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1、CellsCellsTemperatureTemperature細(xì)胞與溫度細(xì)胞與溫度muchnarrowerlimitsmarktheboundariesofeffectivefunctioning.Enzymesystemsofmammalsbirdsaremostefficientonlywithinanarrowrangearound37Cadepartureofafewdegreesfromthisvalueseriouslyi

2、mpairstheirfunctioning.Eventhoughcellscansurvivewiderfluctuationstheintegratedactionsofbodilysystemsareimpaired.Otheranimalshaveawidertolerancefchangesofbodilytemperature.Fcenturiesithasbeenrecognizedthatmammalsbirdsdiff

3、erfromotheranimalsinthewaytheyregulatebodytemperature.Waysofacterizingthedifferencehavebecomemeaccuratemeaningfulovertimebutpopularterminologystillreflectstheolddivisioninto“warmblooded”“coldblooded”specieswarmbloodedinc

4、ludedmammalsbirdswhereasallothercreatureswereconsideredcoldblooded.Asmespecieswerestudieditbecameevidentthatthisclassificationwasinadequate.Afencelizardadesertiguana—eachcoldbloodedusuallyhasabodytemperatureonlyadegreetw

5、obelowthatofhumanssoisnotcold.Therefethenextdistinctionwasmadebetweenanimalsthatmaintainaconstantbodytemperaturecalledhome0thermsthosewhosebodytemperaturevarieswiththeirenvironmentscalledpoikilotherms.Butthisclassificati

6、onalsoprovedinadequatebecauseamongmammalstherearemanythatvarytheirbodytemperaturesduringhibernation.Furthermemanyinvertebratesthatliveinthedepthsoftheoceanneverexperiencechangeinthedepthsoftheoceanneverexperiencechangein

7、thechillofthedeepwatertheirbodytemperaturesremainconstant.細(xì)胞只能在一定的溫度范圍內(nèi)存活，而進(jìn)一步保證它們有效工作的溫度范圍就更小了。哺乳動(dòng)物和鳥類的酶系統(tǒng)只能在37℃左右的很小范圍內(nèi)才能有效工作。與此相差僅幾度的溫度都會(huì)大大削弱它們的工作效率。盡管溫度變化更大時(shí)細(xì)胞仍能存活，但機(jī)體系統(tǒng)的整體運(yùn)行能力卻被削弱了。其它動(dòng)物對(duì)體溫的變化有更強(qiáng)的適應(yīng)性。幾個(gè)世紀(jì)以來(lái)，人們就認(rèn)識(shí)到哺乳動(dòng)

8、物和鳥類調(diào)節(jié)體溫的方式與其它動(dòng)物不同。隨著時(shí)間的推移，人們對(duì)這種差異的描述越來(lái)越精確和有意義，但是“暖血?jiǎng)游铩昂汀袄溲獎(jiǎng)游铩斑@一古老的分類方式至今仍在大眾詞匯中有所反映。暖血?jiǎng)游锇ú溉閯?dòng)物和鳥類，其它動(dòng)物統(tǒng)統(tǒng)被視為冷血?jiǎng)游?。但是?duì)更多物種進(jìn)行的研究表明這種分類顯然是不適當(dāng)?shù)?。美洲一種小型蜥蜴和沙漠鬣蜥同屬冷血?jiǎng)游?，但?shí)際上它們的體溫通常只比人類的體溫低1～2度，因此并不是真正的冷血。因此又出現(xiàn)了恒溫動(dòng)物(即保持恒定體溫的動(dòng)物)和變溫動(dòng)

9、物(即體溫隨外界環(huán)境的變化而改變的動(dòng)物)這一區(qū)分方式。但這種分類也不恰當(dāng)。因?yàn)橛胁簧俨傅悴⒉皇钦苟急３诌@種沉睡狀態(tài)。入睡后約但你并不是整夜都保持這種沉睡狀態(tài)。入睡后約8080分鐘左右，你的大腦運(yùn)動(dòng)水分鐘左右，你的大腦運(yùn)動(dòng)水平會(huì)再度略有提高。平會(huì)再度略有提高。δ節(jié)奏消失，并被腦電波的運(yùn)動(dòng)圖形取代。你的眼睛會(huì)節(jié)奏消失，并被腦電波的運(yùn)動(dòng)圖形取代。你的眼睛會(huì)在閉著的眼瞼下迅速轉(zhuǎn)動(dòng)，就好象你在看著眼前發(fā)生的什么事情。這種迅速的閉著的眼瞼下迅速

10、轉(zhuǎn)動(dòng)，就好象你在看著眼前發(fā)生的什么事情。這種迅速的眼球運(yùn)動(dòng)持續(xù)約眼球運(yùn)動(dòng)持續(xù)約8～1515分鐘，這一階段睡眠被稱之為快速眼動(dòng)分鐘，這一階段睡眠被稱之為快速眼動(dòng)(REM)(REM)睡眠。在睡眠。在REMREM睡眠階段，你的肢體會(huì)很快再度放松，呼吸也再次放慢并變得有節(jié)奏，你睡眠階段，你的肢體會(huì)很快再度放松，呼吸也再次放慢并變得有節(jié)奏，你會(huì)輕松地從第一階段滑入第四階段睡眠會(huì)輕松地從第一階段滑入第四階段睡眠直到大約直到大約8080分鐘后重新接近

11、清醒狀態(tài)。分鐘后重新接近清醒狀態(tài)。FolkFolkCulturesCultures民間文化民間文化(4)Afolkcultureisasmallisolatedcohesiveconservativenearlyselfsufficientgroupthatishomogeneousincustomracewithastrongfamilyclanstructurehighlydevelopedrituals.derismaintain

12、edthroughsanctionsbasedinthereligionfamilyinterpersonalrelationshipsarestrong.Traditionisparamountchangecomesinfrequentlyslowly.Thereisrelativelylittledivisionoflabintospecializedduties.Rathereachpersonisexpectedtoperfma

13、greatvarietyoftasksthoughdutiesmaydifferbetweenthesexes.Mostgoodsarehmadesubsistenceeconomyprevails.Individualismisweaklydevelopedinfolkculturesasaresocialclasses.Unalteredfolkculturesnolongerexistinindustrializedcountri

14、essuchastheUnitedStatesCanada.PerhapsthenearestmodernequivalentinAngloAmericaistheAmishaGermanAmericanfarmingsectthatlargelyrenouncestheproductslabsavingdevicesoftheindustrialage.InAmishareashsedrawnbuggiesstillserveasal

15、ocaltransptationdevicethefaithfularenotpermittedtoownautomobiles.TheAmish’scentralreligiousconceptofDemut“humility”clearlyreflectstheweaknessofindividualismsocialclasssotypicaloffolkculturesthereisacrespondingstrengthofA

16、mishgroupidentity.RarelydotheAmishmarryoutsidetheirsect.ThereligionavarietyoftheMennonitefaithprovidestheprincipalmechanismfmaintainingder.Bycontrastapopularcultureisalargeheterogeneousgroupoftenhighlyindividualisticapro

17、nouncedmanyspecializedprofessions.Secularinstitutionsofcontrolsuchasthepolicearmytaketheplaceofreligionfamilyinmaintainingderamoneybasedeconomyprevails.Becauseofthesecontrasts“popular”maybeviewedasclearlydifferentfrom“fo