2. Chemical Reactions and Enzymes

3. What is a chemical reaction? Changes or transforms chemicals into other chemicals Ex: Iron + Oxygen  Iron Oxide (rust) What is the product? What are the reactants?

4. Energy Is Required Energy can be either given off or absorbed for a chemical reaction to occur Identify the type of reaction as either endothermic or exothermic by the graphs to the right:

5. Activation Energy Energy needed to start a reaction Identify the activation energy supplied for the following chemical reactions 1)Building a Fire 2)Turning on a Light 3)Starting a Car

6. Catalyst Any substance that lowers the activation energy needed to start a reaction.

7. Enzymes Baby!!!!!! Describe what enzymes “do” using the graph below:

8. Enzymes Enzymes are proteins made by the cell to speed up the chemical reactions.

9. Properties of Enzymes 1.Lowers activation energy 2.Speeds up a reaction 3.Can be used repeatedly 4.Shape specific (substrate)* *If shape is altered, enzyme cannot function Animations http://www.lewport.wnyric.org/jwanamaker/animati ons/Enzyme%20activity.html

10. Factors That Affect Enzyme Activity High Temperature (boiling ) Extreme pH – (acid/base) Changes enzyme shape

11. Denaturing an Enzyme A change in the shape of the active site on the enzyme

13. What life molecule are enzymes a part of??? PROTEINS!

15. Enzymes = speed up reactions (to break down substances) Substrate= a molecule which is acted upon by an enzyme (the reactant)

18. “ase” Enzymes have an ending “ase” It helps you identify which one is the enzyme and which one is the substrate.