Cellular Respiration. What Is ATP? Energy used by all Cells Adenosine Triphosphate Organic molecule containing high- energy Phosphate bonds Copyright.

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Cellular RespirationWhat Is ATP?Energy used by all CellsAdenosine TriphosphateOrganic molecule containing high-energy Phosphate bondsCopyright CmassengaleCopyright CmassengaleATP for energyATP powers cellular work- made in photosynthesis and cellular respirationA cell does three main kinds of work:Mechanical work, beating of cilia, contraction of muscle cells, and movement of chromosomes(produces heat)Transport work, pumping substances across membranes against the direction of spontaneous movementChemical work, driving endergonic reactions such as the synthesis of polymers from monomersHigh Energy Electrons and MoleculesElectron Carrier: a molecule that picks up the electron and uses this energy to break apart bonds.Examples of electron carriers: NADP and ATPNADP captures two electrons of H and becomes NADPH.ADP becomes ATP!!!How Do We Get Energy From ATP?By breaking the high- energy bonds between the last two phosphates in ATPCopyright CmassengaleCopyright Cmassengale*How Does ATP Work?So what?Energy is stored in these bonds.So?The breaking of the chemical bond releases the energyATP + H2O ADP + P + ENERGYATP is made in photosynthesis and respiration!!!ATP (adenosine triphosphate) is a a molecule that carries energy that cells can use.How Does ATP Work?The bonds between phosphate groups can be broken by hydrolysis which produces energy!!!ATP has 3 phosphate groups The bond to the third bond is easily broken. When the third bond is broken, energy is released. Becomes ADP no energy!!Chemical Structure of ATP3 PhosphatesRibose SugarAdenine BaseCopyright CmassengaleCopyright CmassengaleWhat Does ATP Do for You?It supplies YOU with ENERGY!Copyright CmassengaleHow Do We Get Energy From ATP?By breaking the high- energy bonds between the last two phosphates in ATPCopyright CmassengaleCopyright CmassengaleWhat is the Process Called?HYDROLYSIS (Adding H2O)H2OCopyright CmassengaleCopyright CmassengaleHow Does That Happen?An Enzyme!Copyright CmassengaleHow is ATP Re-Made?The reverse of the previous process occurs.Another Enzyme is used!ATP SynthaseCopyright CmassengaleCopyright CmassengaleThe ADP-ATP CycleATP-aseATP SynthaseCopyright CmassengaleCopyright CmassengaleWhen is ATP Made in the Body?During a Process called Cellular Respiration that takes place in both Plants & AnimalsCopyright CmassengaleCellular Respiration The process in which cells turn food into usable energy in the form of ATP. RELEASES CHEMICAL ENERGY FROM SUGARS AND OTHER CARBON-BASED MOLECULES TO MAKE ATP WHEN OXYGEN IS PRESENT!!!!NO OXYGEN FERMENTATION!!!!Cellular RespirationThe Purpose of Cellular RespirationIt is to make and break bonds to generate ATP and electrons.You end up with ATP, H ions and electrons.The electrons are sent to the Electron Transport Chain where they help to make ATP through ATP synthase.****Hydrogen ions are bonded with oxygen to make water which is used in photosynthesis.Cellular Respiration OverviewTransformation of chemical energy in food into chemical energy cells can use: ATPThese reactions proceed the same way in plants and animals. Process is called cellular respirationOverall Reaction:C6H12O6 + 6O2 6CO2 + 6H2OOverall Equation for Cellular Respiration 6CO2 + 6H20 + e- + 36-38ATPsC6H12O6 + 6O2YIELDSWhat are the Stages of Cellular Respiration?GlycolysisThe Krebs CycleThe Electron Transport ChainCopyright CmassengaleCopyright CmassengaleCellular Respiration Glycolysis Occurs before Cell. Resp.Krebs Cycle (Citric Acid Cycle)Electron Transport Chain (ETC)GlucoseGlycolysis Krebs cycle Electron transportFermentation (without oxygen)Alcohol or lactic acidOverall ReactionC6H12O6 + 6O2 6CO2 + 6H2O + 38 ATPOverall this is a three stage processGlycolysis: before cellular respirationOccurs in the cytoplasmGlucose is broken downKrebs CycleBreaks down pyruvate into CO2Occurs in mitochondrial matrixElectron Transport ChainATP is synthesized - Occurs in mito membraneFlowchartSection 9-2Glucose (C6H1206)+Oxygen (02)GlycolysisKrebs CycleElectron Transport ChainCarbon Dioxide(CO2)+Water(H2O)+ATPCellular RespirationWhere Does Cellular Respiration Take Place?It actually takes place in two parts of the cell:Glycolysis occurs in the CytoplasmKrebs Cycle & ETC Take place in the MitochondriaCopyright CmassengaleGlycolysisDefinition: The process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid, a 3-carbon compound.GlycolysisGlyco = glucoseLysis = break downLOCATION: Occurs in the cytoplasm This stage occurs in BOTH aerobic and anaerobic respirationOccurs in ALL eukaryotic cellsGlycolysis- ATP Production In the pathways beginning, 2 ATP molecules are used up.At the end of glycolysis, 4 ATP molecules are formed. NET GAIN- 2 molecules!!!Glycolysis- NADH ProductionProcess removes 4 high energy e- and passes them to nicotinamide adenine dinuclueotide (NAD+), which is an electron carrier.NAD+ turns into NADH while transferring electrons to other molecules.Steps of GlycolysisTwo ATP molecules are used to energize a glucose molecule. 