Activation Energy

• Activation energy


  The amount of energy required for a chemical reaction to proceed
• Enzymes


  • They lower the activation energy of the chemical reactions that they catalyse
• How enzymes speed up reactions


  1. Enzyme binds to substrate

  2. Stresses and destabilises bonds in substrate

  3. Reduces overall energy level of substrate's transitionary state

  4. Less energy needed to convert substrate into product

  5. Reaction proceeds at faster rate
• Exergonic reactions


  Reactants contain more energy than products, free energy is released into the system
• Catabolic reactions


  Breaking down, energy is released from broken bonds within a molecule
• Endergonic reactions


  Reactants contain less energy than products, free energy is lost to the system
• Anabolic reactions


  Building up, energy is required to synthesise bonds between molecules
• Exergonic process


  Reactants contain more energy than products, free energy is released
• Endergonic process


  Reactants contain less energy than products, free energy is lost