生物化学英文版习题生物化学英文版习题生物化学英文版习题FuelMetabolismPART1:StructureandFunctionofProteinDirections:Eachofthenumbereditemsorincompletestatementsinthissectionisfollowedbyanswersorbycompletionsofthestatement.Selecttheoneletteredanswerorcompletionthatisbestineachcase.Questions9and10Usethestructuretoanswerquestions9and10：Asp-Ala-Ser-Glu-Val-Arg9.TheC-terminalaminoacidofthehexapeptideshownis(A)alanine(B)asparagine(C)aspartate(D)arginine10.AtphysiologicpH(7.4),thishexapeptidewillcontainanetchargeof(A)-2(B)-1(C)0(D)+1(E)+211.Whichoneofthefollowingtypesofbondsiscovalent?(A)Hydrophobic(B)Hydrogen(C)Disulfide(D)Electrostatic13.Whichoneofthefollowingconditionscauseshemoglobintoreleaseoxygenmorereadily?(A)Metabolicalkalosis(B)Increasedproductionof2,3-bisphosphoglycerate(BPG)(C)Hyperventilation,leadingtodecreasedlevelsofCO2intheblood(D)Replacementoftheβsubunitswithγsubunits14.Productionofwhichofthefollowingproreinswouldbemostdirectlyaffectedinscurvy?(A)Myoglobin(B)Collagen(C)Insulin(D)Hemoglobin15.Theactivesiteofanenzyme(A)isformedonlyafteradditionofaspecificsubstrate(B)isdirectlyinvolvedinbindingofallostericinhibitors(C)residesinafewadjacentaminoacidresiduesintheprimarysequenceofthepolypeptidechain(D)bindscompetitiveinhibitors16.AnenzymecatalyzingthereactionE+S=ES→E+Pwasmixedwith4mMsubstrate.Theinitialrateofproductformationwas25%ofVm.TheKmfortheenzymeis(A)2mM(B)4mM(C)9mM(D)12mM(E)25mM17.Thevelocity(v)ofanenzyme-catalyzedreaction(A)decreasesasthesubstrateconcentrationincreases(B)islowestwhentheenzymeissaturatedwithsubstrate(C)isrelatedtothesubstrateconcentrationatlhVm(D)isindependentofthepHofthesolutionQuestions18and19Refertothefollowingreactionwhenansweringquestions18and19.Fumarate+H20↔malatefumarase18.Fumarasecatalyzestheconversionoffumaratetomalate.IthasaKmof5μMforfumarateandaVmaxof50μmol/min/mgofproteinwhenmeasuredinthedirectionofmalateformation.Theconcentrationoffumaraterequiredtogiveavelocityof25μmol/min/mgproteinis(A)2μM(B)5μM(