1. An Introduction to Metabolism AP Biology

2. Metabolism The emergent property of life that arises from interactions between molecules within the orderly environment of a cell. A sum of all the chemical reactions within a cell.

3. Thermodynamics 1 st Law: – Energy can be transformed or transferred but not created or destroyed. – Conservation of energy 2 nd Law: – Every energy transformation or transfer increases the entropy (disorder) of the universe. How can we reconcile the fact that life is orderly with the 2 nd Law?

4. Free Energy The portion of a system’s energy that can be used to perform work. It is available for work but is spent at a cost to the universe.

5. Exergonic vs. Endergonic SpontaneousNon-spontaneous

6. STOP for a Vocabulary Check “Break down” reaction: – Catabolic – Spontaneous – Exergonic – Degradative process (breaking things down) – Downhill reaction – ∆G ‹ 0 Free energy is negative “Build up” reaction: – Anabolic – Non-spontaneous – Endergonic – Synthesis process (building things up) – Uphill reaction – ∆G › 0 Free energy is positive

7. Energy coupling Exergonic process drive an endergonic one.

8. Phosphorylation ATP performs work by transferring the inorganic phosphate to another molecule.

9. ATP Regeneration

10. Enzymes Serve as a catalyst to speed up the rate of reactions without being consumed by the reaction. They are reusable!

11. Activation Energy

12. Enzymes are Substrate Specific

13. Inhibition of Enzymes Allosteric site: location on an enzyme that can either increase or decrease an enzyme’s activity.

14. Feedback Inhibition