iPad HebaSalma Adel & Heba Al-hyasat

iPad HebaSalma Adel & Heba Al-Hyasat

iPad HebaNafez Abutarboush

iPad Heba3

Metabolism:Sumofallbiochemicalreactionsinlivingorganisms(anabolismorcatabolism)(buildinguporbreakingdownmaterials)Bioenergetics:isthestudyofenergytransformationincellsfromthethermodynamicpointofview(potentialenergynotkineticenergywithinmater)Energyisthelife.So,manyprocessesinourbodyneedenergy:Mechanical,Activetransport,Biosynthesis,Heattypesofenergyare:1-Kineticenergy:theenergyduringmotionwhichdealswithmovement(thatwestudiedinlastsemesters)2-potentialenergy:energystoredwithinmaterialsthatcanbeconvertedtokineticenergyifneeded.KEEPinmindthatfoodisanexampleofpotentialenergy(whichisourcourse).Candeterminewhetherthereactionoccursornot(accordingtofavorabilitywe’lldiscussinthissheet)RelationbetweenEnergyandstability(Energyhasinverserelationshipwithstability)Highenergy(eitherpotentialorkineticenergy)materialindicateslowstabilityMainconceptorcausesforchemicalreactionistoachievemorestablesituation.GibbsEquation

Foranydelta=final-initial(Differencebetweenthepotentialenergyofproductandreactant)#Drsaidthatweshouldknowthedifferencebetweenenthalpychange(ΔH)andentropychange(ΔS).

Enthalpychange(ΔH):measurethebondenergyinbetweendifferentatomsanddifferentmoleculesinmaterialsEntropychange(ΔS):measurethedisorderbetweenthedifferentmolecules(closeorfarthertoeachother,theycangorandomly,etc…)fornaturesystemincreaseintime

🌸 ΔGisnegative,thereisalossofenergy(productmorestablethanreactant)🌸 Reactiongoesspontaneously(favorable)🌸 Thereactionisexergonic.#itisn’tspontaneouslyasitstate,becauseitshouldgotoahighenergystate(transitionstate)andtheenergythatisneedediscalledactivationenergy.

🌸 ΔGispositive,thereisagainofenergy(reactantmorestablethanproduct)🌸 Reactiondoesnotgospontaneously(unfavorable)🌸 Thereactionissaidtobeendergonic.

*ΔGisnotaffectedbythemechanismofthereaction(presenceorabsenceofenzymes)*ΔGisnotaffectedbythepathwayofthereactionsonlycaresaboutinitialandfinalstates,sothatwecalleditstatefunction.(ΔGfromAtoBtoC=ΔGfromAtoC)

Forexample:combustionofglucoseoutsidethebodywillrelease(—680kcal/mol)Insidethebodyglucoseundergo10stepstobeoxidisebutalsoitwillrelease(—680kcal/mol)So,wewillrepeatthatΔGcaresONLYaboutinitialandfinalstates.Glucose+O2→CO2+H2OΔG=-680kcal/molInthecellGlucose→→→→→→→CO2+H2OΔG=-680kcal/mol#Standardfreeenergychange(∆Go)VSFreeenergychange(∆G)∆G=thefreeenergydifferenceofasystematanycondition(maybedifferentbecauseofchangingconcentrationortemperature,etc…)Determinethefavorabilityofreaction∆Go=thefreeenergydifferenceofasystematstandardconditions(25Co&1atmosphericpressure,1Mconcentrationofreactants&products,pH=7)ItisalwaysconstantOurbodyhavechangingconditionssuchastemperatures,concentrationandpressuresothesamereactionindifferentregionmayhavedifferent∆Gvalue,butthesame(∆Go)value

*∆Go=thefreeenergydifferenceofasystematstandardconditions*Risthegasconstant *Tistheabsolutetemperature(K) Inrepresentsthenaturallogarithm#KEEPinmindthat,ifthevalueof

Inotherwords,if[P]=[R]lnequalszero[P]>[R]lnhaspositivevalue[P]<[R]lnhasnegativevalue

ىلعأ تالعافتملا زیكرت ناك ، 4= ةیرایعملا فورظلا يف اتلد ةمیق ضرتفنل ، ةلداعملا ىلع ًادامتعا-1=5–4G=∆ نوناقلا بسح و 5- يواستب و ةبلاس متیراغوللا ةمیق يلاتلاب و جتاونلا نم ھنا جنتسن و

Anendergonicreactionunderstandardconditionscanbeexergonicunderphysiologicalconditions. Equilibrium Equilibrium:isthestateofbalancewhen2rates(rateofproductsconvertingtoreactants,andrateofreactantsconvertingtoproducts)areequal.But,thatdoesn’tmeanthatequilibriumisequallyofconcentrationtobothreactantandproduct.

