To energize or not to energize? What is energy anyway?

Energy A. definitions 1. energy 2. work 3. thermal energy

4. Types of energy a. Kinetic energy b. Potential energy

Potential vs. Kinetic Energy

5. Open vs. closed systems

6. Entropy

7. Types of chemical reactions a. endergonic stores energy decreases entropy not spontaneous requires energy input Biological example

7. Types of chemical reactions Exergonic reactions you know what to put here from the previous slide

8. Metabolism

What type of reaction is illustrated in the diagram below? Anabolic Exergonic Catabolic One that increases entropy Free energy (G)

B. Laws of thermodynamics 1. First Law Definition Repurcussions

Plants, being autotrophs, create their own energy. True False

2. Second law of thermodynamics Energy conversions are not 100% effective When energy changes form, some energy is lost as waste heat Entropy is always increasing

Life creates order. The second law of thermodynamics says that disorder is always increasing. Do living systems violate the second law of thermodynamics? Yes No I don’t know

Explanation of question

C. Importance of ATP Energy currency of cell Produced in the mitochondria and chloroplasts Used whenever the cell needs to perform work

Molecular Structure of ATP

II. Nature of chemical reactions-chaotic A. Chaotidc

II. Nature of chemical reactions B. Sometimes a productive collision occurs Powerful Correctly oriented Enough speed to overcome electron repulsion

II. Nature of chemical reaction C. Transition state forms Represents high energy state Very unstable Very short lived Old bonds are broken New bonds form

What type of reaction occurred in this reaction? Catabolic Dehydration Hydrolysis Ionic bond formation Both 1 & 2

II. Nature of chemical reactions C. Types of chemical reactions Exergonic reaction Endergonic reaction Energy coupling

III. Energetics of chemical reactions A. Energy profile at room temperature

III. Energetics of chemical reactions B. Tricks chemists play add heat stir increase concentration of reactants increase pressure on reactants add a catalyst

Effect of heating a chemical reaction

Effect of increasing the reactants’ concentrations

IV. How Enzymes Work A. Normally

B. Characteristics of enzyme function

C. Effect on energy dynamics

D. Molecules at biological temperatures

E. Analogy of Volkswagon on the hill