【尚友制造】36套阅读解析exer25

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1、www.sharewithu.comExercise25Since1953,manyexperimentalattemptstosynthesizethechemicalconstituentsoflifeunder"primitiveEarthconditions"havedemonstratedthatavarietyofthecomplexmoleculescurrentlymakinguplivingorganismscouldhavebeenpresentintheearlyoceanandatmosphere,wi

2、thonlyonelimitation:suchmoleculesaresynthesizedfarlessreadilywhenoxygen-containingcompoundsdominatetheatmosphere.ThereforesomescientistspostulatethattheEarth'searliestatmosphere,unlikethatoftoday,wasdominatedbyhydrogen,methane,andammonia.Fromthesestudies,scientistsh

3、aveconcludedthatthesurfaceoftheprimitiveEarthwascoveredwithoceanscontainingthemoleculesfundamentaltolife.Although,atpresent,scientistscannotexplainhowtheserelativelysmallmoleculescombinedtoproducelarger,morecomplexmolecules,somescientistshaveprecipitouslyventuredhyp

4、othesesthatattempttoexplainthedevelopment,fromlagermolecules,oftheearliestself-duplicatingorganisms.(138words)1.Accordingtothepassage,whichofthefollowingcanbeinferredabouttheprocessbywhichthechemicalconstituentsoflifeweresynthesizedunderprimitiveEarthconditions?(A)T

5、hesynthesisisunlikelytooccurundercurrentatmosphericconditions(B)Thesynthesisiscommoninmodernlaboratories.(C)Thesynthesisoccursmorereadilyintheatmospherethanintheocean.(D)Thesynthesiseasilyproducesthemostcomplexorganicmolecules.(E)Thesynthesisisacceleratedbythepresen

6、ceofoxygen-containingcompounds.2.Itcanbeinferredfromthepassagethat"somescien-tists"assumewhichofthefollowingconcerning"larger,morecomplexmolecules"(A)Theearliestatmospherewasforwardprimarilyofthesemolecules.(B)Chemicalprocessesinvolvingthesemoleculesproceededmuchmor

7、eslowlyunderprimitiveEarthconditions.(C)Thepresenceofthesemoleculeswouldnecessarily本文由尚友原创或整理1www.sharewithu.comprecedetheexistenceofsimpleorganisms.(D)Experimentaltechniqueswillneverbesufficientlysophisticatedtoproduceinthelaboratorysimpleorganismsfromthesechemical

8、constituents.(E)Explanationscouldeasilybedevelopedtoexplainhowsimplemoleculescombinedtoformthesemorecomplexones.阅读1：参考翻译：1953年以来，科学家们做了大量实