PLB 115 1st Edition Lecture 9Previous Notes’ OutlineI. Lungs a. Functions, componentsII. Capillaries & AlveoliIII. Problems with lung functionDigestive SystemI. Mechanical & Chemical processinga. Mouthb. Stomachc. Small intestineII. PancreasIII. LiverIV. Large intestineV. Nutrient uptakeVI. LiverCurrent Notes’ OutlineI. Cell RespirationII. Aerobic RespirationIII. Glucose oxidationIV. GlycolysisV. Kreb’s CycleVI. Electron-Transport System VII. Metabolization of other MoleculesVIII. Fat RespirationIX. Protein RespirationX. Anaerobic Cellular RespirationXI. Alcoholic FermentationXII. Lactic Acid FermentationCell Respiration- Organisms are classified based on the kind of energy they useo Autotroph: Use sunlight’s energy to make organic molecules (sugar) & use this to make ATP. Photosynthesis: use the sunlight to make organic moleculesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.o Heterotroph: Get organic molecules from consuming autotrophs or other heterotrophs. Use energy from these to make ATP.ALL organisms: Use cellular respiration to harvest energy from organic molecules to make ATPAerobic Respiration: Several enzyme-controlled reactions- Oxygen oxidizes glucose- Glucose is oxidized to form carbon dioxide- Oxygen reduced to waterOxidizing Glucose- C-H & O-H bonds broken, electrons transferred to electron carriers, NAD, and FADo Electrons passed though electron transport chain & energy from electrons used to pump protons & energy from proton diffusion used to make ATPGlycolysis- Breakdown of glucose to pyruvic acid- Happens in cytoplasm- 2 ATP molecules energize glucose o Make 4 ATP 4 ATP- 2 ATP used Reduce 2 NAD+ to make 2 NADH Kreb’s Cycle: Citric Acid Cycle, tricarboxylic acid (TCA) cycleOccurs in mitochondrial matrix Breakdown of pyruvic acid  Released as carbon dioxide1 pyruvic acid molecule metabolized & make 1 ATP Reduce 4 NAD+ to 4 NADH Reduce 1 FAD to form 1 FADH2Electron-Transport System NADH and FADH2 release received electrons to electron transport chain (ETC) Proteins of ETC transfer electrons & use energy released to pump protons from matrix tointermembrane space, creating concentration gradient Accumulated protons diffuse back into the matrix through ATP synthaseo Energy released from here fuels ATP formation Oxygen accepts electrons (final acceptor), combines with protons, & becomes waterMetabolization of other Molecules Carb energy used firsto Complex carbohydrates metabolized into simple sugarsBUT Cells can use fats & protein energy tooo Fats converted to fatty acids & glycerol Glycerol to glyceraldehyde-3-phosphateo Proteins to amino acids Cells must reduce fats & proteins to be small enough to enter & be metabolized by enzymes of glycolysis or Kreb’s cycleFat Respiration Fats are broken down into glycerol & fatty acids  Glycerol converted to glyceraldehyde-3-phosphate o Enter glycolysis Fatty acids converted to acetyl CoA o Enter Kreb’s cycle  Fat molecules fuel formation of more ATP than glucoseo Good energy storage moleculeProtein Respiration Proteins converted to amino acids  Amino acid groups removedo Make keto acid (acetic acid, pyruvic acid, etc.) Enter Kreb’s cycleRECAPCarbohydrates, fats, and proteins can all be used for energyGlycolysis and the Kreb’s cycle allow thisMore calories consumed than used & excess food will be converted to and stored as fat Anaerobic Cellular Respiration (Plants) Metabolize glucose when do not have oxygeno Incomplete oxidation of glucose o Fermentation = anaerobic pathway using organic molecule as the final electron acceptorAlcoholic Fermentation (Fermented Yeasts (leavened bread= BEER!) Glycolysis beginso Pyruvic acid forms to ethanol Carbon dioxide released Lactic Acid Fermentation Glycolysis begins Pyruvic acid is reduced & forms lactic acido Explains why muscle cells can survive oxygen deprivation, unlike brain cells Muscle cells can do this b/c it has necessary enzymes, unlike brain cells- Lactic acid “burns” in