Define:  Glycolysis  Respiration  Chemiosmosis  Phosphorylation  Fermentation  ATP (draw and label)  Electrochemical gradient  FAD  FADH 2  NAD

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  • Define:GlycolysisRespirationChemiosmosisPhosphorylationFermentationATP (draw and label)Electrochemical gradientFAD FADH2NAD+ NADHWhat is the role of phosphofructokinase? How does it work?

    Explain glycolysis. Where does it occur? How does it work?

  • What is the chemical equation for cellular respiration?Remember: OILRIGIn the conversion of glucose and oxygen to CO2 and H2O, which molecule is reduced?Which is oxidized?What happens to the energy that is released in this redox reaction?NAD+ is called a(n) ________________.Its reduced form is _______.

  • What is 1 fact you remember from yesterdays sugar article?Why is glycolysis considered an ancient metabolic process?Where in the cell does glycolysis occur?What are the reactants and products of glycolysis?

  • Heres what!Summarize the main ideas in this articleWhat is the research about?So what?Why is the research being conducted?What is the importance of this work?What is the data showing?Now what?What are the next steps?What do scientists hope to accomplish in the future with this information?

  • Which has more energy available:ADP or ATP?NAD+ or NADH?FAD+ or FADH2?Where does the Citric Acid Cycle occur in the cell?What are the main products of the CAC?

  • What are 3 ways respiration can be measured?What is the purpose of using KOH (potassium hydroxide) in this lab?What are the Independent and Dependent Variables for Graph 5.1?

  • How is the proton gradient generated?

    What is its purpose?

    Describe how ATP synthase works.

  • Where are the proteins of the ETC located?Where does the ETC pump H+ ions into?In cellular respiration, how many ATP are generated through:Substrate-level phosphorylation?Oxidative phosphorylation?

  • In fermentation, how is NAD+ recycled?You eat a steak and salad. Which macromolecule cannot be broken down to make ATP?Think about the structure of a fat molecule. What feature of its structure makes it a better fuel than a carbohydrate (like glucose)?Explain where the fat goes when you lose weight.

  • In fermentation, how is NAD+ recycled?What is the function of the enzyme phosphofructokinase?You eat a steak and salad. Which macromolecule cannot be broken down to make ATP?Explain where the fat goes when you lose weight.

  • The summary equation of cellular respiration.The difference between fermentation and cellular respiration.The role of glycolysis in oxidizing glucose to two molecules of pyruvate.The process that brings pyruvate from the cytosol into the mitochondria and introduces it into the citric acid cycle.How the process of chemiosmosis utilizes the electrons from NADH and FADH2 to produce ATP.

  • E flows into ecosystem as Sunlight

    Autotrophs transform it into chemical EO2 released as byproduct

    Cells use some of chemical E in organic molecules to make ATP

    E leaves as heat

  • Complex organic moleculesSimpler waste products with less ESome E used to do work and dissipated as heatCatabolic Pathway

  • Respiration: exergonic (releases E)C6H12O6 + 6O2 6H2O + 6CO2 + ATP (+ heat)

    Photosynthesis: endergonic (requires E)6H2O + 6CO2 + Light C6H12O6 + 6O2

  • Xe- + Y X + Ye-

    Oxidation = lose e-Reduction = gain e-

    C6H12O6 + 6O2 6H2O + 6CO2 +


  • Energy is released as electrons fall from organic molecules to O2Broken down into steps:Food (Glucose) NADH ETC O2Coenzyme NAD+ = electron acceptorNAD+ picks up 2e- and 2H+ NADH (stores E)NADH carries electrons to the electron transport chain (ETC)ETC: transfers e- to O2 to make H2O ; releases energy

  • GlycolysisPyruvate Oxidation + Citric Acid Cycle (Krebs Cycle)Oxidative Phosphorylation (electron transport chain (ETC) & chemiosmosis)

