvesfoodpoisoningdiarrheastressedaboutsomethinggetverynervousTreatmentofdiarrheaMostattacksofdiarrheaarenot_______andthey________bythemselveswithin_____________.Themostimportantthingisto______________.Itisbetternotto____________andnottoworryaboutthat.Ideally,thefluidsyoudrinkshouldcontainalittlebitof______________.Youcangetspecialrehydratingfluids,whichare_____________.Youcangetyourownfluidsbyaddingjustateaspoonfulof________________________.sugarandapinchofsaltspeciallymixedsaltandsugareattoomuchdrinklotsoffluidoneortwodaysclearupserious*attacksofdiarrhea腹瀉病發(fā)*rehydratingfluids再水合劑*apinchof一小撮AudioscriptHomepagePartIIIImmunityTheenvironmentcontainsmanypotentiallydestructivemicroorganisms.Itisimpossibleforustoavoidcontactwithmicrobes.That'swhyourbodyisconstantlyunderattackfrominvadinggermsandinfections.Thenwhydon'twesufferfromconstantillness?Dowehaveourowndefensesystem?*immunity免疫力*microorganisms微生物*microbes微生物，細(xì)菌A．Thefollowingwordsandphrasesareusedinadiscussionontheimmunesystem.Listentothewordsandphrasesfirst.Studythedefinitionscarefully.1.germ:微生物，細(xì)菌2.defensesystem:防御系統(tǒng)3.cell:細(xì)胞4.whitebloodcell:白細(xì)胞，白血球5.molecule:分子6.bonemarrow:骨髓7.antibody:抗體8.measles:麻疹9.polio:小兒麻痹癥10.tuberculosis:肺結(jié)核11.AIDS:艾滋病B．Nowlistentothefollowingdiscussion.Whilelisteningforthefirsttime,addmorekeywordsintheleft-handcolumn.Afterthesecondlistening,answerthequestions.NotesQuestionsimmunity:defensesystem1.Sincewehavetheimmunesystem,whydowestillneedvaccinations?______________________________________________________________________headquarters:bloodtroops:cells

reserve:bone

marrow

whitecells:gobble

up;memorynotworkingwell

overactive—

underactive—2.Howdoesavaccinationwork?_______________________________________________________________________________________________________________________________________________________________________________Becausetherearesomethingswhich we’renotnaturallyimmuneto.Aversionofanillnessisgivento thebody,andthebodythinksthatitisactuallybeinginfectedwiththatinfection.Thenexttimeitseesit,thebodycanrespondveryquickly.*免疫系統(tǒng)*疫苗接種*細(xì)胞

*不夠活潑的*過于活潑的*狼吞虎咽

*骨髓

NotesQuestionsvaccination:notimmune;remember;versionofillness3.Canweproducevaccinesforanydisease?Giveanexample.____________________________________________________________AIDS:HIV;attackimmunesyst.;changeeasily4.WhyisitsodifficulttoattackAIDS?____________________________________________________________________________________________________________________________________________________________________________________*protein蛋白質(zhì)*invader入侵者*comeintoplay開始起作用*turnon突然襲擊*multiple-sclerosis多發(fā)性硬化TheHIVvirus,whichcausesAIDS,attacksthehumanimmunesystem.Andthevirusitselfcanchangeveryeasily.It’sverydifficulttofindavaccinewhichcanrecognizealltypesofHIV.No.Wecan’tproduceavaccinefor AIDSforinstance.*疾病種類AudioscriptC.Nowtrythis:listentoamoreauthenticversionofthediscussion.Completethediagram.Thenputthenumberofeachphrasebelowintheproperplace.*familydoctor家庭保健醫(yī)生*backup后援，援助*tiedup忙得不可開交的*makeup構(gòu)造*atgreaterrisk處于更危險(xiǎn)的境地bloodmorelikelytobeinfectedinvadersinvadersthevirusthatcausesAIDSrememberingthechemicalmakeupofinvadinggermsandattackingthemveryquicklyfightinginvadingdiseasedestroyingthebody’simmunesystemprotectingthebodyagainstspecificinfectionsputtingthebodyatgreaterriskfromothercommoninfections1.2.3.4.5.6.theimmunesystem________________________________

