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Name____________________________________________________________ EnzymeStructureandFunctionThehighlycomplexorganizationoflivingsystemsrequiresconstantinputofenergyandtheexchangeofmacromolecules.1. Icandescribethepropertiesofenzymes
A. Labelthefollowinginthediagrambelow:substrate(reactants),enzyme,activesite,transition
state(enzymesubstratecomplex),product
B. DESCRIBEthestructureoftheenzyme- Isaprotein/polypeptidemadeupofaminoacids.Thespecificsequenceofaminoacids
determinesitsstructure.Primarylevelpeptidebondsaminoacidstogether,secondarystructurehashydrogenbondinteractionswithinthebackbonetertiarystructureinvolvessidechain(rgroup)interactions
- thergroupinteractionsformtheactivesitethatspecificallyinteractswithsubstrate
C. DESCRIBEthepropertiesoftheactivesitethatmustbepresentinorderforachemicalreactiontooccurwithasubstratethe shape and charge must be compatible with the substrate
2. IcanexplainhowThestructureandfunctionofenzymescontributetotheregulationofbiological
processes
A. EXPLAINtheimportanceoftheactivesiteinrelationtothesubstrate.- Theactivesitebindstothesubstrateandstabilizesthetransitionstate
B. IdentifythelineonthegraphthatshowsthereactionoccurringwiththepresenceofanenzymeANDlabelthelineonthegraphthatshowsareactionwithoutanenzyme
C. LabelthetransitionstateandDescribethedifferenceinthetransitionstatewithandwithoutanenzyme
Whentheenzymeispresent,theactivationenergyislowersothetransitionstateisreachedquicker….allowingthereactiontogofaster
D. Explainhowenzymesaffecttherateofbiologicalreactions- When the enzyme bonds to the substrate, the substrate is converted to an unstable intermediate called
transition state which the activation energy decreases and reaction rate increases
E. Inanexperimenttoshowtherateofanenzymecatalyzedreaction,explainwhydenaturedenzymescouldbeusedasanegativecontrolThenegativecontrolwillshowthatthechangesobservedintheexperimentresultfromchangesinenzymefunction.
Name__________________________________________________________Unit3:EnvironmentalImpactsonEnzymes
3. ChangetothemolecularstructureofacomponentinanenzymaticsystemmayresultinachangeofthefunctionorefficiencyofthesystemA. Describewhathappenstoanenzymewhenitisdenatured- Protein structure is disrupted. The r group interactions in the tertiary structure change( hydrogen bonds,
van der waals forces, etc) changing the shape of the active site, eliminating the ability to catalyze reactions
B. PredictwhatwillhappentothereactionratewhentheenzymeisdenaturedandJustifyyourprediction
- Reaction rate would decrease because the shape of the active site would no longer fit with the substrate
C. Identifyenvironmentalconditionsthatwouldcauseanenzymetodenature- pHandtemperature,salinity
4. EnvironmentalpHcanaltertheefficiencyofenzymeactivityA. Usingthegraphbelow,IdentifytheoptimalpHandIdentifythepHlevelsatwhichtheenzyme
denatures
B. DescribehowachangeinthepHoftheenvironmentcanaltertheefficiencyoftheenzymeactivity
OptimumpH:8.8
pHleveldenaturingenzyme:
8.7 and 8.9
AchangeinthepHaltersthechargeintheRgroupschangingtheshapeoftheactivesitenotallowingsubstratetofit…Decreasestheefficiencyoftheenzyme
5. Designacontrolledexperimentthatcouldhaveproducedthedata(picktemperatureorpH)
A. Hypothesis:AchangeinpHwillchangethereactionrate(canuseif/thenstatement)Achangeintemperaturewillchangethereactionrate
B. Whatismeasured(productformedorsubstrateused)
C. Howisitmeasured(numberofbubblesproduced,titration-colorchangewithKMnO4)
D. Statetheindependentvariable–includeatleast3datapoints pH- set at 4,6,8
temperature-25,25,45
E. Experimentaldesignsetup- Hydrogen peroxide as the substrate 10ml, catalase ( from yeast) as enzyme 1ml. specific temp or pH ( at
least 3 data points) length of reaction time,
F. Constants-initialconcentrationofsubstrate
G. Controlgroupboiledenzyme,noenzyme(Thenegativecontrolshelpconfirmthattheresultsoftheexperimentarerelatedtoenzymefunctionandnotsomeotherfactor.)