2. Glucose is split into 2 3-carbon molecules. Enzymes rearrange the molecules.3. Electrons are transferred to NADP. The carbon molecules are converted to pyruvate which enters cellular respiration.Location= CytoplasmNO O2 required Energy Yield net gain of 2 ATP at the expense of 2 ATP6-C glucose TWO 3-C pyruvatesFree e- and H+ combine with organic ion carriers called NAD+ NADH + H+(nicotinamide dinucleotide)Used in ETC. Hydrogen attached to water.GlycolysisGlycolysis:Get a sheet of paper to review theprocess of glycolysis.Video: GlycolysisGlucoseTo the electron transport chainFigure 93GlycolysisGlycolysis:Step 12 Pyruvic acidGlycolysis Reactants and ProductsReactants1 glucose Enzymes are needed2 ATP are needed to startProducts2 Pyruvates (go to next step)4 ATP (2 are gained)2 NADH (go to ETC)Really 10 steps with 10 different enzymes involved.Anaerobic Respiration (without oxygen): Fermentation***fermentation does not make ATP for the cell, it cycles the ATP for glycolysis***(does not release energy in cell)Two Main types: Lactic Acid fermentation- converts pyruvic acid and NADH to lactic acid and NAD+-muscle cellsAlcoholic fermentation- converts pyruvic acid and NADH to ethyl alcohol, CO2, NAD+-yeast (air bubbles in bread)Main Goals of Krebs CycleTransfer high energy electrons(NADH and FADH2) to molecules that can carry them to the electron transport chain.Form some ATP molecules.Takes place in mitochondria Review of Mitochondria StructureSmooth outer MembraneFolded inner membraneFolds called CristaeSpace inside cristae called the MatrixCopyright CmassengaleCopyright Cmassengale*Krebs Cycle- Part A (Citric Acid Production)From glycolysis, the 3carbon molecule (pyruvic acid/pyruvate) enters the mitochondria (innermost layer- Matrix)3carbon pyruvic acid is broken down into 2carbon (Acetyl-CoA) molecules.CO2 and NADH are producedHint: anytime the number of carbons are reduced, CO2 and NADH are producedAcetyl-CoA (2carbon) combines with 4 carbon compounds forming a 6 carbon molecule Citric acid. Krebs CyclePart B (Energy Extraction)The 6carbon Citric Acid broken down into 5 carbon compound (releasing CO2 & NADH)5 carbon compound broken down into 4 carbon compound (releasing CO2 & NADH)In a series of 4carbon to 4carbon reactions, ATP, CO2, NADH & FADH2 are producedRemember: NADH & FADH2 are electron carriers that will take the electrons to the ETCKreb CycleKrebs Cycle Reactants and ProductsReactants2 Acetyl CoA (pyruvic acid)Remember when you form a bond energy is released!! This is the key!!Products2 ATP8 NADH (go to ETC)2 FADH2 (go to ETC)6 CO2 (given off as waste)Diagram of the ProcessOccurs in CytoplasmOccurs in MatrixOccurs across CristaeCopyright CmassengaleCopyright Cmassengale*Krebs CycleElectron Transport ChainWhere inner membrane of mitochondria called cristea.Energy Yield Total of 32 ATPO2 combines with TWO H+ to form H2OExhale - CO2, H2O comes from cellular respirationVideo: ETCElectron Transport ChainSection 9-2Electron TransportHydrogen Ion MovementATP ProductionATP synthaseChannelInner MembraneMatrixIntermembrane SpaceMitochondrionElectron Transport - Step 31. Proteins inside the membrane of the mito. Remove electrons from NADPh and FADH.Electrons(hydrogen) are transported down the chain of the membrane to be pumped across.ATP synthase(enzyme) puts a P on ADP to make ATP(END GOAL!!).Oxygen enters the cycle to pick up electrons and hydrogen ions to make water that leaves the cycle.Electron Transport ChainElectron carriers loaded with electrons and protons from the Krebs cycle move to this chain-like a series of steps (staircase).As electrons drop down stairs, energy released to form a total of 32 ATP Final Goal!!Oxygen waits at bottom of staircase, picks up electrons and protons and in doing so becomes water Diagram of the ProcessOccurs in CytoplasmOccurs in MatrixOccurs across CristaeCopyright CmassengaleCopyright Cmassengale*Energy Tally36 ATP for aerobic vs. 2 ATP for anaerobicGlycolysis 2 ATPKrebs 2 ATPElectron Transport32 ATP 36 ATPAnaerobic organisms cant be too energetic but are important for global recycling of carbonFlowchartSection 9-2Glucose (C6H1206)+Oxygen (02)GlycolysisKrebs CycleElectron Transport ChainCarbon Dioxide(CO2)+Water(H2O)+ATPCellular Respiration**********************

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