2. Chapter 4 Cellular Respiration GCA Mr. Cobb

3. Cellular respiration Food (glucose) into ATP Not “breathing” It can be either aerobic or anaerobic Aerobic – require oxygen Anaerobic – does not require oxygen

4. 3 Stages of Aerobic Cellular Respiration Glycolysis Preparation Step & Citric Acid Cycle (Kreb’s Cycle) Electron Transport

5. Glycolysis 1 st step in aerobic or anaerobic Location: cytoplasm of cell Glucose 2 Pyruvic Acid molecules This process does not require Oxygen. Total energy made is 4 ATP, but 2 is needed to start the rxn. 2 ATP is extra. What is made? 2 NADPH, 2 ATP, 2 Pyruvic Acids

6. Glycolysis glucose  pyruvate

8. Glycolysis GlucosePyruvic acid Pyruvic Acid

9. Aerobic O 2 required Release H 2 O and CO 2 and energy Remember that cellular respiration is the opposite of photosynthesis. C 6 H 12 0 6 + 6 O 2 6 CO 2 + 6 H 2 O + ATP

10. Aerobic Respiration Glycolysis is 1 st step and in both aerobic or anaerobic respiration 2 Steps in Aerobic Respiration: 2. Citric Acid Cycle or Krebs Cycle 3. Hydrogen and Electron Transport System

11. Cellular Respiration Flowchart (aerobic) Glucose (C 6 H 12 0 6 ) + Oxygen (0 2 ) Glycolysis Krebs Cycle Electron Transport Chain Carbon Dioxide (CO 2 ) + Water (H 2 O) + ATP

12. Citric Acid Cycle (Krebs) 2 Pyruvic acids from glycolysis diffuses into the mitochondria. Pyruvic acid is turned into acetyl CoA and CO 2 is released. One glucose molecule makes the cycle turn twice Chemical rxns in Mitochondria Products: 6 NADH, 2 FADH 2, 2 ATP and 4 CO 2

13. Krebs cycle pyruvate  acetyl CoA & CO 2

14. Citric Acid Production The Krebs Cycle Section 9-2 Mitochondrion

15. H+ and e- transport molecules: 1) NADH 2)FADH 2 

16. Electron Transport NADH and FADH 2 from Krebs Cycle are pumped by electron energy across the inner membrane (cristae) and creates a concentration difference. The H ions come back across through the ATP synthase and create ATP. Oxygen (from what we breathe in) comes in and binds to the H ions to make water.

17. Electron Transport 32 ATP Water is made from the Hydrogen and Oxygen.

20. Electron Transport Mitochondria * two membranes - outer - inner (folded)

21. Animation http://www.science.smith.edu/departments/Biology/Bio2 31/krebs.html

22. ELECTRON TRANSPORT CHAIN

23. matrix H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ Mitochondria H+H+H+H+ H+H+H+H+ NADH H+H+H+H+ FADH 2 e-e- H+H+H+H+ H+H+H+H+ e-e- H+H+H+H+

24. Electrons * passed across inner membrane * their energy gradually decreases H + * energy used to transport H + into the intermembrane space.Oxygen * the final electron acceptor H + H 2 O. * joins with H + to produce H 2 O. If there is no oxygen, the electron chain stops. because there is no way to release electrons. electrons

25. matrix H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ H+H+H+H+ Mitochondria H+H+H+H+ H+H+H+H+ NADH H+H+H+H+ FADH 2 e-e- H+H+H+H+ H+H+H+H+ e-e- H+H+H+H+

26. What happens when there is no oxygen to accept the electrons? * glycolysis done * then fermentation in cytoplasm 2 kinds 1)lactic acid 2)ethanol

27. 26 Products of Fermentation

28. fermentation 0 ATP Just takes e-& H+ off NADH so glycolysis can continue

29. Alcoholic Fermentation After glucose broken down to pyruvate, then pyruvate broken down to CO 2 and ETHANOL.

31. Alcoholic Fermentation by bacteria & yeast used to make bread, alcohol,

33. Lactic Acid fermentation By human muscle cells & bacteria Used to make cheese, yogurt, sour kraut

34. If you work anaerobically, fermentation occurs in your muscles lactic acid builds up results in muscle soreness