Basic Biochemistry CHE 242

1. Basic BiochemistryCHE 242 MTWR 11:00 am – 12:35 pm Julian Hall 225 Dr. Jon A. Friesen Office: 318 Science Laboratory Building phone: (43)8-7850 email: jfriese@ilstu.edu

2. What Do Biochemists Study?

3. The periodic table of the elements Figure 1.1

4. The periodic table of the elements Figure 1.1 Bulk elements 97%

5. The periodic table of the elements Figure 1.1 Essential ions

6. The periodic table of the elements Figure 1.1 Trace elements

7. Organic compounds in biochemistry Figure 1.2

8. Functional groups in biochemistry Figure 1.2

9. Linkages in biochemical compounds Figure 1.2

10. Types of molecules in biochemistry 1. Proteins Are composed of twenty different kinds of monomeric units, the amino acids. 2. Polysaccharides (sugar) Are constructed of monomeric units called monosaccharides. Also called carbohydrates. 3. Nucleic acids (DNA and RNA) Are synthesized from monomeric units called nucleotides. 4. Lipids (Fat) Water insoluble molecule containing fatty acids.Used for membrane structure and energy storage.

11. Energy Flow Page 11

12. Prokaryotic Cells Figure 1.16

13. Eukaryotic Cells Figure 1.18

14. Water, Water Everywhere

15. Water is a Polar Molecule Figure 2.1

16. Polarity of Small Molecules Figure 2.2

17. Hydrogen Bonding Between Two Water Molecules Figure 2.3

18. Water Can Form Up To Four Hydrogen Bonds Figure 2.4

19. Water Molecules Form a Hexagonal Lattice in Ice Figure 2.5

20. Sodium Chloride (NaCl) crystal Figure 2.6

21. Ionic and PolarSubstances Dissolvein Water Example: Dissolution ofSodium Chloride in water Figure 2.6

22. Glucose, a sugar, contains polar groups, and is soluble in water

23. Nonpolar substances are relatively insoluble in water

24. Noncovalent interactions in biomolecules • Charge-Charge Interactions • Hydrogen Bonds • Van der Waals Forces • Hydrophobic Interactions

27. Hydrogen bonding isa common noncovalentinteraction between biomolecules Figure 2.11

28. Hydrogen bonding between bases in DNA Figure 2.12

30. Van der Waals forces are weak noncovalentforces between atoms Figure 2.13

32. Amphipathic molecules,such as detergents,have both a polar anda nonpolar end. Figure 2.9

33. Detergents can form monolayers at the air-water interface Figure 2.10

34. Detergents can form micelles in aqueous solution Figure 2.10

35. Ionization of Water

36. Water has a slight tendency to ionize Pages 41 and 42

39. Strong acids completely dissociate in water. Example: Hydrochloric acid (HCl)

40. Weak acids dissociate in water with a characteristicacid dissociation constant (Ka). Example: Acetic acid, present in vinegar

41. Relationship between pH and pKa Henderson – Hasselbalch equation

42. Titration of acetic acid with aqueous base Figure 2.17

43. Titration of phosphoric acid,a polyproticacid, withaqueous base Figure 2.19

45. 1 2 3 4 5 6 7 8 9 10

46. Write the equilibrium reaction for the ionization of the weak acid. • What is the chemical structure of the conjugate base? • What is the pH of a solution containing equal amounts of theweak acid and the conjugate base? • What is the pH of a solution containing 10 times more weak acidthan conjugate base? • What is the ratio of conjugate base to weak acid at pH = 7?

47. Write the equilibrium reaction for the ionization of the weak acid. • What is the chemical structure of the conjugate base?

48. Write the equilibrium reaction for the ionization of the weak acid. • What is the chemical structure of the conjugate base? • What is the pH of a solution containing equal amounts of theweak acid and the conjugate base? CH3COO- 4.8 CH3COOH 1 4.8 0 4.8

49. Write the equilibrium reaction for the ionization of the weak acid. • What is the chemical structure of the conjugate base? • What is the pH of a solution containing equal amounts of theweak acid and the conjugate base? CH3COO- 4.8 CH3COOH 1 4.8 0 4.8

50. 4. What is the pH of a solution containing 10 times more weak acidthan conjugate base? CH3COO- 4.8 CH3COOH 0.1 4.8 (-1) 4.8 3.8