H. Experimentalgroups6. Competitiveandnoncompetitiveinhibitorscanhaveanimpactonenzymeactivity
A. DescribetheimpactinhibitorshaveonreactionratesSlowdownreactionrate
B. IdentifythereactionascompetitiveornoncompetitiveC. Underneatheachreaction,Explainwhythatinhibitorchangesenzymeactivity______Competitive_________________________ ______________noncompetitive_____________________Competitiveinhibitorcompeteswiththe noncompetitiveinhibitorbindsatlocationSubstratefortheActivesite.When awayfromactivesite(allostericsite)Competitiveinhibitorinactivesite, changingshapeofactivesitesosubstratenoSubstrateunabletoenterandreactionrate longerfitsactivesitedecreasesD. Describehowcompetitiveinhibitioncanbeovercome
Increasetheamountofsubstratepresent
E. Explainwhycompetitiveinhibitioncanbeovercome
Thecompetitiveinhibitorandsubstratecompetefortheactivesitesoincreasingtheamountofsubstratecanincreasethechancethatthesubstrategetstheactivesite
F. Explainwhynoncompetitiveinhibitioncannotbeovercomebytheadditionofmoresubstrate- Bindstotheallostericsite(siteawayfromtheactivesite)causingtheenzymesactivesiteto
changeshapeG. Compareandcontrastirreversibleandreversibleinhibitorsintermsofthebondingwiththe
enzymeWhentheenzymedenaturestheproteinstructureischangedchangingtheshapeoftheactivesite.IFitisreversible,theenzymewillregainthecorrectsecondaryandtertiarystructureallowingtheenzymetoregainactivity.
- Ifnoncompetitiveinhibitoriscovalentlybonded,theenzymewillbepermanentlybedenatured.--ifreversible,thebond/interactionwouldbenoncovalentbond(hydrogen,hydrophobicinteractions,etc)
7. Defineanallostericenzyme,statetheimportanceofanallostericenzymeandidentifytheactivesiteandregulatoryregionontheenzyme
A. Defineallostericenzyme-containssiteawayfromactivesitethatisregulatoryregionB. Importance-controlcatalyticactivityC. Labeltheenzyme,activesiteandregulatoryregionD. Explaintheimportanceofaregulatorymoleculeinanallostericenzyme
Wheninregulatoryregion(allostericsite)preventstheenzymefromcatalyzingthereactionconservingenergy/resources
E. Identifythepartsofametabolic-enzymecatalyzedpathway:labeltheallostericsite,activesite,substrate,product
F. DescribehowandexplaintheimportanceoftheproductactingasaninhibitorHow:_bindstotheallostericsite(regulatoryregion)changingtheshapeoftheactivesiteImportance:actsasafeedbackmechanismpreventssubstratefromenteringactivesite,controllingtheenzymeactivity.ifhaveenoughproduct,wanttoconserveresourcesanstopproductionofmoreproduct.
8. Therelativeconcentrationsofsubstratesandproductsdeterminehowefficientlyanenzymatic
reactionproceeds.
A. Describewhathappenstorateofreactionassubstrateconcentrationincreases- Increases then levels off
B. Explainwhythereactionratechangesassubstrateincreases
- Rate increases due to the enzymes acting on more substrates… reaction rate will slow because the ratio of product to substrate increases
C. Determinetherateofreactionbasedona graph
10-0/60-0=.17Ifaskedrateofchangefrom0-30secondsthen9-0/30-0=.39. EnvironmentalpHcanalter
theefficiencyofenzymeactivity
A. Describewhathappenstothereactionrateforthethermophilicbacteriaasthetemperatureincreasesfrom40-75.ANDEXPLAINwhythereactionratechanges
RateofreactionincreasesbecauseHigherenvironmentaltemperaturesincreasethespeedofmovementofmoleculesinasolution,increasingthefrequencyofcollisionsbetweenenzymesandsubstrates
B. Describewhathappenstothereactionrateforthethermophilicbacteriaasthetemperatureincreasesfrom75-90.ANDEXPLAINwhythereactionratechangesRate of reaction decreases because the enzyme denatures which disrupts the bonding and changes the shape of the active site preventing the substrate from entering the active site
Name__________________________________________________________ EnergyandPhotosynthesis1. Alllivingsystemsrequireconstantinputofenergy.
A. DescribethefirstlawofthermodynamicsEnergycannotbecreatedordestroyed,canonlychangedfromoneformtoanother
B. Explainhowthefirstlawofthermodynamicsisinvolvedwiththeprocessesoflivingorganisms(startingwithlightenergy)Photosynthesisconvertslightenergyintochemicalenergy.CellularrespirationconvertschemicalenergytousableenergyintheformofATP.Becausenot100%efficient,someenergylosttoenvironmentasheat.
