1. Respiration

2. Respiration Respiration the process by which food molecules are broken down –Food molecules are 6-carbons sugars –You take in food which is digested and broken down into 6-carbon sugars –Plants can’t “eat” so they make 6-carbon sugars with photosynthesis –Mitochondria then transform the “food energy” into chemical energy

3. Respiration A 6-carbon sugar contains an enormous amount of energy (for a cell) Mitochondria “make change” energetically Take the energy in a sugar and convert it into more conveniently-sized packages

4. Respiration C 6 H 12 O 6 + 6O 2 → 6CO 2 + 6H 2 O + energy Carbon dioxide WaterCarbohydrateOxygen

5. Respiration Aerobic respiration: processes that require oxygen in order to take place Anaerobic respiration: processes that do not require oxygen

6. Aerobic Respiration Step 1: Glycolysis Step 2: Breakdown of pyruvic acid Step 3: Citric acid cycle Step 4: Electron transport chain

7. Respiration MATRIX: Breakdown of pyruvic acid, Citric acid cycle INNER MEMBRANE: Electron transport chain Outer membrane CYTOPLASM: Glycolysis

8. Step 1: Glycolysis Occurs in cytoplasm Does not require oxygen Involves splitting a glucose (6-carbon sugar) into 2 3-carbon molecules: pyruvic acid

9. Step 1: Glycolysis Also produces H + ions and energizes electrons which are captured by NAD +, forming NADH + H +

10. Step 1: Glycolysis Glucose

11. Step 1: Glycolysis Glucose 2 ATP2 ADP

12. Step 1: Glycolysis Glucose 2 ATP2 ADP P P 2 PGAL

13. Step 1: Glycolysis Glucose 2 ATP2 ADP P P 2 PGAL 4ADP + 4 P i 2 NAD + 2NADH + 2H + 4ATP

14. Step 1: Glycolysis Glucose 2 ATP2 ADP P P 2 PGAL 4ADP + 4 P i 2 NAD + 2NADH + 2H + 4ATP 2 Pyruvic acid

15. Step 1: Glycolysis Net yeild –2 ATP (uses 2, produces 4) –2 NADH –2 pyruvic acid

16. Aerobic Respiration Step 1: Glycolysis Step 2: Breakdown of pyruvic acid Step 3: Citric acid cycle Step 4: Electron transport chain

17. Step 2: Breakdown of Pyruvic Acid Occurs when pyruvic acid (from glycolysis) enters the mitochondrial matrix Requires oxygen –If there is no oxygen present pyruvic acid enters fermentation

18. Step 2: Breakdown of Pyruvic Acid Involves breaking CO 2 off pyruvic acid Remaining portion of pyruvic acid combines with coenzyme A to form acetyl- CoA

19. Step 2: Breakdown of Pyruvic Acid Also produces H + and energizes electrons which are captured by NAD +, to form NADH + H +

20. Step 2: Breakdown of Pyruvic Acid To citric acid cycle Mitochondrial membrane “Exhaled”

21. Step 2: Breakdown of Pyruvic Acid Net yeild –2 NADH –Acetyl-CoA

22. Aerobic Respiration Step 1: Glycolysis Step 2: Breakdown of pyruvic acid Step 3: Citric acid cycle Step 4: Electron transport chain

23. Step 3: Citric Acid Cycle Occurs in mitochondrial matrix Acetyl-CoA is transformed into citric acid through a series of reactions

24. Step 3: Citric Acid Cycle More ATP and CO 2 are produced More H + are produced and electrons are energized NAD + and FAD capture them to form NADH + H + and FADH

25. Step 3: Citric Acid Cycle CITRIC ACID CYCLE 4C 5C 6C – Citric acid

26. Step 3: Citric Acid Cycle Net yield –2 ATP –6 NADH –2 FADH 2

27. Aerobic Respiration Step 1: Glycolysis Step 2: Breakdown of pyruvic acid Step 3: Citric acid cycle Step 4: Electron transport chain

28. Step 4: Electron Transport Chain Happens on inner membrane of mitochondria Occurs only if oxygen is present –Oxygen is final electron acceptor –If no oxygen is present reaction stops

29. Step 4: Electron Transport Chain Electrons come from NADH and FADH molecules which gathered them during glycolysis and CTA Energy from electrons is used to add P i to ADP, forming ATP At the end of the chain, oxygen accepts the electrons and combines with 2 H + ions to form water

30. Step 4: Electron Transport Chain Inner mitochondrial membrane Outer mitochondrial membrane Electron transport chain Cytochromes Inter- membrane space Cytochromes

31. Step 4: Electron Transport Chain Net yeild –32 ATP

32. Aerobic Respiration Step 1: Glycolysis Step 2: Breakdown of pyruvic acid Step 3: Citric acid cycle Step 4: Electron transport chain

33. Aerobic Respiration Glycolysis 2 ATP Citric acid cycle 2 Electron transport chain**32 ATP **Makes ATP from electrons carried to it from the first 3 steps

34. Aerobic Respiration Makes 36 ATP

35. Anaerobic Respiration Pyruvic acid molecules are still formed through glycolysis Broken down differently: –No ATP is produced after glycolysis –NAD + is regenerated so glycolysis can continue

36. Anaerobic Respiration 2 types: –Lactic acid fermentation –Alcoholic fermentation

37. Lactic Acid Fermentation Lactic acid is end product Occurs when muscles require energy at a faster rate than it can be supplied through aerobic respiration Causes burning sensation in muscles

38. Lactic Acid Fermentation Glycolysis

39. Lactic Acid Fermentation

40. Net yield –2 ATP

41. Alcoholic Fermentation Ethyl alcohol and CO 2 are end products Occurs in organisms that live in environments lacking oxygen Source of bubbles in beer and champagne and causes baking bread to rise

42. Alcoholic Fermentation Glycolysis

43. Alcoholic Fermentation Glycolysis 2 Ethanol 2 CO 2

44. Comparison of Aerobic Respriation and Fermentation How many ATP does aerobic respiration produce? How many ATP does fermentation produce? 36 ATP 2 ATP

45. WE’RE DONE!!!!

46. Step 1: Glycolysis Glucose 2 ATP2 ADP P P 2 PGAL 4ADP + 4 P i 2 NAD + 2 Pyruvic acid

47. Step 2: Breakdown of Pyruvic Acid To citric acid cycle “Exhaled”

48. Step 3: Citric Acid Cycle CITRIC ACID CYCLE 4C 5C 6C – Citric acid 4C

49. Step 4: Electron Transport Chain Inner mitochondrial membrane Outer mitochondrial membrane Electron transport chain Cytochromes Inter- membrane space Cytochromes

50. Lactic Acid Fermentation Glycolysis

51. Alcoholic Fermentation Glycolysis 2 Ethanol 2 CO 2