1. Cellular Respiration: Harvesting Chemical Energy Chapter 6

2. Energy Flow in Ecosystems Photosynthesis captures and store sunlight energy as glucose Cellular Respiration release energy to cell to do work.

3. Respiration is the complement to Photosynthesis, completing a cycle:

4. PHOTOSYNTHESIS AEROBIC RESPIRATION C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O SUNLIGHT Photosynthesis & Respiration The products of photosynthesis are the reactants for respiration

5. Controlled Uncontrolled

6. The Powerful Mitochondria Provide the cell with usable energy as ATP Cells with high energy demands make more mitochondria Muscle cells have very high number of mitochondria We breath to get oxygen to our mitochondria and to to rid ourselves of the carbon dioxide the mitochondria produce The blood carries these gasses to our lungs for gas exchange by diffusion The more energy you burn, the more you breath out

7. ATP : Cellular unit of energy ATP ADP + P i

8. C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O glucoseoxygen carbon dioxide water The Reaction for Respiration: The reverse of the equation for photosynthesis The carbon atoms we eat in glucose we breath out as carbon dioxide The oxygen we breath in becomes water in our bodies

9. Reactants and Products The carbon atoms we eat in glucose we breath out as carbon dioxide The oxygen we breath in becomes water in our bodies

11. Thought questions What cells have very high number of mitochondria ? Why do we breath? We breath to get _____ into our mitochondria and to get rid of the _______the mitochondria produce How do these gasses move in the body? How does your breathing relate to energy use?

12. GLUCOSE The common food molecule

13. Respiration is a three step process: In Cytoplasm: Step 1 Glycolysis –breaks glucose into 2 pyruvate molecules –Makes 2 ATP In Mitochondrion: Step 2 Krebs cycle –Completely breaks all c-c bonds –Primes the proton gradient –Makes 2 ATP Step 3 Electron transport chain –Makes ATP by chemiosmosis –Needs O 2 –Makes 32-34 more ATP

14. 3 Steps to Cellular respiration

15. Respiration is a controlled release of usable energy, in the form of ATP

16. Step 1: Glycolysis Breaks (C 6 ) glucose into 2 pyruvate (C 3 ) Breaks C-C bond Forms 2 NADH (high energy) Forms a net of 2 ATP per glucose Takes place in cytoplasm Must have 2 NAD + as reactants to run Does not release CO 2 or need Oxygen

17. glucose pyruvate animal cell (eukaryotic) plant cell (eukaryotic) bacterial cell (prokaryotic) GLYCOLYSIS All cells use Glycolysis even bacteria

18. Glycolysis: 2 ATP in for “Priming” 4 ATP out Net: 2 ATP

19. ATP formation by phosphate transfer Fuel Molecule with 2 P Now Fuel Molecule with 1 P P group transferred onto now a ATP

20. Energy tab so far: 1 Glucose: Glycolysis net: 2 ATP

21. 3 Steps to Cellular respiration

22. From the cytoplasm to the mitochondria Pyruvate moves into the mitochondrion Some preparatory steps from 2 NADH (a cofactor) Form here the products go to the Krebs Cycle

23. The Krebs Cycle Takes place in the inner most compartment of the mitochondria Breaks all C-C bonds, uses up all the remainders of glucose Releases CO 2 Carbon dioxide that you breath out Loads cofactors NADH, FADH 2 Forms 2 ATP

24. Krebs Cycle

25. Energy tab so far: 1 Glucose: Glycolysis net: 2 ATP Krebs Cycle: 2 ATP

26. 3 Steps to Cellular respiration

27. Electron Transport Chain Electron flow along inner membrane All cofactors (coenzymes) from Glycolysis, preparatory steps and Krebs go to inner membrane Cofactors release electrons, and protons Electrons flow and pump protons out creating gradient ATP made n by chemiosmosis Electrons flow to Oxygen, the final electron acceptor, and with protons form water

28. inner compartmentouter compartmentcytoplasm outer mitochondrial membrane inner mitochondrial membrane Mitochondrion Structure

29. OUTER COMPARTMENT INNER COMPARTMENT Electron transport chain Cofactors (NADH, FADH2) provide protons and fuel transport chain proton pump

30. Chemiosmosis by the proton gradient makes ATP from ADP + P i

31. Energy tab so far: 1 Glucose: Glycolysis net: 2 ATP Krebs Cycle: 2 ATP Chemiosmosis: (Electron transport chains): 32-34 ATP ----------------- Grand Total 34-36 ATP

32. Why we breath: We need Oxygen to accept electrons and keep the transport chain flowing We must get rid of the excess carbon dioxide from the Krebs cycle, or our blood pH will drop too low.

33. We need Oxygen to:

34. Foods other than glucose… Catabolism: all biomolecules are broken down and feed into the pathway at different points. –Lipids –Complex carbohydrates –Proteins –Nucleic Acids

35. All food feeds into Respiration:

36. Not all cells do aerobic respiration: Some live with out oxygen (anaerobes) Some need more energy faster than the Krebs cycle can keep up (muscles under workout stress) Some environments turn off the Krebs cycle (yeasts) Bacteria do not have mitochondria These cells do Fermentation

37. start (Glycolysis) in cytoplasm completed in mitochondrion start (Glycolysis) in cytoplasm completed in cytoplasm Aerobic Respiration In Mitochondria Anaerobic Energy- Fermentation Mitochondria require oxygen Fermentation does not

39. Fermentation equations:

40. Fermentation Normal Glycolysis, only 2 ATP No Krebs Cycle Must regenerate NAD + or Glycolysis will stop “wastes” pyruvate energy to reform NAD + Produces either Lactic Acid (Muscles) or Ethanol and Carbon Dioxide (Yeasts). NO additional ATP

41. Energy Comparison: Fermentation Glycolysis 2 ATP Total 2 ATP Aerobic Respiration Glycolysis 2 ATP Krebs Cycle 2 ATP ETC 32-34 ATP Total 26-38 ATP

43. Ethanol & Carbon Dioxide Production The carbon dioxide makes the bubbles in beer and champagne!! They let it escape in wine

44. Ethanol & Carbon Dioxide Fermentation The ethanol bakes away, it is part of the aroma of baking bread!!

45. Lactic Acid Production