C. ExplainwhathappenstosomeoftheenergyasitisconvertedfromoneformtoanotherBecausemetabolicprocessesnot100%efficient,someenergylosttoenvironmentasheat.
D. EXPLAINwhyEnergyinputmustexceedenergylosstomaintainorderandtopowercellularprocessesANDEXPLAINhowthisisachieved
Thetransferofenergyisnot100%efficientsoenergyislosttotheenvironmentasheat.Ifmoreenergyisrequiredformetabolicprocessesthatcanbesupplied,therewouldn’tbeenoughenergytosupportlifeanditwouldresultindeath.Photosynthesisconvertssunenergytosugar.Theremustbemoreenergyatproducerlevelthanhigherinthefoodchain.2. Cellularprocessesthatreleaseenergymaybecoupledwithcellularprocessesthatrequireenergy
A. DescribeATPhydrolysisandEXPLAINwhyATPhydrolysisisneededATPhydrolysis(exergonicreaction)breaksthebondbetweenthe2ndand3rdphosphatereleasingtheenergy.ATPhydrolysisiscoupled(linked)withanendergonicreactionsinceTheenergythatisreleasedfromthebreakdownofATPisusedtopowerendergonicreactions
B. WhichgraphwouldrepresentATPhydrolysisandJUSTIFYyouranswerGraphA GraphB
GraphBwouldbeATPhydrolysissinceitisanexergonicreaction.Theproductislowerthanthereactantsoenergywasreleased.TheenergyreleasedingraphB(ATPhydrolysis)willbeusedtopowergraphA(endergonicreaction)
C. EXPLAINwhyATPhydrolysisisoftencoupledwithotherreactionsandSTATEareactionthatwouldbecoupledwithATP
EndergonicreactionsrequireenergyandtheenergythatisreleasedfromATPhydrolysis(exergonicreaction)willbeusedtopowertheendergonicreactionssuchasproteinsynthesisandthesodium/potassiumpump
3. OrganismscaptureandstoreenergyforuseinbiologicalprocessesA. DESCRIBEhowphotosynthesisisinvolvedincapturingenergy
Chlorophylls(foundinbothphotosystemIIandI)andaccessorypigmentsabsorbthesunsenergyandboostelectronstoahigherenergylevelandthroughprocessofphotosynthesistheenergyisstoredinsugar
B. Explainthedependenceoforganismsontheprocessofphotosynthesis- Organisms that are unable to convert suns energy to chemical energy, rely on photosynthesis to do the
process. The organisms have to then consume the photosynthetic organism to obtain the stored energy
C. DescribetherelationshipbetweencellularrespirationandPhotosynthesis
PhotosynthesisconvertssolarenergyintochemicalenergyandcellularrespirationconvertsthechemicalenergyintotheusableATPenergy
4. Thelight-dependentreactionsofphotosynthesisineukaryotesinvolveaseriesofcoordinatedreactionpathwaysA. Describethestructureofthechloroplastandstatewherethelightdependentreactionandthe
Calvincycletakeplace- The chloroplast has a double membrane on the outside with thylakoids stacked on the inside which
compartmentalize the organelle. The light dependent reaction occurs in the thylakoid membranes and the calvin cycle occurs in the stroma.
B. Explaintheimportanceofthelightreaction
ProducesATPandNADPHwhichisusedtopowerthecalvincycle
C. Describethestructureofthephotosystemsthatareusedinthelightdependent
Containchlorophyllandaccessorypigmentsfoundinthethylakoidmembrane
D. DescribetheimportanceofpigmentssuchaschlorophyllsandaccessorypigmentsandEXPLAINwhyitisbeneficialtoaplanttohavealltypesnotjustone
Pigmentsareabletoabsorbthephotonsoflightfromthesunandboostelectronstoahigherenergystate.Differentpigmentsabsorbdifferentwavelengthsoflightallowingmorephotonsoflighttobeabsorbedmakingitmoreefficient
E. Explainhowchlorophyllisusedinthelightreaction
Absorbphotonsoflighttoboostelectronstoahigherenergystate
F. Describetheinvolvementofwaterinthelightreaction
PhotolysisoccurringsplittingwatersoelectronscanbeusedtoreplacetheelectronslosttoNADPH
G. Describehowthehighenergyelectronsareusedintheelectrontransportchain
Thehighenergyelectronsprovideenergytothetransportproteinsimbeddedinthethylakoidmembrane.Theenergyprovidedtothetransportproteinsallowstheproteinstoactivelytransporthydrogensintothethylakoidspace(lumen)
H. ExplaintheimportanceofthylakoidmembraneintheproductiononATP- Creates compartmentalization allowing a proton gradient to form. This will allow H+ to move back through
creating enough energy to phosphorylate ADP to form ADP
I. PredictwhattheoutcomeofthelightreactionwouldbeifaprotongradientcouldnotbeestablishedandJUSTIFYyourprediction
LessATPwouldbesynthesizedbecausetheprotongradientwouldnotbepresenttopowerATPsynthasetobondinorganicphosphatetoADP.
