2. 1 1 11/3/2015 Cellular Respiration Filename: Respire.ppt

3. 2 2 11/3/2015 Lecture Outline Using Chemical energy to drive metabolism Production of ATP Cellular respiration –Clycolysis –Krebs cycle –Electron transport –Chemiosmosis

4. 3 3 11/3/2015 Lecture Overview All organisms drive their metabolism with ATP generated from Rearrangement of chemical bonds Energetic electrons from proton pumps Electrons from photosynthesis Electrons from oxidation of sugars and fats

5. 4 4 11/3/2015 Background Terms & Concepts Glucose Chemiosmosis Oxidation- reduction ATP Exergonic vs endergonic reactions

6. 5 5 11/3/2015 Concepts from OAC Synthesis of ATP Glycolysis: Krebs cycle anaerobic vs aerobic glucose catabolism Energy from fats & proteins

7. 6 6 11/3/2015 Energy Flow & Recyling Energy Poor Energy Rich

8. 7 7 11/3/2015 Cellular Respiration Release of energy stored in organic compounds –Carbohydrate –Fats –Proteins (net energy loss) Oxygen is consumed as a reactant Carbon dioxide and water are byproducts Energy is used indirectly –trapped as ATP

9. 8 8 11/3/2015 Pathways in Cellular Respiration Glycolysis Krebs cycle Electron transport chain Cellular Respiration Cumulative function of three metabolic pathways and chemiosmosis

10. 9 9 11/3/2015 Catabolism of various foods

11. 10 11/3/2015 Overview of Cellular Respiration A room of your own... ATP

12. Glycolysis occurs whether or not oxygen is present

13. 12 11/3/2015 Glycolysis OCCURS in the CYTOPLASM Glucose (6 carbon sugar) >>> 2 pyruvate (3 carbon sugar) Energy investment phase Energy yielding phase Net yield of energy No Carbon dioxide is released during glycolysis

14. 13 11/3/2015 Electron Transport System

15. 14 11/3/2015 Glycolysis

16. 15 11/3/2015 Glycolysis: Energy Investment Glucose + ATP-> glucose-6-P + ADP – hexokinase Glucose-6-P -> Fructose-6-P –phosphoglucoisomerase Fructose-6-P + ATP -> Fructose 1,6, diphosphate + ADP –phosophofructokinase Fructose 1,6,diphosphate -> glyceraldehyde phosphate + dihydroxyacetone phosphate –aldolase

17. 16 11/3/2015 Energy Investment Phase

18. 17 11/3/2015 More ATP investment ATP Investment

19. 18 11/3/2015 Isomerization glyceraldehyde phosphate & dihydroxyacetone phosphate are isomers –Isomerase interconverts –glyceraldehyde phosphate removed next as next step THUS Equilibrium between the two sugars is in direction of glyceraldehyde phosphate

20. 19 11/3/2015 Glycolysis: Energy Yield Phase Glyceraldehyde-P + 2NAD+ +2Pi -> 1,3 glycerophosphate + 2 NADH + 2 H+ !,3 glycerophosphate + 2ADP -> 3 phosphoglycerate + 2 ATP Relocate phosphate group Remove water to create phosphoenolpyruvate Remove phosphate from PEP PEP + 2ADP -> pyruvate + 2ATP

21. 20 11/3/2015 The first payoff (substrate-level phosphorylation) Substrate level Phosphorylation

22. 21 11/3/2015 More dividends (substrate-level phosphorylation) More Energy Payoff

23. 22 11/3/2015 Glycolysis: Net Energy Yield Glucose >>> 2 pyruvate 2 ADP >>> 2 ATP 2 NAD+ >>> 2NADH NADH>>> electron transport chain if oxygen is present

24. 23 11/3/2015 Alternate Glycolytic Pathway Glycolysis Embden-Meyerhof Glucose>> glucose-6 phosphate Fructose-6 phosphate Fructose 1,6 diphosphate ISOMERS –dihydroxyacetone phosphate –Glyceraldehyde 3 P Alternate Enter-Doudoroff Glucose>> glucose-6 phosphate 6 phosphogluconic acid Keto deoxy 6 phoshogluconic acid pyruvic acid + Glyceraldehyde 3 P

25. 24 11/3/2015 Pyruvate Fermentation Oxidative phosphorylation

26. 25 11/3/2015 Role of Pyruvate

27. 26 11/3/2015 Formation of Acetyl CoA Pyruvate translocated from cytoplasm to mitochrondial matrix Pyruvate + NAD+ -> Acetate + NADH + CO2 Acetyl group attached to Coenzyme A Acetyl CoA links glycolysis to the Krebs cycle

28. 27 11/3/2015 Formation of Acetyl CoA

29. 28 11/3/2015 Krebs cycle oxidation of pyruvate generated by glycolysis –glucose->2 pyruvate Generates 1 molecule of ATP/ pyruvate –substrate level phosphorylation Generates 4 molecules of NADH / pyruvate Generates 1 molecule of FADH2/ pyruvate Generate 3 molecules of carbon dioxide OCCURS in MITOCHONDRIAL MATRIX occurs in prokaryotic cytoplasm

30. 29 11/3/2015 Krebs cycle

31. 30 11/3/2015 Summary of Krebs Cycle IN Out

32. 31 11/3/2015 Krebs Cycle Balance Sheet Input Water ADP NAD+ FAD+ Acetyl CoA Output Carbon Dioxide ATP NADH FADH