Complex Organic Molecules

1. Simpler waste Products w/ Less Energy Complex Organic Molecules Catabolic pathways Energy ENERGY For work Lost as heat

2. Example is Cellular Respiration

3. “oxidation of glucose” ?????? Lose electrons = Oxidized (LEO) Gain electrons = Reduced (GER) Oxidation / Reduction reactions or Redox reactions have to occur in pairs Electrons move toward the more electronegative atoms Oxygen is most common electron acceptor

4. -NAD+ is a coenzyme -is found in all cells -helps transfer electrons

5. Overview of respiration -glucose is oxidized -electrons (hydrogen atoms) leave the carbon atoms and combine w/ O2 -this happens by a series of steps via NAD+ and an electron transport chain -During this process ATP is produced

6. Two ways to get ATP Oxidative phosphorylation 1 ATP production that is coupled to the exergonic transfer of electrons from food to oxygen

8. 2 Substrate level phosphorylation ATP production by direct enzymatic transfer of phosphate from an intermediate substrate to ADP

11. Glycolysis overview -glucose (contain 6 Carbons) is split into two 3-carbon sugars. -these 3-carbon sugars are oxidized and rearranged to form 2 pyruvate molecules -occurs in the cytosol -no CO2 released -occurs whether or not oxygen is present. -2 net ATP produced

17. Glycolysis Animation

28. Figure 7.UN09 Oxidative phosphorylation: electron transport and chemiosmosis Citric acid cycle Pyruvate oxidation Glycolysis ATP ATP ATP

29. Figure 7.12 NADH 50 e− 2 NAD FADH2 Multiprotein complexes e− 2 FAD I 40 FMN II Fe•S Fe•S Q III Cyt b Fe•S 30 Cyt c1 IV Free energy (G) relative to O2 (kcal/mol) Cyt c Cyt a Cyt a3 20 e− 2 10 (originally from NADH or FADH2) 2 H ½ O2 0 H2O

30. Figure 7.14 2 1 H H Protein complex of electron carriers H H Cyt c IV Q III I ATP synthase II 2 H  ½ O2 H2O FAD FADH2 NAD NADH ATP ADP  P i (carrying electrons from food) H Electron transport chain Chemiosmosis Oxidative phosphorylation

31. Figure 7.13 H INTERMEMBRANE SPACE Stator Rotor Internal rod Catalytic knob ADP  ATP P MITOCHONDRIAL MATRIX i

32. animation http://www.sumanasinc.com/webcontent/animations/content/atpsynthase.html

33. Figure 7.15 Electron shuttles span membrane MITOCHONDRION 2 NADH CYTOSOL or 2 FADH2 2 NADH 6 NADH 2 FADH2 2 NADH Oxidative phosphorylation: electron transport and chemiosmosis Glycolysis Pyruvate oxidation 2 Acetyl CoA Citric acid cycle 2 Pyruvate Glucose  2 ATP  about 26 or 28 ATP  2 ATP About 30 or 32 ATP Maximum per glucose:

34. Brown Fat in hibernating animals Contain uncoupling protein that is a channel protein that allows diffusion of H+ NOT through ATP synthase

35. Comparison of chemiosmosis in chloroplasts and mitochondria SIMILARITIES An ETC in a membrane transports protons across a membrane ATP synthase in membrane couples diffusion of protons with phosphorylation of ADP ATP synthase and electron carriers (cytochromes) are very similar in both

37. DIFFERENCES ETC -mito transfer chemical E from food to ATP -electrons are extracted from oxidation of food molecules -chloroplasts transform light E into chemical E -uses light E to drive electrons to top of transport chain SPACIAL ORGANIZATION -mito pump protons from matrix out to the intermembrane space (which is a reservoir for protons) -chloro. Thylakoid membrane pumps protons from stroma into thylakoid compartment (serve as a proton reservoir)

38. Fermentation