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1、2013年12月英语六级选词填空习题及答案(1)Anovelwayofmakingcomputermemories,usingbacteria FORhalfacentury,the(1)__________ofprogressinthecomputerindustryhasbeentodomorewithless. Moore'slawfamouslyobservesthatthenumberoftransistorswhichcanbecrammedintoagivenspace(2)__________every18months. The
2、amountofdatathatcanbestoredhasgrownatasimilarrate. Yetas(3)__________getsmaller,makingthemgetsharderandmoreexpensive. OnMay10thPaulOtellini,thebossofIntel,abigAmericanchipmaker,putthepriceofanewchipfactoryataround$10billion. HappilyforthosethatlackIntel'sresources,theremayb
3、eacheaperoption—namelytomimicMotherNature, whohasbeenbuildingtiny(4)__________,intheformoflivingcellsandtheircomponents,forbillionsofyears,andhasthusgotrathergoodatit. ApaperpublishedinSmall,ananotechnologyjournal,setsoutthelatestexampleofthe(5)__________. Init,agroupofrese
4、archersledbySarahStanilandattheUniversityofLeeds,inBritain,describeusingnaturallyoccurringproteinstomakearraysoftinymagnets, similartothoseemployedtostoreinformationindiskdrives. Theresearcherstooktheir(6)__________fromMagnetospirillummagneticum,abacteriumthatissensitivetoth
5、eEarth'smagneticfieldthankstothepresencewithinitscellsofflecksofmagnetite,aformofironoxide. Previousworkhasisolatedtheproteinthatmakestheseminiaturecompasses.Usinggeneticengineering,theteammanagedtopersuadeadifferentbacterium—Escherichiacoli,aubiquitouscritterthatisaworkhorse
6、ofbiotechnology—to(7)__________thisproteininbulk. Next,theyimprintedablockofgoldwithamicroscopicchessboardpatternofchemicals. Halfthesquarescontainedanchoringpointsfortheprotein. Theotherhalfwereleftuntreatedascontrols. Theythendippedthegoldintoasolutioncontainingtheprotei
7、n,allowingittobindtothetreatedsquares,anddunkedthewholelotintoaheated(8)__________ofironsalts. Afterthat,theyexaminedtheresultswithanelectronmicroscope. Sureenough,groupsofmagnetitegrainshadmaterialisedonthetreatedsquares,shepherdedintoplacebythebacterialprotein. Inprincipl
8、e,eachofthesemagneticdomainscouldstoretheoneorthezeroofabitof
