Presentation on theme: "Cellular Respiration Glycolysis Krebs cycle Electron transport."— Presentation transcript:
1Cellular RespirationGlycolysisKrebs cycleElectron transport
2Learning checkThis figure represents an overview of the different processes of cellular respiration.Which of the following correctly identifies the different processes?1. Glycolysis; 2. Electron transport chain; 3. Krebs cycle1. Glycolysis; 2. Krebs cycle; 3. Electron transport chain1. Krebs cycle; 2. Electron transport chain; 3. Glycolysis1. Electron transport chain; 2. Glycolysis; 3. Krebs cycle
3What would happen to the flow of electrons if oxygen were not present? The flow of electrons would continue but at a slower rate.The flow would cease and ATP production would stop.The presence of oxygen would have no effect.
4Cyanide binds strongly with the last electron carrier in the chain. How would this affect the flow of electrons?The flow of electrons would continue but at a slower rate.The flow would cease and ATP production would stop.The presence of cyanide would have no effect.
6Cell Respiration Overview Glucose:Stores energy in the moleculeCell respiration:Breaks down the moleculesExtracts the contained energyTransfers electrons (from glucose)To hydrogen carriers (e.g., NADH)And to make ATPGiving off waste products (CO2 & H2O)1st stage:2nd & 3rd stage:CytoplasmMitochondria
71st stage:2nd stage:3rd stage:GlycolysisKrebs cycle (or citric acid)Electron transport
8Glycolysis, in the cytoplasm Series of steps (but 2 phases)1.Glucose2 pyruvic acid moleculesAs bonds in glucose are brokenElectrons (and H+ ions)NAD+2.NADHGlucoseIs oxidizedNAD+Is reducedNet output is 2 ATP for each glucose moleculeBut, most of the released energy carried by NADH
10Glycolysis, phase 1Some ATP is used to start the ‘breakdown’ of glucoseMitochondriaCytoplasmView Activity: Glycolysis
11Glycolysis, phase 2 High energy electrons are donated To NAD+ Forming NADH
12Glycolysis, phase 2And, phosphate groups are transferredATP is made
13In-between glycolysis & Krebs Just before (or as) they enter the mitochondriaPyruvic acid molecules are modifiedAnd CO2 is releasedThe altered molecule is acetic acid(…vinegar!)Acetic acid is attached to a carrier moleculeCalled coenzyme AAnd forms acetyl CoATo the mitochondrion
14Learning check 7 3 4 2 6 8 1 5 Name molecule Name of molecule Name the reactionName of moleculeWhat does the arrow refer to?Where does this take place?
15Krebs cycle, in the mitochondria Series of reactionsContinues to break down the sugarPresent as acetic acidCaptures more energyAs NADH & FADH2And more CO2 is releasedNet output is 2 ATP for each glucose moleculeBut again, most of the released energy carried by NADH
16Krebs (citric acid) cycle & energy production Waste:2 CO2Fuel:Acetic acid33Acceptor moleculeView Activity: The Citric Acid Cycle
17Electron Transport, in the mitochondria Most of the ATP is produced in the ETAnd, NADH & FADH donate their electrons to the ETAt the end of the chain of stepsO2 exerts a strong pull on electronsAnd combines electrons & H+ ions to form H2OThe ‘downhill’ flow of electrons powers an enzymeATP synthaseWhich produces ~ 34 ATP
18Electron Transport An array of molecules (…proteins) In the inner membrane of the mitochondrionView Activity: Electron Transport
19Electrons move from one member to the next The energy given up pumps H+ to inner spaceMatrixOxygen captures electronsHydrogens are added, water forms
20The buildup of H+ ions give up energy When they diffuse through a special proteinATP synthaseMatrixATP synthase captures their energyTo make ATP
21Learning check, name the numbered parts 15How many?1047111691423128161751318
22Learning checkOf the 3 stages of cell respiration, which produces the most ATP per glucose?In glycolysis, _______ is oxidized and _______ is reduced.The final electron acceptor of the electron transport chains in mitochondria is _______.
23Learning checkCells can harvest the most chemical energy from which of the following?An NADH moleculeA glucose moleculeSix carbon dioxide moleculesTwo pyruvic acid molecules