2.  The summary equation of cellular respiration.  The difference between fermentation and cellular respiration.  The role of glycolysis in oxidizing glucose to two molecules of pyruvate.  The process that brings pyruvate from the cytosol into the mitochondria and introduces it into the citric acid cycle.  How the process of chemiosmosis utilizes the electrons from NADH and FADH 2 to produce ATP.

3. E flows into ecosystem as Sunlight Autotrophs transform it into chemical E O 2 released as byproduct Cells use some of chemical E in organic molecules to make ATP E leaves as heat

4. Complex organic molecules Simpler waste products with less E Some E used to do work and dissipated as heat Catabolic Pathway

5. Respiration: exergonic (releases E) C 6 H 12 O 6 + 6O 2  6H 2 O + 6CO 2 + ATP (+ heat) Photosynthesis: endergonic (requires E) 6H 2 O + 6CO 2 + Light  C 6 H 12 O 6 + 6O 2

6. Xe - + Y  X + Ye -  Oxidation = lose e -  Reduction = gain e - C 6 H 12 O 6 + 6O 2  6H 2 O + 6CO 2 + oxidation reduction oxidation (donor) lose e - reduction (acceptor) gain e - ATP OiLRiG or LeoGer

8.  Energy is released as electrons “fall” from organic molecules to O 2  Broken down into steps: Food (Glucose)  NADH  ETC  O 2  Coenzyme NAD + = electron acceptor  NAD + picks up 2e - and 2H +  NADH (stores E)  NADH carries electrons to the electron transport chain (ETC)  ETC: transfers e - to O 2 to make H 2 O ; releases energy

11.  Generate small amount of ATP  Phosphorylation: enzyme transfers a phosphate to other compounds  ADP + P i  ATP P compound

12. 1.Glycolysis 2.Pyruvate Oxidation + Citric Acid Cycle (Krebs Cycle) 3.Oxidative Phosphorylation (electron transport chain (ETC) & chemiosmosis)

14. Cellular Respiration

15.  “sugar splitting”  Believed to be ancient (early prokaryotes - no O 2 available)  Occurs in cytosol  Partially oxidizes glucose (6C) to 2 pyruvates (3C)  Net gain: 2 ATP + 2NADH  Also makes 2H 2 O  No O 2 required

16. Stage 1: Energy Investment Stage  Cell uses ATP to phosphorylate compounds of glucose Stage 2: Energy Payoff Stage  Two 3-C compounds oxidized  For each glucose molecule:  2 Net ATP produced by substrate-level phosphorylation  2 molecules of NAD +  NADH

18. glucose 2 pyruvate P ADP 2 ATP 2 NAD + 2 NADH 2 NADH + 2H + (3-C) C 3 H 6 O 3 2H 2 O

19. Citric Acid Cycle (matrix) Citric Acid Cycle (matrix) ETC (inner membrane) ETC (inner membrane)

20. Cellular Respiration

22.  Pyruvate  Acetyl CoA (used to make citrate)  CO 2 and NADH produced

23.  Occurs in mitochondrial matrix  Acetyl CoA  Citrate   Net gain: 2 ATP, 6 NADH, 2 FADH 2 (electron carrier)  ATP produced by substrate-level phosphorylation CO 2

26. Cellular Respiration

27. http://multimedia.mcb.harvard.edu/anim_mitochondria.html

28. ELECTRON TRANSPORT CHAIN  Occurs in inner membrane of mitochondria  Produces 26-28 ATP by oxidative phosphorylation via chemiosmosis CHEMIOSMOSIS  H + ions pumped across inner mitochondrial membrane  H + diffuse through ATP synthase (ADP  ATP)

29.  Collection of molecules embedded in inner membrane of mitochondria  Tightly bound protein + non- protein components  Alternate between reduced/oxidized states as accept/donate e -  Does not make ATP directly  Ease fall of e- from food to O 2  2H + + ½ O 2  H 2 O

31.  Chemiosmosis = H + gradient across membrane drives cellular work  Proton-motive force: use proton (H + ) gradient to perform work  ATP synthase: enzyme that makes ATP  Use E from proton (H + ) gradient – flow of H + back across membrane

34. e- passed down E levels oxidative phosphorylation chemiosmosis ATP ETC O 2  H 2 O proton gradient proton motive force H+H+ redox reactions ATP synthase uses uses E of in which to final e- acceptor generates which couples called drives through to produce H+ pumped from matrix to intermembrane space

36.  Anaerobic Respiration: generate ATP using other electron acceptors besides O 2  Final e - acceptors: sulfate (SO 4 ), nitrate, sulfur (produces H 2 S) Obligate anaerobes  Eg. Obligate anaerobes: can’t survive in O 2  Facultative anaerobes  Facultative anaerobes: make ATP by aerobic respiration (with O 2 present) or switch to fermentation (no O 2 available)  Eg. human muscle cells

38. FERMENTATION  Keep glycolysis going by regenerating NAD +  Occurs in cytosol  No oxygen needed  Creates ethanol [+ CO 2 ] or lactate  2 ATP (from glycolysis) RESPIRATION  Release E from breakdown of food with O 2  Occurs in mitochondria  O 2 required (final electron acceptor)  Produces CO 2, H 2 O and up to 32 ATP O 2 presentWithout O 2

39. ALCOHOLIC FERMENTATION  Pyruvate  Ethanol + CO 2  Ex. bacteria, yeast  Used in brewing, winemaking, baking LACTIC ACID FERMENTATION  Pyruvate  Lactate  Ex. fungi, bacteria, human muscle cells  Used to make cheese, yogurt, acetone, methanol  Note: Lactate build-up does NOT cause muscle fatigue and pain (old idea)

40.  Carbohydrates, fats and proteins can ALL be used as fuel for cellular respiration  Monomers enter glycolysis or citric acid cycle at different points

41.  Allosteric enzyme that controls rate of glycolysis and citric acid cycle  Inhibited by ATP, citrate  Stimulated by AMP  AMP+ P + P  ATP

43. pyruvate oxidation ENERGY glycolysis (cytosol) glycolysis (cytosol) ethanol + CO 2 (yeast, some bacteria) ethanol + CO 2 (yeast, some bacteria) anaerobic (without O 2 ) aerobic cellular respiration (with O 2 ) lactic acid (animals) lactic acid (animals) ETC chemiosmosis oxidative phosphorylation citric acid cycle mitochondria Fermentation (cytosol) Fermentation (cytosol)

45. Electron Transport ChainChemiosmosis