Ch. 8-9

Aerobic Cellular Respiration

Glycolysis

Transition Reaction

Kerbs Cycle

Electron Transport Chain

Anaerobic Cellular Respiration

Energy Coupling

Enzyme subtrate complexes

Exergonic and Endergoinc Reactions

Exergonic

A net release of free energy

Endergonic

Absorbs free energy

exergonic

endergonic

G<0

G>0

C6H12O6 + 6O2 -> 6CO2 + 6H2O

G= -686 kcal/mol (-2,870 kJ/mol)

The use of an exergonic process to drive an endergonic one

ATP is responsible for mediating most energy coupling cells

ATP +H2O -> ADP + P

G= -7.3 kcal/mol (-30.5 kJ/mol)

atp

An enzyme binds to its substrate or substrates when there are two or more reactants

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The catalytic action of the enzyme converts the substrate to the product of the reaction

Consist of a number of molecules, mostly proteins, built into the inner membrane of the mitochondria of eukaryotic cells

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Electron transfer from NADH to oxygen is an exergonic reaction with a free-energy change of -53 kcal.mol,

During cellular respiration, most electrons travel the following "downhill" route: glucose -> NADH -> electron transport chain -> oxygen

Occurs in the cytosol (cytoplasm of cell near mitochondira)

Citric acid cycle

Begins the degradation process by breaking glucose into two molecules of pyruvate

Pyruvate enters the mitochondria and is oxidized to acetyl

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Reactants

1 glucose

2NAD fro ETS

2ADP +2P

Products

2 ATP

2 Pyrruvic acid

2 NADH go to ETS

2H

Oxygen is consumed as a reactant along with the organic fuel

Found in both prokaryotic and eukaryotic cells

Obligate aerobe

When prokaryotic organisms use substances other than oxygen as reactants

Certain cells can oxidize organic fuel and generate ATP without the use of oxygen

The distinction between anaerobic respiration and fermentation is that an electron transport chain is used in anaerobic respiration

Obligate anaerobes

Facultative anaerobes

An organism that carries out only fermentation or anaerobic respiration

Can not use oxygen and in fact may be poisoned by it

An orgaism that requires oxygen for cellular respiration and cannot live without it

An organism that makes ATP by aerobic respiration if oxygen is present but that switches to fermentation or anaerobic respiration when not presented

Mitochondrial matrix

Cytoplasm -> mitochondria

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Reactants

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2 pyruvic acid

2 NAD+ from ETS

2 Coenzyme A

Products

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2CO2

2NADH-go to ETS

2 Acetyl CoA

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Products

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2 Acetyl CoA

6 NAD+ from ETS

2 ADP + 2P

2 FAD from ETS

Reactants

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4 CO2

6 NADH go to ETS

2 FADH2 go to ETS

2 ATP