1. Learning Target: Enzymes in Action Part I

2. Learning Target #1: Enzymes I Can… Describe the general role of enzymes in metabolic cell processes. I Will… Describe the components of metabolic chemical reactions. Define the terms; reactant, product, bond energy, and activation energy. Explain what occurs during endo- and exo-thermic reactions in terms of bond and overall energy

3. Enzymes are the Super Heroes of Homeostasis! KEY IDEA: Life depends on chemical reactions Metabolism –  All the chemical reactions that take place in your body and cells.  Anabolism – joining materials together  Catabolism – breaking materials apart Why?

4. Reactants – substances changed during a chemical reaction (Rxn). Products – substances made during a chemical Rxn. Chemical bonds are broken and formed. Bond energy – energy required to break a bond between two atoms. Reactants Yield sign Products

5. Activation energy – energy that must be absorbed by the reactants before the chemical Rxn can take place.

6. Endothermic Rxn – Overall net energy is absorbed. Reactants have low bond energy. Products have high bond energy. More energy must go into the reaction and is stored in the bonds of the products.

7. Exothermic Rxn – Overall net energy is released. Reactants have high bond energy. Products have low bond energy. Excess energy goes out of the reaction while little is stored in the bonds of the products