vaccination______________________________HIV____________________________532641AudioscriptHomepagePartIVMoreaboutthetopic:WhyDoICatchColds?Acoldisamildviralinfectiousdiseaseofthenoseandthroat,theupperrespiratorysystem.Symptomsofacoldincludesneezing,sniffing,running/blockednose,scratchy,sore,orphlegmythroat,coughing,headache,andageneralfeelingofunwellness;theylastbetween3to10days,withresidualcoughinglastingupto3weeks.Itisthemostcommonofalldiseases,infectingsubjectsatanaverageofslightlyoveroneinfectionperyearwithgreaterthan3infectionsperyearnotuncommoninsomepopulations.*viralinfectiousdisease病毒感染類疾病*upperrespiratorysystem上呼吸系統(tǒng)*sneezing打噴嚏*sniffing抽鼻子*running/blockednose流鼻涕/鼻塞*scratchy/sore/phlegmythroat咽喉刺癢/疼痛/多痰*unwellness不舒服*residualcoughing感冒好了之后的咳嗽*subjects病人，患者Thefollowingmonologueisaboutacommondisease—cold.Listencarefullyandsupplythemissinginformation.

Virusesaremostdefinitelygoingtogetyou.Andwhentheydo,theywillgiveyouanything,fromacoldtoEbola.Andyet,________,viruseshavenolife_________.Sowhydotheycausesomuchtrouble?______________,whydoIcatchcolds?Seethatguywiththe_______nose.Whenhe________,______dropletswillflytwelvefeetintotheair,infectingupto____people.Youshouldhave______.Acoldvirusjustcan’tlivewithoutyou.Withnocellsofitsown,itneedsto________yourcellsandreplicate.Here’ssomethingtothinkabout.takeoverducked15040,000sneezesblockedMoretothepointoftheirowntechnically*Ebola埃博拉*droplet小滴*replicate復(fù)制technically嚴(yán)格意義上Moretothepoint說得更確切些*duck低頭Theviruscanonlytravelaroundinsideablobofmucus.Andthatmeanswheneveryoucatcha_______,someoneelse’ssnothasbeenupyournose.Anyway,your_____________isconstantlyontheprowlforattackerslikethese.Ifitwasn’t,youcould__________fatalpneumonia.So,whenitspotsaviralinvasion,itgrabsa_______andtakesittothenearestlymphnode,homeofyourkillerTcells.Here,aTcellfirstidentifiestheinvaderandthendeploysanarmyoftailor-madeimmunecellstoyournose.Theseprovidespecialist________forthestandardimmunecellsalreadyfightingyourcold.Yournosehasbecomeabattleground.backupsampleendupwithimmunesystemsniffle*ablobofmucus一滴粘液*snot鼻涕*ontheprowl徘徊，逡巡*fatalpneumonia致命的肺結(jié)核*spot發(fā)現(xiàn)*lymphnode淋巴結(jié)*deploy部署*tailor-made量身定制的*sniffle鼻塞，感冒

