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1、TranslationOncetheDNAcodehasbeenTranscribedontoamRNAmolecule,mRNAleavesthenucleusandmovesintothecytoplasm.InthecytoplasmthemRNAcombineswiththeRibosomestomakeEnzymes/Proteins.TheProcessofreadingthemRNAcodeandbuildinga(n)Enzyme/ProteiniscalledTranslation,orProteinSynthesis
2、.InorderforTranslation/ProteinSynthesistooccuracellneeds:1.mRNA(carryingtheDNAcode)2.Ribosomes3.AminoAcids4.tRNA(picksupaminoacidsinthecytosolandcarriesthemtotheribosomeswheretheywillbejoinedtogethertoformaProtein)ThemRNAismadeintheNucleusthroughtheprocessofTranscription
3、.mRNAismadeupofRNAnucleotides.Eachgroupof3nucleotidesiscalledaCodonandcodesforoneaminoacidofthenewlyformingProtein.ThisSegmentofamRNAmoleculeis7codonslong,21nucleotides,andwillcodefor7aminoacidsRibosomes(theribosomesaretheactualsiteofTranslation/proteinsynthesis)Madeinth
4、eNucleolus,madeupofRibosomalRNA,rRNAAnimalsandPlantsgettheiraminoacidsthesamewaytheygettheirNucleotides.TransferRNA(tRNA)tRNAisasmall,foldedRNAchain(74-93nucleotides)thatpicksupandtransfersspecificaminoacidstoagrowingpolypeptidechainattheribosomalsiteofproteinsynthesisdu
5、ringtranslation.IthassitesforAminoAcidattachmentandanAnticodon.TheAnticodoniscomposedofcomplementarybases.EachtRNAmoleculebindstoonlyonetypeofaminoacid.MorethanonetRNAexistsforeachaminoacid.SummaryofTranslation(or…soyouwanttomakeaProtein)Let’sbegininthenucleus……TheDNAhas
6、thecodetoinstructtheRibosomesastowhichProteinstomake.Ok,2problemshere:1.)theDNAisintheNucleusandtheribosomesareintheCytoplasm,and2.)theribosomescan’treadtheDNA.Wellthere’saneasywaytofixbothproblems…it’scalledTranscription….ThroughTranscription,theDNAcodeisplacedontoamRNA
7、moleculewhichcan1.)leavethenucleus,travelintothecytoplasmandjoinwiththeribosomes,and2.)theribosomescanTranslate(read)themRNA.SonowwehavetheDNAcode,bywayofmRNA,inthecytoplasmthatcaninstructtheRibosomesastowhichproteintomake…..Bytheway,thedifferencebetweenoneproteinandanot
8、herproteinistheorderoftheaminoacids,thenumberofaminoacidsandits3dimensionalshape.Now……let’ssayyouareari