Chapter Objectives

1. Explain the role of catabolic and anabolic pathways in the energy exchanges of cellular metabolism
2. Distinguish between kinetic and potential energy
3. Distinguish between open and closed systems
4. Enunciate and explain the 1st and 2nd Laws of Thermodynamics
5. Explain why highly ordered living systems do not violate the 2nd Law of Thermodynamics
6. Distinguish between entropy and enthalpy
7. Write the Gibbs equation for free energy change
8. Explain how changes in enthalpy, entropy, and temperature influence the maximum amount of      usable energy that can be harvested from a reaction
9. Explain the usefulness of free energy
10. List 2 major factors capable of driving spontaneous processes
11. Distinguish between exergonic and endergonic reactions
12. Describe the relationship between equilibrium and free energy change for a reaction
13. Describe the function of ATP in the cell
14. List the 3 components of ATP and identify the major class of macromolecules to which it belongs
15. Explain how ATP performs cellular work
16. Explain why chemical disequilibrium is essential for life
17. Describe the energy profile of a chemical reaction including activation energy (EA), free energy        change ()G), and transition state
18. Describe the function of enzymes in biological systems
19. Explain the relationship between enzyme structure and enzyme specificity
20. Explain the induced fit model of enzyme function and describe the catalytic cycle of an enzyme
21. Describe several mechanism by which enzymes lower activation energy
22. Explain how substrate concentration affects the rate of an enzyme-controlled reaction
23. Explain how enzyme activity can be regulated or controlled by environmental conditions,        cofactors, enzyme inhibitors, and allosteric inhibition
24. Distinguish between allosteric activation and cooperativity
25. Explain how metabolic pathways are regulated

Chapter Terms:

Chapter Outline Framework

A. Metabolism, Energy, and Life

1. The chemistry of life is organized into metabolic pathways

2. Organisms transform energy

a. Energy
b. Kinetic energy
c. Potential energy
d. Energy transformations: Examples

3. The energy transformations of life are subject to two laws of thermodynamics

a. Thermodynamics
b. 1st Law
c. 2nd Law
d. Entropy
e. Closed System
f. Open System

4. Organisms live at the expense of free energy

a. Free energy: criterion for spontaneous change
b. Free energy and equilibrium
c. Free energy and metabolism
       · Exergonic
       · Endergonic
       · Disequilibrium

5. ATP powers cellular work by coupling exergonic to endergonic reactions

a. Mechanical work
b. Transport work
c. Chemical work
d. ATP structure and hydrolysis
e. ATP and work
f. ATP regeneration

B. Enzymes

1. Enzymes speed up metabolic reactions by lowering energy barriers

2. Enzymes are substrate-specific

a. Substrate
b. Active site
c. Induced fit

3. The active site is an enzyme's catalytic center

a. Steps in catalytic cycle b.
Mechanisms for lowering activation energy
c. Rates of enzyme-controlled reactions

4. A cell's physical and chemical environment affects enzyme activity

a. Temperature effects
b. pH effects
c. Cofactors
d. Enzyme inhibitors
       · Competitive inhibition
       · Noncompetitive inhibition

C. The Control of Metabolism

1. Metabolic control often demands allosteric regulation

a. Allosteric regulation
b. Feedback inhibition
c. cooperativity

2. The location of enzymes within a cell helps order metabolism

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