  • Cellular Respiration

  • sugar splittingBelieved to be ancient (early prokaryotes - no O2 available)Occurs in cytosolPartially oxidizes glucose (6C) to 2 pyruvates (3C)Net gain: 2 ATP + 2NADHAlso makes 2H2ONo O2 required

  • Stage 1: Energy Investment StageCell uses ATP to phosphorylate compounds of glucose

    Stage 2: Energy Payoff StageTwo 3-C compounds oxidizedFor each glucose molecule:2 Net ATP produced by substrate-level phosphorylation2 molecules of NAD+ NADH

  • Generate small amount of ATPPhosphorylation: enzyme transfers a phosphate to other compounds

    ADP + Pi ATP

  • glucose2 pyruvate2 ATP2 NAD+2 NADH + 2H+(3-C)C3H6O3

  • Cellular Respiration

  • Citric Acid Cycle(matrix)ETC(inner membrane)

  • Pyruvate Acetyl CoA (used to make citrate)CO2 and NADH produced

  • Occurs in mitochondrial matrixAcetyl CoA Citrate releasedNet gain: 2 ATP, 6 NADH, 2 FADH2 (electron carrier)ATP produced by substrate-level phosphorylationCO2


  • Cellular Respiration

  • ELECTRON TRANSPORT CHAINOccurs in inner membrane of mitochondriaProduces 26-28 ATP by oxidative phosphorylation via chemiosmosisCHEMIOSMOSISH+ ions pumped across inner mitochondrial membraneH+ diffuse through ATP synthase (ADP ATP)

  • Collection of molecules embedded in inner membrane of mitochondriaTightly bound protein + non-protein componentsAlternate between reduced/oxidized states as accept/donate e-Does not make ATP directlyEase fall of e- from food to O22H+ + O2 H2O

  • Chemiosmosis = H+ gradient across membrane drives cellular workProton-motive force: use proton (H+) gradient to perform work

    ATP synthase: enzyme that makes ATPUse E from proton (H+) gradient flow of H+ back across membrane

  • e- passed down E levelsoxidative phosphorylationchemiosmosisATPETCO2 H2Oproton gradientproton motive forceH+redox reactionsATP synthaseusesuses Eofin whichto final e- acceptorgenerateswhich couplescalleddrivesthroughto produceH+ pumped from matrix to intermembrane space

  • Anaerobic Respiration: generate ATP using other electron acceptors besides O2Final e- acceptors: sulfate (SO4), nitrate, sulfur (produces H2S)Eg. Obligate anaerobes: cant survive in O2

    Facultative anaerobes: make ATP by aerobic respiration (with O2 present) or switch to fermentation (no O2 available)Eg. human muscle cells

  • FERMENTATIONKeep glycolysis going by regenerating NAD+Occurs in cytosolNo oxygen neededCreates ethanol [+ CO2] or lactate2 ATP (from glycolysis)

    RESPIRATIONRelease E from breakdown of food with O2Occurs in mitochondriaO2 required (final electron acceptor)Produces CO2, H2O and up to 32 ATP

    O2 presentWithout O2

  • ALCOHOL FERMENTATIONPyruvate Ethanol + CO2Ex. bacteria, yeastUsed in brewing, winemaking, bakingLACTIC ACID FERMENTATIONPyruvate LactateEx. fungi, bacteria, human muscle cellsUsed to make cheese, yogurt, acetone, methanolNote: Lactate build-up does NOT causes muscle fatigue and pain (old idea)

  • Carbohydrates, fats and proteins can ALL be used as fuel for cellular respirationMonomers enter glycolysis or citric acid cycle at different points

  • Allosteric enzyme that controls rate of glycolysis and citric acid cycleInhibited by ATP, citrateStimulated by AMPAMP+ P + P ATP

  • ENERGYglycolysis(cytosol)ethanol + CO2(yeast, some bacteria)anaerobic (without O2)aerobic cellular respiration(with O2)lactic acid(animals)ETCchemiosmosisoxidative phosphorylationcitric acid cyclemitochondriaFermentation(cytosol)

  • Electron Transport ChainChemiosmosis