AP151 PROTEINS & ENZYME STUDY GUIDE (CHAPTER 2 & 4)
You might want to review protein structure from the chemistry chapter
RELAVENT PORTIONS OF TEXT:
TEXT: Section 2.3 (pg 41-44)
TEXT: Section 4.1 (89-97. Figures 4.1, 4.3, 4.4, 4.6, & 4.8-4.11 demonstrate key ideas.
GOAL:
To understand the physiologic importance of enzymes and the factors that affect enzyme function.
MAIN OBJECTIVES:
 To describe basic structure, function, and characteristics of proteins
 To understand the relationship between enzymes, chemical reactions, and activation energy.
 To understand the basic characteristics of enzymes and their behavior
 To understand the factors that influence enzyme function and the rate of reactions
 To understand how a series of enzymes work in sequence to form a biochemical pathway
STUDY QUESTIONS FROM CHAPTER 4:
To describe basic structure, function, and characteristics of proteins
1. What are the smaller molecules that are joined together to make a protein? (“proteins”, introductory
paragraph)
2. How many different amino acids are there? (“proteins”, introductory paragraph)
3. What is the name of the covalent bond that bond amino acids together. (Structure of Proteins)
4. If a polypeptide has more then about 100 amino acids then it is called a __________. (Structure of Proteins)
5. What is a the primary structure of a protein? (Structure of Proteins)
6. What is secondary structure? (Structure of Proteins)
7. What kinds of bonds create/maintain the secondary structure? (Structure of Proteins)
8. What is tertiary structure? (Structure of Proteins)
9. How strong are the bonds/chemical interactions that created tertiary structure? (Structure of Proteins)
10. Why can high temperatures, pH changes, and other factors easy disrupt/destroy tertiary structure ? (Structure
of Proteins)
11. What is quarternary structure? (Structure of Proteins)
12. What is a glycoprotein? Glycolipid? (Structure of Proteins)
13. List 5 general functions of proteins. (Function of Proteins)
ENZYMES, CHEMICAL REACTIONS, AND ACTIVATION ENERGY
14. What is an enzyme?
15. What is a catalyst?
16. What is activation energy?
17. What is a substrate/reactant?
18. What is a product?
19. At normal body temperature how fast would reactions typically occur (how much product would be created?) in
the absence of enzymes?
20. What problems does activation energy pose? What benefit does it provide?
21. How do enzymes speed up the rate or reactions (i.e., increase the amount of product created)?
CHARACTERISTICS OF ENZYMES AND THEIR BEHAVIOR
22. List the characteristics of enzymes?
23. Which characteristic is responsible for an enzyme’s specificity?
24. What part of the enzyme do substrates bind to?
25. What is the typical suffix (word ending) for an enzyme? Do all enzymes follow this pattern?
26. What are isozymes?
27. Can enzyme mediated reactions be reversible?
28. Can enzymes be turned on and off (be activated and inactivated)?
29. Are enzymes altered or “used up” in the reactions they mediate/promote?
30. What is denaturing and how is it related to protein tertiary structure, hydrogen bonds, and enzyme activity?
FACTORS THAT INFLUENCE ENZYME FUNCTION AND RATE OF REACTION
31. List the factors that influence the activity of an enzyme (the rate of an enzyme mediated reaction)?
32. What is meant by the term “optimum temperature”?
33. Where is the optimum temperature of most enzymes?
34. What happens to enzyme activity if there are minor to moderate deviations (above or below) from the optimal
temperature?
35. What eventually happens to enzymes with large increases in temperature? What effect does this have on
enzyme activity?
36. What happens to enzyme activity/rate of reactions with large decreases below the optimal temperature?
37. Can cold denature a protein?
38. What is meant by the terms “optimum pH”?
39. Do all enzymes have the same optimum temperature and pH?
40. What would happen to enzyme activity/reaction rates if there were small to moderate deviations from optimal
pH?
41. What would happen if there were large/extreme deviations from the optimal pH?
42. What is a cofactor and how does it relate to normal enzyme function?
43. What would happen if a cofactor is not present?
44. What are coenzymes and how do they relate to enzyme function?
45. What would happen if a coenzyme were not present?
46. Describe how substrate concentration influences enzyme activity?
47. What is enzyme saturation?
48. If enzymes had reached their saturation limit, what would need to be done to further increase the rate of
reaction?
49. How does enzyme concentration influence reaction rates?
50. What would have a higher activity, a enzyme in solution with lots of substrate or an enzyme in solution with
little substrate?
51. Enzymes are not consumed/altered by the reactions they catalyze, but do they last forever?
52. What is enzyme turnover?
53. What can phosphorylation and dephosphorylation do to enzymes?
54. What can cAMP do to enzymes?
55. What is end product inhibition?
56. How is end product inhibition similar to negative feedback?
ENZYMES AND BIOCHEMICAL/METABOLIC PATHWAYS
57. What is a metabolic/biochemical pathway?
58. What are initial substrates? Intermediates? Final products?
59. Can metabolic pathways branch (i.e., be involved with the formation of different final products)?
60. In a branching pathway what would inhibition of one branch-point enzyme do to the amount of the two final
substrates produced?
61. What do inborn errors of metabolisms have to do with enzymes and metabolic pathways?
62. What can an inborn error of metabolism do to the amount of intermediates prior to the defective enzymes? The
amount of final products after the defective enzyme?
63. What can in inborn error of metabolism do to the amount of final products of an alternate pathway?
Questions from Text/Test Your Knowledge
Chapter 4: 1, 2, 4, 5, 9, 10, 24-27