1. The Direction of Spontaneous Reactions (and what it takes to go the other way)

2. Life Requires Lots of Unfavorable Reactions – How Is This Possible?

3. The “Nature of Life” – Coupling Favorable to Unfavorable Reactions

4. ATP – LIFE’S ENERGY CURRENCY ATP = Adenosine Triphosphate Energy is released when ATP is hydrolyzed (broken down by water) to ADP. ATP is restored from ADP and an input of energy. ATP’s energy is used to drive endergonic (energy-requiring) reactions.

5. ENZYMES SPEED UP CHEMICAL REACTIONS Enzymes are biological catalysts – substances that speed a reaction without being altered in the reaction. Most enzymes are proteins. Enzymes are essential for life. Model of the surface of an enzyme.

6. Enzymes Lower a Reaction’s Activation Energy

7. ENZYME ACTION

8.  http://highered.mcgraw- hill.com/sites/0072495855/student_view0/cha pter2/animation__how_enzymes_work.html http://highered.mcgraw- hill.com/sites/0072495855/student_view0/cha pter2/animation__how_enzymes_work.html

9. The Fit Between Enzyme and Substrate is Critical and Precise Hexokinase, an enzyme (blue), binding its substrate, glucose (yellow).

10. ENZYME DEFICIENCY AND HEALTH Most genetic disorders are due to a deficiency in enzyme function. This archival photo shows three children with the enzyme deficiency that causes phenylketonuria.

12.  Temperature and pH effect enzyme action