Meanwhile,tostopinfectionspreadingtoyourlungs,you’remanufacturingadailypintofmucus.Thissnotgivesyoua________.Whilethevirusirritatesyournose,soyouhaveto_____itaround45timesaday.Beatingacoldtakesyouaboutsevendaysandyou’llcatchaboutfourayear.Thisis_____________forthecoldvirus.Ithopsonplaneswithitshuman_____,visitsnewcitiesandfindshundredsofnewhomeswitheverysneeze.Asitreplicates,itmutates.Sobythenextyearitmaybebackinadifferentform.hoststhegoldenageblowheadache*adailypintof每日一品脫*hop跳上〔飛機(jī)〕*mutate變異Homepage*blow擤〔鼻涕〕PartVMemorytest:DentalHealthIndifferentcountriesandamongdifferentpeoples,thereisawiderangeoffoodswhichcanbecombinedtoprovideabalanceddiet.Thetypeofdietapersonadoptsdependsonwhatfoodsareavailable,howmuchtheycostandonreligiousandculturalbeliefs.Butinordertoenjoythedeliciousfoods,youmusthaveastrongsetofteeth.Soitisveryimportanttokeepyourteethhealthy.*balanceddiet均衡的飲食*astrongsetofteeth一口好牙Thefollowingpassageisaboutdiseasesoftheteethandgums,andwaystopreventandtreatthem.Listencarefullyandsupplythemissinginformation.*theMaya瑪雅人〔中美洲的印第安人，在美洲被西方發(fā)現(xiàn)前已有高度文明〕瑪雅文明，是分布于現(xiàn)今墨西哥東南部、危地馬拉、洪都拉斯、薩爾瓦多和伯利茲5個(gè)國家的叢林文明。雖然處于新石器時(shí)代，卻在天文學(xué)、數(shù)學(xué)、農(nóng)業(yè)、藝術(shù)及文字等方面都有極高成就。與印加帝國及阿茲特克帝國并列為美洲三大文明〔阿茲特克帝國與瑪雅文明位于中美洲；印加帝國位于南美洲安第斯山一帶〕。AncientEgyptians:earliest_______ofdentaltreatment—treating___________byusingasubstancemadeof_______________.

—earliestknown________totreattoothproblems—livingabout______yearsago,knownasa“_______________〞Chinese:5000yearsago—treatingtoothpainby___________1300yearsago—__________intheteethwithamixtureofthemetals

—___________________Maya:makingteeth______byplacingpiecesof_____________onthemstoneandmetalpersonspicesandonionsgumswellingrecordacupuncturedoctorofthetooth5000prettymercury,silverandtinfillingholes*牙齦腫痛*香料/洋蔥*水銀(貢)，銀，錫*補(bǔ)牙齒的蛀洞*針灸AncientRomans:2000yearsago—making_________to_______thosethathadbeenlostEuropeans:

5th–15thcentury—______________performingservicesincluding_________,_________andtreatingmedicalconditions14th–15thcentury—______________improvedFrench:1700s—PierreFauchard:thefatherof______________—TheSurgeonDentist:thefirstbookabout_____________dentalsciencemoderndentistrydentaltreatmentbarber-surgeonspullingteethcuttinghairreplacefalseteeth*假牙*牙醫(yī)學(xué)*牙科醫(yī)術(shù)*(舊時(shí))兼做外科醫(yī)生和牙醫(yī)的理發(fā)師AudioscriptHomepagePartVIIWatchandenjoy*flakeoff剝落*overlap疊蓋*tightly-packedrooftiles重重疊疊的屋頂瓦片*waterproof防水的*formidablebarrier重要的屏障*flexible柔韌靈活的*inertcoating惰性的表層*vitalfunction維持生命的重要機(jī)能*heat-sensitivecamera熱敏感攝像機(jī)*internalorgan內(nèi)部器官

*sweatgland汗腺

*contract收縮*evaporate蒸發(fā)*finelytunedtechnology精美的技術(shù)*robust強(qiáng)壯的*mesh網(wǎng)狀物*collagenfiber膠原纖維*bloodvessel血管*sever切斷*healingkit治愈裝備*platelet血小板，凝血細(xì)胞*scab痂，瘡痂

