Glycolysis Overview of cellular respiration 4 metabolic stages –Anaerobic respiration 1. Glycolysis –respiration without O 2 –in cytosol –Aerobic respiration.

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<p>Glycolysis</p> <p>GlycolysisOverview of cellular respiration4 metabolic stagesAnaerobic respiration1. Glycolysisrespiration without O2in cytosolAerobic respirationrespiration using O2in mitochondria2. Pyruvate oxidation3. Krebs cycle4. Electron transport chain</p> <p>C6H12O66O2ATP6H2O6CO2+++(+ heat)2Glycolysis glucose pyruvate2x6C3CBreaking down glucose glyco lysis (splitting sugar)</p> <p>ancientwhere energy transfer first evolvedtransfer energy from organic molecules to ATPstill is starting point for ALL cellular respirationbut its inefficient generate only 2 ATP for every 1 glucoseoccurs in cytosol3Why does it make sense that this happens in the cytosol?Who evolved first?10 reactionsconvert glucose (6C) to 2 pyruvate (3C) produces: 4 ATP &amp; 2 NADHconsumes:2 ATPnet yield: 2 ATP &amp; 2 NADHglucoseC-C-C-C-C-Cfructose-1,6bPP-C-C-C-C-C-C-PDHAPP-C-C-C G3PC-C-C-PpyruvateC-C-COverviewDHAP = dihydroxyacetone phosphateG3P = glyceraldehyde-3-phosphateATP2ADP2</p> <p>ATP4ADP4NAD+22Pienzymeenzymeenzymeenzymeenzymeenzymeenzymeenzyme2Pi2H2</p> <p>41st ATP used is like a match to light a fire initiation energy / activation energy.</p> <p>Destabilizes glucose enough to split it in two</p> <p>Glycolysis summary endergonicinvest some ATPexergonicharvest a little ATP &amp; a little NADH</p> <p>net yield2 ATP2 NADH4 ATPENERGY INVESTMENTENERGY PAYOFF G3PC-C-C-PNET YIELD-2 ATP5Glucose is a stable molecule it needs an activation energy to break it apart.phosphorylate it = Pi comes from ATP.make NADH &amp; put it in the bank for later.</p> <p>Pi364,5ADPNAD+GlucosehexokinasephosphoglucoseisomerasephosphofructokinaseGlyceraldehyde 3-phosphate (G3P)DihydroxyacetonephosphateGlucose 6-phosphateFructose 6-phosphateFructose 1,6-bisphosphateisomeraseglyceraldehyde3-phosphatedehydrogenasealdolase1,3-Bisphosphoglycerate(BPG)1,3-Bisphosphoglycerate(BPG)12ATPADPATPNADHNAD+NADHPiCH2COCH2OHPOCH2OPOCHOHCCH2OPOCHOHCH2OPOCH2OP OPOCH2HCH2OHOCH2POOCH2OHPO1st half of glycolysis (5 reactions)Glucose primingget glucose ready to splitphosphorylate glucose (hexokinase) molecular rearrangementsplit destabilized glucose (1 DHAP, 1 G3P)6</p> <p>2nd half of glycolysis (5 reactions)</p> <p>Payola!Finally some ATP!</p> <p>78H2O910ADPATP3-Phosphoglycerate(3PG)3-Phosphoglycerate(3PG)2-Phosphoglycerate(2PG)2-Phosphoglycerate(2PG)Phosphoenolpyruvate(PEP)Phosphoenolpyruvate(PEP)PyruvatePyruvatephosphoglyceratekinasephosphoglycero-mutaseenolasepyruvate kinaseADPATPADPATPADPATPH2OCH2OHCH3CH2O-OCPHCHOHO-O-O-CCCCCCPPOOOOOOCH2NAD+NADHNAD+NADHEnergy Harvest G3PC-C-C-PPiPi6 DHAPP-C-C-CNADH productionG3P donates Hoxidizes the sugarreduces NAD+NAD+ NADHATP productionG3P pyruvatePEP sugar donates Psubstrate level phosphorylationADP ATP7Substrate-level Phosphorylation</p> <p>P is transferred from PEP to ADPkinase enzymeADP ATP</p> <p>I get it!The Pi camedirectly fromthe substrate!</p> <p>H2O910Phosphoenolpyruvate(PEP)Phosphoenolpyruvate(PEP)PyruvatePyruvateenolasepyruvate kinaseADPATPADPATPH2OCH3O-OCO-CCCPOOOCH2In the last steps of glycolysis, where did the P come from to make ATP?the sugar substrate (PEP)ATP</p> <p>78H2O910ADPATP3-Phosphoglycerate(3PG)3-Phosphoglycerate(3PG)2-Phosphoglycerate(2PG)2-Phosphoglycerate(2PG)Phosphoenolpyruvate(PEP)Phosphoenolpyruvate(PEP)PyruvatePyruvateADPATPADPATPADPATPH2ONAD+NADHNAD+NADHPiPi6Glycolysis</p> <p>glucose + 2ADP + 2Pi + 2 NAD+ 2 pyruvate + 2ATP + 2NADHBut cant stop there!Going to run out of NAD+without regenerating NAD+, energy production would stop!another molecule must accept H from NADHso NAD+ is freed up for another round</p> <p>PiNAD+G3P1,3-BPG1,3-BPGNADHNAD+NADHPiDHAPraw materials products9</p> <p>NADHpyruvateacetyl-CoAlactateethanolNAD+NAD+NADHNAD+NADHCO2acetaldehydeH2OKrebscycleO2lactic acidfermentationwith oxygenaerobic respirationwithout oxygenanaerobic respirationfermentationHow is NADH recycled to NAD+?Another molecule must accept H from NADH</p> <p>recycleNADHalcoholfermentation</p>

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