J. Describetheprocessofcarbonfixationthatoccursduringthecalvincycle
Atmospheric carbon dioxide gets incorporated into an organic molecules using ATP and NADPH from the light reaction as an energy source
K. Explaintheimportanceofthecalvincycle
The 3Csugar contains the chemical energy that be used in cellular respiration to produce usable energy ATP
5. MeasuretherateofphotosynthesisA. Identifytwowaystomeasuretherateofphotosynthesis
1. ProductionofO22. ConsumptionpfCO2
B. DESCRIBEwhatwouldhappentotherateofphotosynthesisforeachofthefollowing:- IncreaseinCO2-increaserateofphotosynthesis
- Decreaseinlight-decreaserateofphotosynthesis
- Changeincoloroflight-greenlightwoulddecreasephotosynthesiswhileredandbluewouldincreasephotosynthesis
C. Thefloatingleafdisklab-quickrefresher.Aholepunchwasusedtopunch10holesinaleaf.Theleafholepuncheswerethenplacedinasyringethatcontainedsodiumbicarbonate.Whenasuctionwascreated(yourfingerovertheopeningandpullingontheplunger),thegasesinthespacesoftheleafwereremovedandreplacedwithsodiumbicarbonatecausingthediskstosink.Thediskswerethenplacedinacupofsodiumbicarbonateanddifferentconditions(amountoflight)wereappliedtothecups.- Whatismeasured-rateofphotosynthesis
- Howisitmeasured-indirectlybyusingtheleafdiskproceduretomeasureoxygenproduction
- Theindependentvariable- Light intensity
- Constants- Typeofspinach,sizeofleafdisks,numberofdisks,amountofsodiumbicarbonate
- Expecteddata
- Aslightintensityincreases,rateofphotosynthesisincreases
- Controlgroup- Cupwithoutlight
- hypothesis- as light intensity increases, rate of photosynthesis increases. Disks will float faster.
Name_______________________________________________________________ Unit3:CellularRespirationReview1. Icandescribetheoverallprocessofcellularrespiration
A. ExplainthepurposeofCellularrespiration
- Convert chemical energy into usable energy for metabolic reactions to occur
B. LabelthepartsofthemitochondriaandIdentifywhereeachstepofcellularrespirationoccurs
C. Describeoxidationandreductionandgiveanexampleofeachincellularrespiration- Giving up electrons becoming more positive- glucose is oxidized - Gaining electrons becoming more negative- oxygen is reduced as it accepts the electrons at the end of
the electron transport chain
D. Statetheprocessthatiscommontoalllivingorganisms(prokaryotesandEukaryotes)andEXPLAINwhyitisabletooccurinalllivingorganisms
- Glycolysis occurs in all living organisms since it occurs in the cytosol and doesn’t require oxygen2. Icandescribehowglycolysisisusedincellularrespirationandexplainitsimportance
A. DescribetheoverallprocessofglycolysisandIdentifywhereglycolysisoccurs- Breakglucosedownintotwo3-carbonmolecules- Occursinthecytosol(cytoplasm)
B. Explainthepurposeofglycolysisandstatewhatisformedattheendofglycolysis
Oxidizingglucosereleasingenergyformingpyruvate,producingATPandNADPH.