1._____Thebiggestorganinthehumanbodyisskin.2._____Thepartoftheskinthatyoucanseeismadeupoflivingcells.3._____Pregnantwomenproduceahormonethatallowstheirskintostretchtotwiceitssize.4._____Abodyworkingflatoutcanexpelthreepintsofsweatperhour.5._____AstrandofcollagenisstrongerthanasteelwireofthesamedimensionsTFTFT*2.(F)Thepartoftheskinthatyoucanseeismadeupofdeadcells.*4.(F)Abodyworkingflatoutcanexpeltwopintsofsweatperhour.VideoscriptHomepage*荷爾蒙*汗水*排出*竭盡全力*一股膠原纖維*尺寸Radiopresenter:Allright.Thankyouforthatcall,Rosemary.Wegonow,Ithink,toGlasgowandournextcaller,er,JimBaillie.Hello,Jim.Jim:Hello?Radiopresenter:Hello,Jim.What’syourproblem?Jim:Er…wellI’mer…beginningtolosemyhair.Er,Iwenttothedoctor,buthejustsaidtherewasnothingIcandoaboutit.Hesaiditwasprobablyhereditary.Myfatherwasbaldbythetimehewasthirty.Maurice:Hello,Jim.Andhowoldareyou?Jim:Me.I’mtwenty-eight.Maurice:Andareyoulosingalotofhair,then?Jim:Well,itcomesoutalotwhenIcombmyhairandyoucanseeathinpartonthetopofmyhead.Maurice:Anddoesthatreallyworryyou,Jim?Jim:Well.Idon’tlikeit.It’sold…youknow…looksold…Idon’twanttolooklikeamiddle-agedmanattwenty-eight.AndIwonderediftherewassomespecialshampooIshoulduse…ifyoucouldtellmeonethatIshouldbuy…somethinglikethat…youknow…tostopitgettingworse.Maurice:Well,youknow,Jim,tobehonestwithyouthere’snotreallyalotyoucandoaboutit,actually,I’mafraid.Imean,baldnessisoneofthosethingsthat,inmyexperience,youjusthavetotrytoaccept.Somemenfinditmoredifficulttoacceptbaldnessthanothers…

Tessa:Thereisonepieceofadvice,though,Jim,andthat’sdon’ttrytocombyourhairoverthebaldorthinpatch.Don’ttrytohideit.Whateveryoudo,don’tcombitoverbecausethatusuallylooksridiculous.Andtheotherthingthatusuallylooksridiculousisamanwithawig.Don’tletanyonepersuadeyoutobuyoneofthosefalsehairpiecethings,becausetheyusuallylookmuchworsethanabaldman.Iactuallythinkbaldmencanlookveryattractive.Myhusband’sbaldandIthinkitreallysuitshim.

AudioscriptOurbodyismadeupofthousandsofdifferentparts.Allthesepartsworktogethertokeepusaliveandtohelpusmovearound.Thepartsofthehumanbodyarelikethepartsofaverycomplicatedmachine.Likeanyothermachine,however,ifitisinexpertlycaredfor,over-taxedorinsufficientlyused,itwillbecomerusty,sluggishorcloggedandpartsofitsmechanismmayevengrindtoahalt.Thatiswhyitissoimportanttokeepeverypartofthehumanmachinehealthyandproperlycaredfor.Tokeepingoodrunningorder,thebodyrequirestherawmaterialsforgrowthandthereplacementoftissueswhennecessary.Ourbodiesburnfoodlikefueltoproducetheenergyweneed.?Thehumandigestivesystemisabitlikeaverylongtube,butit’salotmorecomplex.It’sseveralmeterslong,andmostofitiscarefullycoiledupinourabdomen.Ithasseveralimportantjobstodo.?First,itmustdigestorbreakdownourfood.Digestionstartsthemomentfoodentersourmouth.Thenitcontinuesasthefoodissqueezedalongthegutbymusclesinthewalloftheintestine.Asthefoodtravelsthroughthegut,naturalchemicalscalledenzymesareaddedtoit,whichhelpbreakdownthefood.Thenthisdigestedfoodandwatermustbeabsorbedfromthegutintoourbloodstreamsothatitcanbeusedbythebody.Finally,thegutmustcarryawayanywasteproductsintheformoffeces.