=1thelnwillbezeroGreaterthan1lnwillbe+veLessthan1lnwillbe-ve

.... يبرعلاب مھحضوأ تیبح نیتمولعم1)HowdoestheconcentrationaffectΔG???

حر لوم2 لوم دحاو لدب تمدختسا ول سب يرولاك5 ينیطعتب اھرسكا امل لوم دحاو اھزیكرت ةدام ΔG ةمیق ىلع رثأتب زیكرتلا ةدایز يلاتلاب و يرولاك10 ينیطعت ریصت

2)DeltaGhasnothingtodoaboutreactionrate نم ىلعأ ىلوألا زیكرت ينعی( بالط 10 اھیف ةیناثلا و بلاط100 اھیف ىلوألا نیتفرغ ھیف ھنا لیخت ةیناثلا نم ىلعأ اھیف يج اتلد ىلوألا قوفلا انمالك بسح ؟ ينعی )ةیناثلا

بالط3 و ةیناثلا ةفرغلل ىلوألا ةفرغلا نم ةقیقد لك بالط3 لقتنی ثیحب بالطلل ةمظتنم ةكرح تلمع فالتخالا نم مغرلا ىلع ةقیقد لكب بالط3 يواسی و ھسفن مھعبتrate ينعی ( ىلوألل ةیناثلا نم ) اتلدلاب ریبكلا ratereactionaboutdotonothinghasGDelta ھنا فیك مھفنب كیھ و

Atequilibrium: ΔG=0(sincethedrivingforceofanyreactionatequilibriumiszero)substituteΔG=0weget;

whereKeqistheequilibriumconstant.So,onceweknowtheKeqforareactionwecantelltheratiobetweenproductsandreactantswhenthereactionreachesequilibrium.e.g.iftheKeq=100thatmeansatequilibrium[P]=100*[R]IfKeqishigh(>1000)thenweknowthatatequilibriumthereactionismostlycomposedofproductsandasmallproportionofreactants,thuswecansaythatthereactionisalmostcompleted.whilewhenKeqislow(

TheEffectOfChangingConditionsOnEquilibrium

Howtheequilibriumisgettingaffectedbydifferentfactors?Whatarethefactorsthataffectstheequilibrium?

Whenastress(anychangethatdisturbstheoriginalequilibrium)isappliedtoasystematequilibrium,theequilibriumshiftstorelievethestress.

1)EffectOfChangesInTemperature —>Thegoalbehindthatistoconsidertemperatureasoneofthereactantsoroneoftheproductsdependingonyourknowledgeofthisreactionifitisexothermicorendothermic—>Ifthereactionisexothermicthenheatisbeingreleasedduringthereactionandthusheatcontentisconsideredtobeapartoftheproducts,soincreasingTisthesameasincreasingproductsconcentrationthereforethereactionshiftstowardmakingmorereactants(⬆ T —> encouragingthebackwarddirection)—>Ifthereactionisendothermicthenheatisbeingconsumedduringthereactionandthusheatcontentisconsideredtobeapartofthereactants,soincreasingTisthesameasincreasingreactantsconcentrationthereforthereactionshiftstowardmakingmoreproducts(⬆ T —> encouraging the forward direction) Until we reach the equilibrium state So : endothermic/exothermicarefavoredbyincrease/decreaseintemperature,respectively

2)EffectOfChangesInConcentrationWhathappensifareactant/productiscontinuouslysupplied/removed?—>Ifyouhaveanequilibriumstate,andyouincreasethereactantsconcentration,thereactionwillgoforward,untilachievingabalancestate—>Ifyouhaveanequilibriumstate,andyouincreasetheproductsconcentration,thereactionwillgobackward,untilachievingabalancestate —>Metabolicreactionssometimestakeadvantageofthiseffect3)noeffectofacatalyst(enzyme)onequilibrium:itjusthelpsthereactiontoachieveequilibriumfaster,becausecatalystsplayonwhatisbetweenthereactantsandproducts,whilewhendiscussing🔺 G we are not concerned on what is in between the tow points, as 🔺 G represents the difference in free energy between products and reactants

