6H 2 O + 6CO 2 + ATPC 6 H 12 O 6 + 6O 2 

Recycling of Molecules for energy production

Glycolysis Pyruvate Oxidation Krebs Cycle ETC 2 ATP 2 NADH 6 NADH 2 FAD 2 ATP 34 ATP IN THE PRESENCE OF OXYGEN IN THE ABSENCE OF OXYGEN

Where do the reactants and products go? c6H12O6 + 6O2  38 ATP + 6H2O + 6CO2 GlucoseCut up in glycolysis OxygenReactant in ETC WaterProduct of ETC CO2Product of Krebs Cycle 38 ATPProduct from Glycolysis (2), Krebs(2), ETC(34)

Copyright Cmassengale 3 Phosphates Ribose Sugar Adenine Base

It supplies YOU with ENERGY! Copyright Cmassengale

By breaking the high- energy bonds between the last two phosphates in ATP Copyright Cmassengale

HYDROLYSIS (Adding H 2 O) Copyright Cmassengale H2OH2O

ATP-ase ATP Synthetase

Cellular respiration is a Redox reaction as the transfer of one or more electrons from one reactant to another occurs Oxidation is the loss of electrons Reduction is the addition of electrons. Because the electron transfer requires a donor and an acceptor, oxidation and reduction always go together.

The breakdown of glucose is exergonic. This means that the products store less energy than the reactants The basic purpose of respiration 6H 2 O + 6CO 2 + ATPC 6 H 12 O 6 + 6O 2  Energy releasedEnergy re-captured

So where does this released energy go? Electrons are shuffled around and passed through several cycles to eventually be used to bond ADP and P i to form ATP The basic version of how it works…

NAD + (nicotinadenine dinucleotide) acts as the energy carrier NAD + (nicotinadenine dinucleotide) acts as the energy carrier NAD + is a coenzyme NAD + is a coenzyme It’s Reduced to NADH when it picks up two electrons and one hydrogen ion It’s Reduced to NADH when it picks up two electrons and one hydrogen ion Copyright Cmassengale

YES! Another Coenzyme! YES! Another Coenzyme! FAD+ (Flavin adenine dinucleotide) FAD+ (Flavin adenine dinucleotide) Reduced to FADH 2 Reduced to FADH 2 Copyright Cmassengale

Metabolic Pathway that breaks down carbohydrates Metabolic Pathway that breaks down carbohydrates Process is Exergonic as High-energy Glucose is broken into CO 2 and H 2 O Process is Exergonic as High-energy Glucose is broken into CO 2 and H 2 O Process is also Catabolic because larger Glucose breaks into smaller molecules Process is also Catabolic because larger Glucose breaks into smaller molecules Copyright Cmassengale

Direct Phosphorylation

6CO 2 + 6H e ATP’s C 6 H 12 O 6 + 6O 2 YIELDS Copyright Cmassengale

Four Stages of Cellular Respiration Glycolysis – cutting glucose to make pyruvate Pyruvate Oxidation – cutting pyruvate to make CoA Krebs Cycle - making NADH and FADH Electron Transport – Converting to ATP

Glycolysis Splits a glucose molecule into Carbon molecules called PYRUVATE PYRUVATE. Input: C 6 H 12 O 6, (2ADP, 2Pi, 2NAD) products: 2 H 2 O, 2 pyruvate, ( 2 ATP, 2NADH ) C-C-C-C-C-C C-C-C

Glycolysis

Pyruvate Oxidation The pyruvate looses a carbon leaving the 2 carbon molecule Acetyl CoA CC CO 2 Input: Pyruvate + O2 products: CO 2, Acetyl CoA and 2 NADH C-C-C + O > C-C + CO2

Takes place in the Cytoplasm Anaerobic (Doesn’t Use Oxygen) Glucose split into two molecules of Pyruvate or Pyruvic Acid Requires input of 2 ATP Produces 2 NADH and 4 ATP Pyruvate is oxidized to Acetyl CoA and CO 2 is removed Copyright Cmassengale

