Chapter 25

1. Chapter 25 Metabolism and Energetics

2. replacement / repair recycling / breakdown cell growth / division store nutrients special jobs (secretion/contraction,…) chemical reactions:

3. (Cell) Metabolism the sum of all the chemical reactions taking place in an organism (a cell)

4. Catabolism breakdown of organic substances (release energy) Anabolism synthesis of new organic substances

5. fig. 25-1

6. Cellular respiration glucose + 02 H20 + CO2 + ATP

7. Cellular respiration 3 subpathways: glycolysis TriCarboxylicAcid cycle (TCA) Electron Transport System (ETS)

8. 3 subpathways each individual step each chemical structure the names of each enzyme glucokinase glucose glucose-6-phosphate + ATP + ADP

9. 3 subpathways beginning and end net gain for each important intermediates important byproducts other features ??

10. O2? fig. 25-3

11. (anaerobic) Glycolysis breakdown glucose (C6) produce 2 pyruvate (C3) net gain 2 ATP 2 NADH (coenzyme)

12. yield NAD and CoEnzyme A (CoA) pyruvate acetyl-CoA irreversible + CO2 + NADH (x 2)

13. Tricarboxylic acid cycle citric acid cycle reb’s cycle oxaloacetate fig. 25-4

14. 3 2 6 4 5 4 fig. 25-4b

15. cumm. yield TCA yield 6 CO2 4 ATP 8 NADH 2 FADH2 2 NADH 2 CO2 ATP 3 NADH 1FADH2 4 CO2 2 ATP 6 NADH 2 FADH2 x 2 TCA glycolysis

16. Electron Transport System and Oxidative Phosphorylation (production of ATP using O2) 2 H2O 2 H2 + O2

17. Slide 5 Figure 25-5 cytochromes

19. fig. 25-6

20. glucose + 02 H20 + CO2 + ATP Cellular respiration glucose + 6 02 6 H20 + 6 CO2 + 36 ATP

21. Can cells produce glucose? Yes, but… not just “undoing” glycolysis pyruvate acetyl-CoA irreversible

22. glycolysis gluconeogenesis

23. fig. 2-15

24. fig. 2-15

25. fig. 2-15

26. H H H C C=C C=C C C C H cis- trans- fig. 2-15

27. beta oxidation • remove C-C fragments • as acetyl-CoA TCA cycle, ETS 16 ATP

28. 16 ATP each C-C 9 C-C fragments each 18 C chain 18 C chain (stearic acid) 9 C-C fragments X 9 x 16 = 144 ATP 18 C fatty acid

29. 3 X 36 = 108 ATP 18 C - glucose = ? glucose molecules 3 18 C chain x ?? ATP/glucose 36 9 x 16 = 144 ATP 18 C - fatty acid

30. fig. 25-8

31. Lipid synthesis acetyl-CoA many cholestrol, steroids, …

32. fig. 25-3 Lipid synthesis acetyl-CoA many DHAP glycerol

33. Lipid synthesis acetyl-CoA many DHAP glycerol • some lipids are essential • we can’t make them • we have to ingest them • linoleic acid, linolenic acid

34. Lipid transport (not soluble in H2O) FFA (free fatty acids) • carried by albumin • most abundant blood plasma protein)

35. Lipid transport FFA (free fatty acids) • Lipoproteins - • lipid-protein complexes • coated by phospholipids • and protein • Classification: LDL’s HDL’s

36. Cholesterol: is necessary component of membranes precursor for steroid hormones can be made by our cells but,… too much is unhealthy obtained from saturated fats

37. fig. 25-?

38. LDL low density lipoprotein • contain cholesterol • carry it to peripheral tissues • If levels of cholesterol are • high is can accumulate in • places like arterial walls • (atherosclerosis)

39. HDL high density lipoprotein • transport excess cholesterol • back to liver

40. Slide 10 fig 25-9b

41. total cholesterol 200 mg dl factors affecting [cholesterol] • genetics • age • physical condition • diet < pg. 929

42. Protein metabolism General info: • 100,000 to 140,000 • linear arrays of amino acids • 20 different amino acids • (similarities)

43. O OH C | HCN amino acid

44. carboxylic acid O OH C | H CNH2 | R amine variable amino acid

45. NH2 protein catabolism O OH C | HC amino acid

46. O || C NH2 H2N Deamination • produces NH4+ • (ammonium ion) urea cycle +H2O 2 NH3 + CO2

47. Proteins and energy production • more difficult to break up • than carbohydrates or lipids • byproduct (NH4+) is toxic • they serve very important roles

48. fig. 25-10

49. Phe Tyr PKU phenylketouria inborn errors of metabolism phenylalanine hydoxylase

50. PKU phenylketouria