问题标题：
求有氧呼吸的英语定义.
问题描述：
求有氧呼吸的英语定义.
何启明回答：
Aerobicrespirationrequiresoxygeninordertogenerateenergy(ATP).Althoughcarbohydrates,fats,andproteinscanallbeprocessedandconsumedasreactant,itisthepreferredmethodofpyruvatebreakdowninglycolysisandrequiresthatpyruvateenterthemitochondrioninordertobefullyoxidizedbytheKrebscycle.TheproductofthisprocessisenergyintheformofATP(Adenosinetriphosphate),bysubstrate-levelphosphorylation,NADHandFADH2
Simplifiedreaction:2C3H6O3ΔG=-2880kJpermoleofC6H12O6
ThenegativeΔGindicatesthatthereactioncanhappenspontaneously
ThereducingpotentialofNADHandFADH2isconvertedtomoreATPthroughanelectrontransportchainwithoxygenasthe"terminalelectronacceptor".MostoftheATPproducedbyaerobiccellularrespirationismadebyoxidativephosphorylation.Thisworksbytheenergyreleasedintheconsumptionofpyruvatebeingusedtocreateachemiosmoticpotentialbypumpingprotonsacrossamembrane.ThispotentialisthenusedtodriveATPsynthaseandproduceATPfromADP.Biologytextbooksoftenstatethat38ATPmoleculescanbemadeperoxidisedglucosemoleculeduringcellularrespiration(2fromglycolysis,2fromtheKrebscycle,andabout34fromtheelectrontransportsystem).However,thismaximumyieldisneverquitereachedduetolosses(leakymembranes)aswellasthecostofmovingpyruvateandADPintothemitochondrialmatrixandcurrentestimatesrangearound29to30ATPperglucose.
Aerobicmetabolismis19timesmoreefficientthananaerobicmetabolism(whichyields2molATPper1molglucose).TheysharetheinitialpathwayofglycolysisbutaerobicmetabolismcontinueswiththeKrebscycleandoxidativephosphorylation.Thepostglycolyticreactionstakeplaceinthemitochondriaineukaryoticcells,andinthecytoplasminprokaryoticcells.
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