Usuallyourintestinedoesallthesethingsveryefficiently.Butsometimesthingscangowrong.Probablythemostcommongutsymptomsarediarrheaandconstipation.?Withdiarrhea,thefoodandwatertravelstooquicklythroughtheintestine,oftenmakingthefeceswatery,andmakingitnecessarytoopenthebowelsmorefrequently.?Therearelotsofcausesofdiarrhea.Probablythecommonestcausesofdiarrheaarecontaminatedfoodorwater,andinfectioncausedbyvirusesorparasites.?Manycasesofdiarrheaclearupwithinafewdayswithoutanyspecialmedicines.Butthebodylosesalotoffluidthroughdiarrhea,sothereisaveryrealriskofthebodydryingoutorbecomingdehydrated.Becauseofthisriskofdehydration,thebesttreatmentfordiarrheaissimplytomakesureyouaredrinkingenough.Avoidingdehydrationinthiswaycanbealifesaver.

AudioscriptTherearelotsofdifferentcausesofdiarrhea.Um,thereareinfectionsthatcanhappen,andthisisfoodpoisoning,ifyoulike,whereinyourfoodyoueatsomesortofbacteriaororganisms,whichinfectyou.Somefoodscanjustirritatethegutandtendtogiveyoudiarrhea,althoughtheyarenotinfected.It’sjustthefooditself(that)mightirritateyoursystem.Somepeople,iftheygetverynervousandstressedaboutsomething,findtheytendtogetdiarrhea,somethingcalledtheirritablebowelsyndromewheresomethinggoeswrongwiththewaythegutworks.Andpeoplethatsufferfromthistendtoget,um,tummypains,andtheygetsometimesdiarrhea,sometimesconstipation.Allsortsofcauses.Mostattacksofdiarrhea,um,particularlyinadults,arenotseriousandtheyclearupbythemselveswithinonetotwodays.Themostimportantthingistodrinklotsoffluid,becauseifyouhavegotdiarrhea,you’reobviouslylosingalotoffluid.Andsoit’sbetterreallynottoeattoomuch,nottoworryaboutthat,buttomakesureyoudrinkplentyoffluid.Andideally,theyshouldhavealittlebitofsaltandsugarin.Youcangetspecialrehydratingfluids,whicharespeciallymixed.Butifyouwanttomakeyourownbyaddingjustateaspoonfulofsugarandapinchofsalt,thenit’sobviouslyperfectlyreasonabletodothat.AudioscriptThehumanbodyisconstantlyunderattackfrominvadinggermsandinfections.Andtheonlyreasonwedon’tsufferfromconstantillnessisourbodieshavetheirowndefensemechanismtofightoffdisease.Thisresistancetoinfectioniscalledimmunity.A:Howdoesimmunitywork?B:Well,theimmunesystemisthebody’sownsecretarmy,whichfightsinfection.Anditconsistsofawholerangeoftroops,soldiers,theircellsandtheirmolecules.Nowtheheadquartersofthisarmyisreallytheblood.That’swhereitdoesmostofitsfighting.Andsometimesitneedssomereserve,andthatcomesfromthebonemarrow.That’swheretheimmunecellsaremade.A:Sotherearemanydifferentkindsofcells,differentkindsofmoleculesintheimmunesystem.Iguessedtheonesthatwe’reprobablymorefamiliarwitharewhitebloodcells.B:That’sright.Whitebloodcellsformamajorpartofthebody’sdefense.Buttherearealsoantibodiesintheirlife,moreproteins.Theyjustlashontotheinvaders.Thewhitecellscansometimesactuallygobbleupinvaders.Thecleverthingisthatoncetheinfectionhasattackedourbody,theimmunesystemseemstohaveamemoryoftheinvader,sothatthenexttimeitseestheinvaderitcanattackveryquickly.A:Therearesomethingswhichwe’renotnaturallyimmunetoandthat’