ATPNADHFAD Glycolysis + Pyruvate oxidation 240

The Krebs Cycle “a bit of chemical magic happens” Inputs: Acetyl CoA, H 2 O, (FAD, NAD, ADP, Pi) Products: CO 2 ATP, NADH, FADH

Requires Oxygen (Aerobic) Requires Oxygen (Aerobic) Cyclical series of oxidation reactions that give off CO 2 and produce one ATP per cycle Cyclical series of oxidation reactions that give off CO 2 and produce one ATP per cycle Turns twice per glucose molecule Turns twice per glucose molecule Produces two ATP Produces two ATP Takes place in matrix of mitochondria Takes place in matrix of mitochondria Copyright Cmassengale

Each turn of the Krebs Cycle also produces 3NADH, 1FADH 2, and 2CO 2 Each turn of the Krebs Cycle also produces 3NADH, 1FADH 2, and 2CO 2 Therefore, For each Glucose molecule, the Krebs Cycle produces 6NADH, 2FADH 2, 4CO 2, and 2ATP Therefore, For each Glucose molecule, the Krebs Cycle produces 6NADH, 2FADH 2, 4CO 2, and 2ATP Copyright Cmassengale

ATPNADHFAD Glycolysis + Pyruvate oxidation 240 Krebs cycle262

Electron Transport The mitochondria has two membranes--the outer one and the inner membrane which is convoluted. The H+ which are brought to mitochondria accumulate between these two membranes.

matrix H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ outer membrane inner membrane ( ATP synthetase) The matrix is a protein rich solution which contain the enzymes which run electron transport. ATP SYNTHETASE is the enzyme which is responsible for making ATP. Mitochondria H+H+ H+H+ NAD H+H+

34 ATP Produced 34 ATP Produced H 2 O Produced H 2 O Produced Occurs Across Inner Mitochondrial membrane Occurs Across Inner Mitochondrial membrane Uses coenzymes NAD+ and FAD+ to accept e- from glucose Uses coenzymes NAD+ and FAD+ to accept e- from glucose 1 x NADH can create 3 ATP’s 1 x NADH can create 3 ATP’s 1 x FADH 2 can create 2 ATP’s 1 x FADH 2 can create 2 ATP’s Copyright Cmassengale

ments/Biology/Bio231/etc.html

The electrons are passed back and forth across the membrane where their energy is gradually decreased and used to transport H + through the membrane. Oxygen is the final electron acceptor and it joins with the H + to produce H 2 O. If there is no oxygen, the electron chain cannot continue (nothing to accept the H+ atoms the cross the membranes) because there is no way to release electrons (nothing to accept the H+ atoms the cross the membranes) electrons Inputs: NADH, FADH, H +, ADP, P i, O 2 Outputs: NAD +, ATP, FAD, H 2 O INPUT AND OUTPUT OF ETC

Products of the Electron Transport Chain 34 ATP Water +

ATPNADHFADH Glycolysis + Pyruvate oxidation Krebs cycle ETC Total+3800 The ETC withdraws NADH and FADH 8 NADH to create 24 ATP 2 FADH to create 4 ATP

glycolysis NADH carries electrons to ETC prep Krebs Electron Transport chain ATP 2 2 NADH

What happens when there is no oxygen to accept the electrons? to accept the electrons? Only the process of glycolysis is carried out and lactic acid is produced in the muscles. The body cannot tolerate much lactic acid and it must eventually be converted in the liver to pyruvate. results in muscle soreness

Alcoholic Fermentation Some organisms carry out alcoholic fermentation. This was discovered by Louis Pasteur in his study of the chemistry of wines. Yeasts break down the sugars in the juice to pyruvate by glycolysis, then the pyruvate is dismantled to yeild CO 2 and ETHANOL. If the fermentation continues until all the sugar is used, a dry wine is produced. If fermentation is stopped before all the sugar is used, then a sweet wine is produced.

Same process, different products