Cellular RespirationProcess by which cells release energy from molecules of food.Carbohydrates, fats and proteins all contain energyThis energy is released gradually in a series of reactions controlled by enzymes.Release energy is stored as ATP for later use.ATP is the currency of the cell.
The Chemical EquationC6H12O6 + 6 02 6CO2 + 6H2O + 38 ATPGlucose + Oxygen Carbon Dioxide + Water + Stored Energy 2 ATP are used to make this process take place Net Gain = 36 ATP for 1 molecule of Glucose
4 Main Steps in RespirationGlycolysisIntermediate ReactionKrebs Citric Acid CycleElectron Transport System
Glycolysis2 ATP are used to start the processGlucose is split into 2 3-carbon pyruvic acid moleculesSome Hydrogen is released4 ATP are made, a net gain of 2 ATPIt occurs in virtually all cells. In eukaryotes, it occurs in the cytosol.
Intermediate ReactionTakes place in the mitochondria (powerhouse of the cell)Breakdown of the 2 3-carbon pyruvic acid molecules2 carbon fragments, acetic acid are formed and2 CO2 and more hydrogen are releasedAcetic Acid is carried by Acetyl CoA to Kreb Cycle
Krebs Citric Acid CycleBreakdown ContinuesFour more CO2 are releasedMany more Hydrogen are released and picked up by NAD+ to form NADHTwo more ATP are made
Electron Transport SystemHydrogen atoms are transferred to bond with oxygen atoms to make water32 ATP are made e- power e- carriersWater wheelNet Result36 ATP produced
Oxygen is vital!It is the final acceptor of electrons without it the process stops.Pyruvic acid is converted to lactic acid, which accumulates in muscles causing fatigue and soreness.