C. ExplainwhyglycolysisisabletooccurinbothprokaryotesandeukaryotesAlllivingorganismshavecytosolwhereglycolysisoccurs
3. IcandescribetheKrebscycle(citricacid)explainitsimportance
A. IdentifythestartingmoleculeandstatetheprocessthatproduceditAcetylCoA–derivedfrompyruvate.GlycolysisproducespyruvatewhichismodifiedtoAcetylCoAtoenterthekrebscycle
B. ExplainwhycarbondioxideisproducedduringtheKrebscycleOxidationoccursandCO2isreleasedfromintermediatesascarbonsareremovedfromthemolecules
C. IdentifythecoenzymesthatreceivetheelectronsfromthecontinuedoxidationthatoccursduringtheKrebscycle
- NADH and FADH2
4. IcandescribehowTheelectrontransportchaintransfersenergyfromelectronsinaseriesofcoupledreactionsthatestablishanelectrochemicalgradientacrossmembranesANDEXPLAINtheimportance
A. Drawadiagramofoxidativephosphorylationthatisoccurringinthemitochondria
B. Explainwhyhighenergyelectronsareneededandstatethesource(s)ofthehighenergyelectrons- they provide energy to the the proteins in the electron transport chain to actively transport H+ from the
matrix to the intermembrane space forming a proton gradient ( or electrochemical gradient)
C. ExplainwhyaprotongradientisneededforphosphorylationofATPbyATPsynthasetooccur- As the H+ ions move by facilitated diffusion back through ATP synthase, Provides power to ATP synthase
for the phosphorylation of ADP
D. Describehowcompartmentalizationallowsaprotongradienttobeachieved
- Allows the separation of the matrix from the intermembrane space to allow a buildup of H+ in the
intermembrane space
E. Describetheinvolvementoftheelectrontransportchainintheformationofaprotongradient- The high energy electrons provide the power to the Proteins in the ETC to actively transport the
hydrogens from the matrix to the intermembrane space
F. DescribetheprocessofphosphorylationandExplainhowATPsynthaseisinvolvedintheproductionofATP
- Phosphorylation is the bonding of a phosphate. In ATP production, an inorganic phosphate is bonded to ADP creating a high energy structure. When the hydrogens move back through they provide ATP synthase the power in needs to phosphorylate ADP to form ATP
G. ExplainwhyOxygenisneededintheprocessofoxidativephosphorylation
- It is the terminal (final) electron acceptor at the end of the electron transport chain. If oxygen is not present, oxidative phosphorylation would stop
H. Explainthebenefittoendothermsforuncoupling(separating)theelectrontransportfromoxidativephosphorylation
TheuncouplingoftheETCgeneratesheatwhichallowsendothermstoregulateinternalbodytemperature5. Icanexplainwhatoccursintheabsenceofoxygentoallowforcellularrespirationtostillcontinue
A. Identifytheprocessthatiscommontofermentationandaerobicrespirationglycolysis
B. DescribetheprocessofFermentationandSTATEwhatisproducedinfermentationPyruvateisconvertedtolacticacidoralcoholandCO2andconvertsNADHtoNAD+.BydoingfermentationitallowsglycolysistooccurwithoutoxygenbyreplenishingNAD+soglucosecanbeoxidized…whichcausesNAD+tobereducedtoNADH.
C. ExplaintheimportanceofFermentation- Replenish NAD+ that is needed in glycolysis. NAD+ is an electron acceptor for oxidations that occur in
glycolysis allowing glycolysis to continue.
D. Explainwhylacticacidbuildsupinthemusclewhenoxygenisinshortsupply- The krebs cycle and oxidative phosphorylation stop and fermentation occurs which produces lactic acid.
CELLULARRESPIRATIONLAB
ICAN…
1. Explainthedifferenceinrespirationratebetweengerminatingandnon-germinatingseeds
Germinating seed have cells actively dividing so the respiration rate will be higher since the actively dividing cells require more energy
2. Determinetherateofchangeatvarioustemperaturesandexplainthedifferenceintherateofchangeforthedifferenttemperatures
A. Rateofchangeforgerminatingat22oC
.07
B. Rateofchangeforgerminatingat12oC
.04
C. Explaintherelationshipbetweenmetabolismandoxygen
AsmetabolismincreasesoxygenincreasessincemoreATPisneedsocellularrespirationmustincrease
3. ComparehowtherateofrespirationwouldchangeifmammalswereusedA. Wouldtherespirationrateinmammalsincreaseordecreaseincoldtemperaturesincrease
explainyouranswermustworkmusclesmoretogenerateheattomaintainbodytemperatureB. Wouldtherespirationrateinmammalsincreaseordecreaseinwarmtemperaturesdecrease
explainyouranswerdon’thavetoworkmusclesasmuchtomaintainbodytemperature
4. Explainthedifferencebetweenectothermsandendothermsatdifferenttemperatures
-Endothermsneedtoregulatetheirowninternalbodytemperatureandgenerateownheat
-ectothermsaredependentonexternalsources(environment)forbodyheat