Ch. 6: An Introduction to Metabolism

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Ch. 6 An Introduction to Metabolism

• The chemistry of life..

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Metabolism

• Catabolic pathways
• e.g. cellular respirations
• Anabolic pathways
• e.g. protein synthesis

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Organisms transform energy

• Energy
• KE Kinetic Energy, energy in motion
• PE Potential Energy, energy stored
• energy can be transformed from one form to
  another

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Laws of Thermodynamics

• The first law of thermodynamics
• E is neither created or destroyed
• The second law of thermodynamics
• Entropy
• organisms live at the expense of free energy
• exergonic reactions
• endergonic reactions

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Disequilibrium

• Cell that reaches equilibrium is dead
• Open System
• Sequence of reactions
• Coupling use of an exergonic process to drive
  an endergonic one

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Why do I have to do all this work!
ATP
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ATP

• structure
• chemical reaction that results in the release of
  energy
• How does ATP perform work? Phosphorylation
  Transfer
• Regeneration of ATP

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Phosphorylation of ATP
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ATP

• that 107 molecules of ATP are used and then
  regenerated per second per cell?

Did you know?
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Enzymes

• Speed up reaction rate Catalyst

• Catalytic Protein
• Activation Energy needed

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Exergonic Reaction

• Enzymes lower barrier of activation energy
• Does not speed up reaction. Hastens reactions
  that would occur normally.

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Enzymes Active Site
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Inhibition of Enzymes
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The control of metabolism

• regulated by controlling enzyme activity
• allosteric regulation
• feedback inhibition
• cooperativity
• location of enzymes in the cell