EnergyMachineryInTheCell

—>90% ofthebody’senergy(ATP)ismadeinsidemitochondria(single:mitochondrion)therestofit(10%)ismademainlythroughglycolysisinthecytosol—>Thenumberofmitochondriaisgreatestineye,brain,heart,&muscle,wheretheneedforenergyisgreatest—>mitochondriaisfoundonlyineukaryoticcells—>accordingtotheevolutiontheoryamitochondrionisaprokaryotethatinvadesaneukaryoticcellinreciprocalrelationshiptogiveitenergy,whilethecellgivesthemitochondriathesupplyaccordingtothat,—>Thereasonwhytheyconsiderthis⬆ is that the mitochondria is different in every thing : it has an outer membrane, a convoluted inner membrane (cristae), a space between them, a matrix inside where all processes happen, reproduction happens by division (like the reproduction of bacteria) and not by mitosis, it has its own circular DNA which produces some of the proteins that are needed in the mitochondria (not all of them because it’s a small DNA, while other needed proteins are produced by nuclear DNA) Reproductionofmitochondria—>Reproduction of mitochondria is governed (determined) by the need of energy —>When needing more energy mitochondria will start replicating, this is why training and exercises are beneficial for the human body —>it creates more mitochondria so more energy sources inthepresenceofoxygen —>this is why athletes behave better in exercises than ordinary people, (they have more mitochondria, more oxygen supplies, more ATP) —>Maternalinheritance,mitochondriaarenormallyinheritedexclusivelyfromthemother;themitochondriainspermareusuallydestroyedbytheeggcellafterfertilizationsothepaternalgeneticmaterialonlygetstransmitted.

NuclearDNAhastwocopiespercell(exceptforspermandeggcells),onecopybeinginheritedfromthefatherandtheotherfromthemother.MitochondrialDNA,however,isstrictlyinheritedfromthemother.Duringcelldivisionthemitochondriasegregaterandomlybetweenthetwonewcells

رثاكتلا لالخ ماسقنالا نم ةجتانلا ایالخلا ىلع يواستلاب عزوتی ایردنوكوتیملا ددع طرش شمAsDNAiscopiedwhenmitochondriaproliferate,theycanaccumulaterandommutations,aphenomenoncalledheteroplasmy.—>IfamutationhappensinthenuclearDNA🧬 thatproducesaproteinthatisneededinsidethemitochondriathenthatmutationwillbealloverthebodybecausethewayofreplicationofnuclearDNAisthroughmitosiswhichwillrenewthemutationinalldaughtercells—>WhilethereisnoregulatedwaydistributesmitochondrialDNAbetweendaughtercellsmitochondriawhenmothercellsreplicate,somutatedmitochondriacanexistinonedaughtercellbutotherdaughtercellmighthavenormalmitochondria,Ifthismutationhappens inthefirstfetalstagesand:(forexample)thedaughtercellthathasamutatedmitochondrialDNAisdesignatedtoformthenervoussystem,andthesecondisdesignatedtomakethemuscletissue,mitochondrialdiseasewillaffectthenervoussystemwhilethemuscularsystemishealthy

StagesOfEnergyProductionStage1(Digestion):itincludesingestionoffood,degradation,absorptionthenallmoleculeswillbemovedtothebloodsoitcanreachallcells.*Carbohydratestoglucose&othersugars*Proteinstoaminoacids*TriacylglycerolstoglycerolplusfattyacidsStage2(Acetyl-coenzymeA)

Stage3:AcetylCoAenterstheKrepscycleseekingforenergyproductionanditproducesmoleculesthatcarryelectrons(NADHandFADH2).Stage4:electrontransferchain&oxidativephosphorylation

—>WhyATPistheenergycurrencyofthecell?NOTbecauseithas3phosphateorithashighenergyorthenegativechargesitcarries.Butbecauseithasanintermediateenergyvalue,socanbecoupledweneedamoleculewithanintermediateamountofenergy(ATP)soitcanbebrokendownandresynthesizedeasily(thesameamountofenergyreleasedfrombreakageofATPtoADPmustbesuppliedtoADPtosynthesisATPagain).ThismeansthatifweassumethatbreakingP—ObondinATPgives20kcal/mole,itmeansthatIneedareactioninthebodythatgives20kcal/molewhenitbreaksinordertousethisenergytoformATPagainandthisisnotactuallyfoundinthebody.Soweneedamoleculewithanintermediateenergyvaluethatsufficesmostreactionsinthebodybyusing1moleculeofATP(whenIneedmoreIcanuse2or3ATPs).TherearealsomanyreactionsthatgivethesameamountofenergythatATPproducessoitcancompensateATP.

ATPistheenergycurrencyofthecell,ithasatriphosphategroupandbreakingdowneachP-Obondgivesenergy

Whatdeterminestheamountofenergyabondstores—>istheatomsthatareinvolveddirectlyinthebond(phosphateandoxygenforexampleinATP)andthedistributionofatomsaroundthisbondwhichmakesstrainonthebondsoitchangestheenergyofthebond.

