Biochemistry

1. Biochemistry

2. Most life processes are a series of chemical reactions influenced by environmental and genetic factors.

3. Metabolism • the sum of all biochemical processes

4. 2 Metabolic Processes • Anabolism- the building up of complex molecules • Catabolism- the breaking down of complex molecules

5. Most cells function best within a narrow range of temperature and pH. • At very low temperatures, reaction rates are too slow. • High temperatures or extremes of pH can irreversibly change the structure of proteins and alter their function.

6. The main components of a living cell are: • Carbon • Hydrogen • Nitrogen • Oxygen • -Phosphorus • -Sulfur

7. Inside every cell is a concentrated mixture of thousands of different macromolecules forming a variety of specialized structures that carry out cell functions, such as: • energy production • transport • waste disposal • synthesis (creation) of new molecules • storage of genetic material.

8. Organic Compounds • Compounds that contain CARBON and are living or once living are called organic. • Macromolecules are large organic molecules.

9. Carbon (C) • Carbon has 4 electrons in outer shell • Carbon can form covalent bonds with as many as 4 other atoms (elements) • Usually with H, O, N, or C • Example:C6H12O6 (sugar)

10. Carbon forms four covalent bonds, producing many shapes

11. Functional groups Groups of atoms that determine the types of chemical reactions and associations Most readily form associations with with other molecules

12. Functionalgroups Hydroxyl Carbonyl Carboxyl Amino Phosphate Sulfhydryl

13. Macromolecules • Large organic molecules. • Also called POLYMERS. • Made up of smaller “building blocks” called MONOMERS. • Examples: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids (DNA and RNA)

14. Polymers Most macromolecules are polymers Produced by linking monomers

15. A simplepolymer

16. CONDENSATION (DEHYDRATION) SYNTHESIS

17. HYDROLYSIS

18. Condensation Enzyme A Hydrolysis Monomer Monomer Dimer Enzyme B

19. 1. Carbohydrates • Small sugar molecules to large sugar molecules. • Examples: A. monosaccharide B. disaccharide C. polysaccharide

20. Carbohydrates Sugars Starches Cellulose Carbohydrate means hydrate (water of) carbon Reflects 2:1 ratio of hydrogen to oxygen

21. glucose 1. Carbohydrates A. monosaccharide: one sugar unit • Examples: glucose (C6H12O6 blood sugar) deoxyribose ribose galactose (milk sugar) fructose (honey)

22. fructose glucose B. disaccharide: two sugar unit • Example: sucrose = glucose + fructose

23. Enzyme Maltose C12H22O11 Glucose C6H12O6 Glucose C6H12O6 (a) Enzyme Sucrose C12H22O11 Glucose C6H12O6 Fructose C6H12O6 (b)

24. glucose glucose glucose glucose cellulose glucose glucose glucose glucose C. polysaccharide: many sugar units • Examples: starch (bread, potatoes) glycogen (beef muscle) cellulose (lettuce, corn) chitin (exoskeletons)

25. STORAGE POLYSACCHARIDES • STARCH (PLANTS) • GLYCOGEN (ANIMALS)

26. Amyloplasts (a)

27. STRUCTURAL POLYSACCHARIDES • CELLULOSE (PLANT CELL WALLS)

28. CHITIN – INSECT EXOSKELETONS AND FUNGI CELL WALLS

30. (b)

31. The primary functions of carbohydrate macromolecules are to: • provide and store energy.

32. 2. Lipids • General term for compounds which are not soluble in water. • Lipids are soluble in hydrophobic solvents. • Remember:“stores the most energy”

33. 2. Lipids • Examples: 1. Fats 2. Phospholipids 3. Oils 4. Waxes 5. Steroid hormones 6. Triglycerides

34. 5 functions of lipids: 1. Long term energy storage (fat) 2. Protection against heat loss (insulation) 3. Protection against water loss & germs (oils & waxes) 4. Chemical messengers (hormones & steroids) 5. Major component of membranes (phospholipids)

35. O C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 = H H-C----O H-C----O H-C----O H O C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 = O C-CH2-CH2-CH2-CH fatty acids = =CH-CH2-CH2-CH2-CH2-CH3 glycerol • Triglycerides: composed of 1 glycerol and 3 fatty acids.

36. O C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 = saturated O C-CH2-CH2-CH2-CH = unsaturated =CH-CH2-CH2-CH2-CH2-CH3 • There are two kinds of fatty acids you may see on food labels: 1. Saturated fatty acids: no double bonds (bad) 2. Unsaturated fatty acids: double bonds (good)

37. (c) Palmitic acid (d) Oleic acid (e) Linoleic acid

38. Saturated fatty acids contain maximum possible number of hydrogen atoms Unsaturated fatty acids include one or more adjacent pairs of carbon atoms joined by a double bond Monounsaturated fatty acids—one double bond Polyunsaturated fatty acids—more than one double bond

39. Triacylglycerol, the main storage lipid

40. A phospholipid and a phospholipid bilayer

41. (a) Phospholipid (lecithin) Choline Phosphate group Glycerol Fatty acids Hydrophilic head Hydrophobic tail

42. (b) Phospholipid bilayer Water

43. Carotenoids Orange and yellow plant pigments Classified with lipids Play a role in photosynthesis Consist of isoprene units Animals convert to vitamin A

44. Steroids • Carbon atoms in four attached rings • Consist of isoprene units • Cholesterol, bile salts, etc. • Involved in regulating metabolism

45. Cholesterol Indicates double bond (a)

46. 3. Proteins (Polypeptides) • Amino acids (the building blocks of protein) • 2 kinds of amino acids • essential & non-essential amino acids • Essential amino acids cannot be synthesized by our body & need to be obtained through our diet

48. Proteins Macromolecules composed of amino acids Most versatile cell components Most enzymes are proteins Proteins largely determine what a cell looks like and how it functions

50. 7 functions of proteins: 1. Storage: albumin (egg white) 2. Transport: hemoglobin 3. Regulatory: hormones 4. Movement: muscles 5. Structural: membranes, hair, nails 6. Enzymes: cellular reactions 7. Defense: antibodies