1. Cellular Respiration: Harvesting Chemical Energy

2. Respiration is the process of extracting stored energy from glucose to make ATP.

3. Cellular Respiration Equation C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O and energy As a result of respiration, energy is released from the chemical bonds found in complex organic molecules (food).

4. Aerobic Respiration Aerobic Respiration is respiration which takes place in the presence of oxygen

5. Respiration is controlled by Enzymes …rate is controlled by enzymes

6. Cell Respiration is divided into 3 stages. (components) 1. Glycolysis 2. Krebs Cycle 3. Oxidative Phosphorylation

8. Glycolysis Glyco- glucose, -lysis: to split Universal step in all forms of respiration Likely used to supply energy for the ancient cells.

9. Glycolysis Function - To split glucose and produce NADH, ATP and Pyruvate (pyruvic acid). Location - Cytoplasm. Occurs in 9 steps…. 6 of the steps use magnesium Mg as cofactors.

11. NAD + Energy carrier Nicotinamide Adenine Dinucleotide NAD + + 2 e - NADH NAD + = oxidized form NADH = reduced form

12. Requirements for Glycolysis Glucose 2 ATP…. As activation energy 4 ADP 2 NAD + Enzymes

14. The Products of Glycolysis 2 Pyruvic Acids (a 3C acid) 4 ATP 2 NADH

15. Net Energy Result 2 ATP per glucose 2 NADH In summary, glycolysis takes one glucose and turns it into 2 pyruvate, 2 NADH and a net of 2 ATP.

16. Krebs Cycle Also called: Citric Acid Cycle or Tricarboxylic Acid Cycle Function: Oxidize pyruvic acid to CO 2 Produce: 3NADH, 1FADH 2 and 1ATP Location: Mitochondria matrix

17. Formation of Acetyl CoA: Acetyl CoA is formed when the pyruvate, from glycolysis, combines with Coenzyme A… tis takes place in the matrix.

18. Requirements for Krebs Cycle Pyruvic acid (3C acid) Coenzyme A 3 NAD + 1 ADP 1 FAD Double this list for each glucose.

21. Products of Krebs Cycle 3 CO 2 Acetyl CoA 3 NADH 1 ATP 1 FADH 2 Double this list for each glucose.

22. Krebs Cycle Produces most of the cell's energy in the form of NADH and FADH 2 … not ATP Does NOT require O 2 The CO 2 produced by the Krebs cycle is the CO 2 animal exhale when they breathe.

23. Oxidative Phosphorylation Process of extracting to energy from NADH and FADH 2 to form ATP. Function: Convert NADH and FADH 2 into ATP. Location: Mitochondria cristae.

24. Oxidative Phosphorylation NADH or FADH 2 ADP O 2

25. Oxidative Phosphorylation Requires the Electron Transport Chain… the Electron Transport Chain is a collection of proteins, embedded in the inner membrane, used to transport the electrons from NADH and FADH 2

26. Cytochrome c Cytochrome c: is one of the proteins of the electron transport chain… often used by geneticists to determine relatedness… exists in all living organisms. The Cytochromes alternate between RED and OX forms and pass electrons down to O 2

28. ATP Yield Each NADH energizes 3 ATP Each FADH 2 energizes 2 ATP

29. Chemiosmotic Hypothesis ETC energy is used to move H + (protons) across the cristae membrane. ATP is generated as the H + diffuse back into the matrix through ATP Synthase

31. ATP Synthase Uses the flow of H + to make ATP. Works like an ion pump in reverse, or like a waterwheel under the flow of H + “water”.

33. Alcoholic Fermentation Carried out by yeast, a kind of fungus.

35. Alcoholic Fermentation Uses only Glycolysis. An incomplete oxidation - energy is still left in the products (alcohol). Does NOT require O 2 Produces ATP when O 2 is not available.

37. Lactic Acid Fermentation Uses only Glycolysis. An incomplete oxidation - energy is still left in the products (lactic acid). Does NOT require O 2 Produces ATP when O 2 is not available.

39. Lactic Acid Fermentation Done by human muscle cells under oxygen debt. Lactic Acid is a toxin and causes soreness and stiffness in muscles.

40. Fermentation - Summary Way of using up NADH so Glycolysis can still run. Provides ATP to a cell even when O 2 is absent.

42. Aerobic vs Anaerobic Aerobic - Respiration with O 2 Anaerobic - Respiration without O 2 Aerobic - All three Respiration steps. Anaerobic - Glycolysis only.

43. Strict vs. Facultative Respiration Strict - can only carry out Respiration one way… aerobic or anaerobic. Facultative - can switch respiration types depending on O 2 availability. Ex - yeast

44. ATP yields by Respiration type Anaerobic - Glycolysis only Gets 2 ATPs per glucose. Aerobic - Glycolysis, Krebs, and Oxidative Phosphorylation (electron transport chain) Generates many more ATPs per glucose.

45. Aerobic ATP yield Glycolysis - 2 ATPS, 2 NADHs Krebs - 2 ATPS, 8 NADHs, 2 FADH 2 Each NADH = 3 ATP Each FADH 2 = 2 ATP

46. ATP Sum 10 NADH x 3 = 30 ATPs 2 FADH 2 x 2 = 4 ATPs 2 ATPs (Gly) = 2 ATPs 2 ATPs (Krebs) = 2 ATPs Max = 38 ATPs per glucose

47. However... Some energy is used in shuttling the NADH from Glycolysis into the mitochondria. Actual ATP yield ~ 36/glucose

48. Yeast Would rather do aerobic Respiration; it has 18x more energy per glucose. But, anaerobic will keep you alive if oxygen is not present.

49. Importance of fermentation Alcohol Industry - almost every society has a fermented beverage. Baking Industry - many breads use yeast to provide bubbles to raise the dough.

50. Summary Know the 3 main reactions of Respiration and the 4 required items for each.