-7.3kcal/mole-3.4kcal/mole

ThereisnoplacewhereATPisstoredinthebody,energyisstoredasbondsin(carbohydrates,lipids,…)…Why??BecauseweconsumeahugeamountofATPeverydaythatequals90.6moles/dayTheamountofATPneededperday:

IfyouknowthatM.WofATP=551g/mole—>551(g/mole)*90.6(moles/day)=49,920gSo,youneed49,920gATP(approximately50,000gATP)!!!ThatmeansifyourbodystoreenergyasATPmoleculesyou’lladd50Kgtoyourweight,alsoyoursizeaftereatingwillbeincreasedandwhenyou’rehungryit’lldecrease(unreality)PathwaysWhydoweneedenergy?(1)theperformanceofmechanicalworkinmusclecontractionandcellularmovements.(2)theactivetransportofmoleculesandions(3)thesynthesisofmacromoleculesandotherbiomoleculesfromsimpleprecursors.

Sunisthemainsourceofenergy,itgivesenergytoplants(autotrophs)toproducetheirownfoodandthenanimals(heterotrophs)willfeedonplants,thenhumancaneatbothofthemtogethisfood.*Cellularmetabolism:thesumofthetotalbiochemicalactivitiesofallcells(anabolismandcatabolism).Mainlyforenergygeneration*Metabolismconsistsofenergy-yielding(exergonic)andenergy-requiring(endergonic)reactions.

PathwaysinourbodyPathwaysinthebodyaretreatedassinglereactionswithrespecttothermodynamicsandbioenergetics,SoifIknowthestartingmoleculeandtheendmolecule,Icanknowifthispathwayisexergonicorendergonic.1.Linearpathway:everymaterialconvertedtoanothermaterialuntilachieveproduct,andeachstepisdrivenbydifferentenzyme.2.cyclicpathway:eachstepcausesanotheroneandbytheendofpathway,firstmaterialisregenerated.Eachstepiscatalysedbydifferentenzymes.3.spiralpathway:everymaterialconvertedtoanothermaterialuntilachieveproducteachstepiscatalysedbysamesetofenzymes( و ، ماعلا طمنلاب رینیل ھبشت

تامیزنالا عوضوم وھ فالتخالا نكل

Allpathwaysinourbodyneedtounderstandeachothertoconserveenergyfromloosing,allostericenzymehelpsinthisprocess…How?Allostericenzyme:enzymethathavemultiplebindingsitesfordifferentmoleculesfromdifferentpathwaysandareas,thathelpsmoleculestocollaboratewitheachotherandconserveenergy.

ExergonicpathwaysBreakingdownallmoleculesso,releasingenergyComplexstructures—>simplestructuresProteins→aminoacidsStarch→nglucoseglucose+O2→CO2+H2OE.gMorespecifically:🌸 Hydrolysisreactions🌸 Decarboxylationreactions(releaseofCO2)pyruvate(C3)→acetyl-CoA(C2)+CO2🌸 OxidationwithO2Endergonicpathways….Howdoourcellsgetenergyforit?ByconceptofCoupling:couplethereactionthatconsumedenergywiththereactionthatreleasedenergy(thatnotverysmart),,,,completereadingtoknowthesmartestconceptonourbodyCouplingareactionconsumeenergytoaddcertainmaterialandotherreactionreleaseenergyandthatmaterial,too.

BestexampleonthatsmartestconceptisPhosphorylationtransferreaction

It’snotjustATPthatcanbeused,wecanalsouseanyothermoleculethatgivesenergyandpartofthismoleculeisneededinthereaction.ActivatedIntermediatesotherthanATP;UTPisusedforcombiningsugars,CTPinlipidsynthesis,andGTPinproteinsynthesis Eg2:RemmemberalwaysactylecoAprovidesenergybecauseitsconnectedwithcoenzymeAwhichhassulfhydrilgroup,becauseithasmodifiedcystine,breakingdownofthebondbetweensulfurandcarbonwillreleaseenergycomparabletoATPormoreNowallofyouknowtheacytlecolin(byhavingtheacetateandthecolin—>theacetatefromacytlecoA),theenergyneededforcombiningacetate+cholinisreleasedfrombreakingthebondinacytlecoA

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Step2:Glucoseisalwaysconvertedtoglucose-6-phosphatethatneedenergy=3.3kcal/molSo,theATPcansupplythatreactionwith(material(phosphate)+energyneeded),soherewewillhavesomeexcessenergy4kcal/mole(thisexcessenergycanbeusedduringthepathwayorinotherreactions).Step4getsitsenergybyplayingwiththeconcentrations.AsΔGDependsonSubstrateandProductConcentration.Theoriginal(products/reactants)ratiois6/94soΔG=+1.65kcal/molbutifwecanwithdrawsomeoftheproductsoutthentheratiowillbecome3/94andΔG=-0.4kcal/molsothereactionwillbecomeexergonic.

Somepathwaysgeneratehighenergyintermediatelikeinstep5whereUDP-Glucoseisproducedwhichmeansthatitsseparationwillsupplytheenergyneededforthepathway.Sohereinstep7,separationofUDPfromglucosegivestheenergytoattachtheglucosetoglycogen.