Rosalind Franklin Watson and Crick Fredrick Griffith Irwin...

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FamousScientists-Belowisalistofscientistswelearnedaboutthischapter.Giveabriefexplanationoftheirexperimentorwhattheydidforgeneticresearch.RosalindFranklinWatsonandCrickFredrickGriffithIrwinChargraffMarthaHersheyandAlfredChaseMesselsonandStahlAvery,MacLeodandMcCarthyBrieflydescribeconjugation,transformationandtransductioninbacteria.Whatistheultimategoalofallthreeofthem?

Howdidyouusetransformationinthelab?Howarethebacteriadifferent?Howwilltheylookonanutrientagarplate?AgarAgarwithampicillinAgarwithkanamycinEcoliEcoliw/amprEcoliw/kamrWhyisthefirstcolumnnotausefulcomparison?DNAandDNAReplicationListthebasicpartsofanucleotide.Howcanyoutellthe5’and3’endsofaDNAstrand?

HowisDNAdifferentfromRNA?WhatdeterminesthefactthatDNAhasanoverallnegativecharge?HowdoesgelelectrophoresisworkandwhatisneededtobreakuptheDNAintofragments?WhendoesacellreplicateitsDNA?WheredothenucleotidescomefromthatwillultimatelyformthenewDNAstrandcomefrom?Isitpossiblethenewnucleotideswillshowupineachofthenewstrands?Explain.Howaretheleadingandlaggingstrandsdifferent?

CompletelydescribeDNAreplication.Besuretoincludewordslike:DNAPolymeraseIII,RNAPrimase,RNAPrimer,DNAPolymeraseI,OkasakiFragments,Nucleotides,Helicase,Topoisomerase,HydrogenBonds,Antiparallel,Semi-conservativeandDNALigase.WhatcanbesaidabouteachnewDNAmolecule?HowcanthePolymeraseChainReaction(PCR)beusedtospeedthisprocessup(replication)?

HowdoesPCRworkifyouonlystartwithasmallsampleofDNA?ProteinSynthesisWhatistheprocessoftranscription?Wheredoesitoccurandwhatenzymeisnecessary?Howistranscriptioninprokaryotesandeukaryotesdifferent?HowisthemRNAcopied?Whatisthedifferencebetweenthecodingandtemplatestrand?WhichonedoestheRNApolymerasebindto?

WhatispremRNA?Whyisitabitofahassleineukaryotes?Whatisthedifferencebetweenanintronandanexonandwhatistheenzymecalledthatcutsouttheunwantedportions?

HowelseismRNAprocessedbeforeitleavesthenucleus?IftheDNAisTACCCACACTTTmRNA_______________________________AminoAcids_______________________________Whatistranslation?TypesofMutationsNonsenseMissenseSilentDeletion/Insertion/Frameshift

GeneExpressioninProkaryotesOperons Inducible-Therepressorproteinthatismadebytheregulatorygeneisintheoperator.TheRNApolymerasecannotpassandthegenesarenotcodedfor.If

asubstanceistherethatneedstogetbrokendown(ex-lactosesothebacteriacangetthemuchneededglucose),themoleculewillfitintotherepressorproteinandalteritallostericallyandultimatelyremoveit,allowingtheRNApolymerasetotranscribethemRNAandcodeforthegenetobreakdownthegivenmolecule.

Inthisexamplealloftheenzymescodedforintheoperonwillallowlactosetobebrokendownandthebacteriacellcanusetheglucose.

Repressible-TherepressorproteinthatismadebytheregulatorygeneisNOTinthe

operator.TheRNApolymerasecanpassandthegenesarecodedfor.Thiswillcontinuebecausethecellismakingenzymesthathelpitbuildspecificmolecules(tryptophanissynthesizedinthetrpoperon).Oncethecellhasmadeenoughofthedesiredmolecule,theextrawillfitintotherepressorproteinandalteritallosterically.ThischangewillallowtherepressorproteintofitintotheoperatorandtheRNApolymerasewillnolongerbeabletotranscribethemRNAandcodeforthosespecificenzymes.

TherepressorproteinisNOTintheoperatorsotheRNApolymerasecantranscribethegenes.Onceenoughofasubstance(trp)ispresent,therepressorproteinisalteredsoitFITSintotheoperatorandblocksthetranscription.

GeneExpressioninEukaryotesHowisDNAcondensed?Howdoesgeneregulationleadtodifferentiation?HowdomethylationandacetylationaffectthecondensationofDNA?Whathappenswhenthecelldoesnotneedtheextraproteins/enzymesithas?Namethetwostepsthatarenecessary.