Metabolism Energy of Life Metabolic Pathways Anabolic Pathways
Metabolism Energy of Life
Metabolic Pathways Anabolic Pathways Catabolic Pathways
Kinetic Energy
Potential Energy
Laws of Thermodynamics
First Law of Thermodynamics Energy can be transferred or transformed but it cannot be created or destroyed
Second Law of Thermodynamics Every energy transfer or transformation increases the entropy of the Universe
Free Energy J. Willard Gibbs (1839 -1903) Yale Professor Mathematical physics Gibbs Equation DG = DH – TDS DG – Change in Free energy DH – Change in Total energy (Enthalpy) T – Absolute temperature in Kelvin DS – Change in Entropy
Free Energy and Metabolism
Free Energy and Metabolism Exergonic Reactions Release of energy -DG Spontaneous Downhill More energy in reactants than in products Ex. Cellular Respiration • -686 kcal/mol Ex. ATP ADP + P • -7. 3 kcal/mol Endergonic Reactions Absorbs energy +DG Nonspontaneous Uphill More energy in products than in reactants Ex. Photosynthesis • +686 kcal/mol Ex. ADP + P ATP • +7. 3 kcal/mol
Adenosine Triphosphate
Energy Coupling using ATP hydrolysis
How ATP Performs Work
The ATP Cycle
Enzymes Biological Catalyst Speed up metabolic reactions by lowering the energy of activation
Exergonic Reaction
Exergonic Reaction with Enzyme
Enzymes Substrate Specific Active Site Induced Fit Recycled
Enzymes Cofactors Coenzymes
Enzymes Inhibitors Competitive Noncompetitive
Enzymes Allosteric Sites Cooperativity
Feedback Inhibition Pathway switched off
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