1. The Energy of Life
Chapter 8.4

2. BIG Idea 2
Biological systems utilize free energy and molecular building blocks to grow, to reproduce, and to maintain dynamic homeostasis.

3. Molecular Building blocks
Biological Atoms:
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus
Sulfur
Biological Molecules:
Water (H2O)
Carbohydrates
Lipids
Proteins
Nucleic Acids

4. biochemical reactions
Molecules rearrange within a living organisms for various processes essential for life.
These biochemical reactions are facilitated by a type of protein called an enzyme.

5. Enzyme Structure
The most structurally sophisticated molecules in existence
Synthesized through gene expression (DNA  RNA  Protein)

6. Enzyme Function (beginning)
Biochemical reactions are usually not spontaneous
Initial investment of energy to start a reaction
Enzymes lower the Ea of a reaction

7. Enzyme Function (middle)
Enzymes and substrates interact at the active site:
Induced Fit: enzyme changes shape
Substrate is broken down or built up
Every enzymes is substrate specific!
Hexokinase (a) without (b) with glucose substrate

8. Enzyme Function (end)
Enzymes are not used up in the reaction

9. Common Enzymes in your Body
Amylase:
in your mouth breaks down sugar
Peptidase
in your stomach break down proteins
Lipase:
in your small intestine break down lipids
~2000 enzymes in your body working right now!!!

10. Regulating Enzymes

11. Denaturing enzymes (limit range)
Heat: Denatures enzymes
pH: Acids or bases denature enzymes

12. Heat

13. pH

14. Inhibitors (Turn off) Competitive Noncompetitive
Similar in shape and attach to active site disabling the enzyme
Noncompetitive
Bind to allosteric site of the enzyme altering the shape of the active site

15. Cofactors & Coenzymes (turn on)
Helper molecules which regulate enzyme activity
Cofactors: inorganic molecules
Coenzymes: organic molecules