swherevaccinationcomesin,isn’tit?B:Exactly.Vaccinationplaysonthebody’sabilitytorememberinfection.Sowhathappensisthatsomeoneisgivenaversionofanillness,forinstance,measlesorpolio,ortuberculosis,andthebodythinksthatitisactuallybeinginfectedwiththatinfection.Andthenexttimeitseesit,thebodycanrespondveryquickly.Allthetroopsofitsimmunesystemcancomeintoplay.A:Nowsometimestheimmunesystemdoesn’tworkverywell,doesit?B:No.It’saremarkablycomplexsystem.Andsometimesitcangowrong.Eitheritcanbeoveractive,soitactuallystartstoattackourownbodyself,oritcanbeunderactivesometimes,andwearemorelikelytobeinfectedinthatsituation.A:Arethereanyimportantillnesseswhichresultfromtheimmunesystemsothatit’sturningonourbodiesthemselves?B:Thereare.Oneexamplewouldbeadiseaselikemultiple-sclerosis,wherethebody’sownimmunesystemattackstheliningofnerves,whichmeansthatpeople’snervesdon’tworkproperly.A:We’reabletoassistthebodyinitsfightagainsttheillnessinmanycases,buttherearesomediseaseswhichwedon’tseemtobeabletoproduceavaccinefor.AIDSisoneofthem.Whynot?B:TheproblemisAIDS,whichiscausedbytheHIVvirus,attacksthehumanimmunesystem,whichmeansthatournormaldefensesaren’ttheretofightoffthatinfection.TheotherproblemwithtryingtoproduceavaccineagainstHIVorAIDSisthatthevirus,HIV,canchangeitselfsoeasily.That’sverydifficulttofindavaccinewhichcanrecognizeallthedifferenttypesofHIV.Soonevaccinemaybeeffectiveagainstonetypeofthevirusbutitmayabsolutelybenogoodforanothertype.AudioscriptPresenter:Thehumanbodyisconstantlyunderattackfrominvadinggermsandinfections.Andtheonlyreasonwedon’tsufferfromconstantillnessisourbodieshavetheirowndefensemechanismtofightoffdisease.Thisresistancetoinfectioniscalledimmunity.AndherewithmetodiscusshowitworksisGrimeEaston.Heisafamilydoctor,andamemberoftheScienceInIt〞hereintheBBCWorldService.Grime,howdoesimmunitywork?Grime:Well,theimmunesystemisthebody’sownsecretarmy,ifyoulike,whichfightsinfection.Anditconsistsofawholerangeoftroops,soldiers,theircellsandtheirmolecules.Um,nowtheheadquartersofthisarmyisreallytheblood.That’swhereitdoesmostofthefighting.Andsometimesitneedssomereserve,somebackup,andthatcomesfromthebonemarrow.That’swheretheimmunecells’factoriesare.Presenter:Sotherearemanydifferentkindsofcells,anddifferentkindsofmoleculestiedupintheimmunesystem.Iguessedtheonesthatwe’reprobablymorefamiliarwitharewhitebloodcells.Grime:That’sright.Thewhitebloodcellsformamajorpartofthebody’sdefense.Buttherearealsoantibodiesintheirlife,moreproteins,whichjustlashontotheinvaders.Um,but,asyousay,thewhitecellscansometimesactuallygobbleupinvaders.Sothecleverthingisthatoncetheinfectionhasattackedourbody,theimmunesystemseemstohaveamemoryoftheinvader,sothatthenexttimeitseestheinvaderitcanattackveryquickly.Theimmunesysteminthehumanbodyfightsinvadingdisease.Immunityoccursbecausetheimmunesystemcanrememberthechemicalmakeupofinvadinggermsandattackthemveryquickly.Presenter:Therearesomethingswhichwe’renotnaturallyimmunetoandthat’swherevaccinationcomesin,isn’tit?Grime:Exactly.Vaccinationp