2. First Law of Thermodynamics: Energy can change from one form to another but it can never be destroyed, nor can new energy be made. Second Law of Thermodynamics: Disorder in the universe is constantly increasing.

4. Make or break bonds Change molecules Chemical Reactions

5. A + B  C + D ReactantsProducts

6. Likelihood a reaction will occur 1. depends on energy a. is energy input needed? if so, then the products will have more energy than the reactants (see 1st Law of Thermodynamics) b. will the reaction occur spontaneously? if so, then the products will have less energy than the reactants (see 2nd Law of Thermodynamics) energy is “released”

7. A + B + energy  C Endergonic Includes synthesis reactions

8. A  B + C + energy Exergonic Includes breakdown reactions

10. 2. activation energy a. energy required to initiate a chemical reaction b. high for endergonic reactions, low for exergonic reactions

11. c. catalysis process of lowering the activation energy can speed up a chemical reaction

12. Enzymes Are catalysts, binding to molecules in such a way as to make a reaction more likely to occur

13. A. Specificity 1. only specific reactants will fit into the enzyme 2. binding sites (active sites) 3. lock and key model

14. B. Lowers the activation energy 1. puts stress on bonds in reactant molecules 2. brings reactants into close proximity or proper orientation

15. C. The enzyme is unchanged by the reaction D. The enzyme does not alter the nature of the reaction or the end result

17. Factors Influencing Rate

18. cofactors metal ions can cause conformational changes in enzymes can participate in bonding of substrates and active sites

19. Factors Influencing Rate coenzymes small organic molecules transport H from one molecule to another derived from water-soluble vitamins NAD FAD nicotinamide adenine dinucleotide flavin adenine dinucleotide

25. + 6O 2  6CO 2 + 6H 2 O + energy* Exergonic reaction releasing free energy C 6 H 12 O 6

26. Endergonic reaction: synthesis of ATP ADP + Pi + free energy*  ATP* *Free energy comes from breakdown of organized molecules (i.e., glucose)

27. Endergonic reaction driving synthesis of organized molecules glucose + fructose + *energy  sucrose* *Energy comes from the hydrolysis (breakdown) of ATP.

28. Oxidation/Reduction Reactions oxidation: loss of electrons reduction: gain of electrons