CHAPTER 9—ENERGY METABOLISMMetabolism• Metabolism is the sum of all chemical and physical processes by which the body breaks down and builds up molecules• Chemical reactions require or release energy Chemical Reactions in the Bodyo Metabolic Pathway: group of biochemical reactions that occur in a progression from beginning to endo Intermediates: compounds formed in one of the many steps in a metabolic pathwayo Anabolic Pathway: build compounds, requires energyo Catabolic Pathway: breakdown compounds, release energyEnergy for the Cello Adenosine Triphosphate (ATP)• Body’s main source of NRG• Utilized directly by the cells• Hydrolysis of the high-energy phosphate bonds releases energy,creating ADP + free Po Adenosine Diphosphate (ADP)• Recycled back into ATP with theaddition of a free Po Adenosine Monophosphate (AMP)• Hydrolysis of ADPOxidation-Reduction Reactions• ATP synthesis depends on the transfer ofelectrons in a series of reactions from NRG yielding compounds to oxygen• Reactions occur together• Oxidized substance : loses electron(s); gains oxygen/loses hydrogen• Reduced substance : gains election(s); loses oxygen/gains hydrogen, enzymes control oxidation-reduction reactions, Vitamins act as coenzymes• The reduction of O to form water is vitalto synthesis of ATPOxidation vs Reduction• LEO the lion goes GER• OIL RIG• Oxidation is loss of electrons• Reduction is gain of electronsPenis• Gaining and oxygen =oxidation• Losing an oxygen=reductionMetabolic Pathways• Metabolic pathways are chemical reactions that occur sequentially to achieve a particular goalOccur in specific types of the cell, May be limited to specific organs or tissues• __________________ is the site of energy production in the cellCellular Respiration • The __________________ of obtaining energy in order to produce __________________ molecules Oxidation of food molecules to form ____________________________________ is the final electron acceptor• AerobicWith ____________________________________ • AnaerobicWith ____________________________________Aerobic Cellular Respiration of Glucose: 4 Staged (Figure 9-5)1. Glycolysis1 glucose is oxidized to 2 __________________, producing NADH + H+Occurs in the __________________Net _____ ATP2. Transition reactionCHAPTER 9—ENERGY METABOLISM__________________ is oxidized and joined with __________________ (_______), producing __________________and NADH + H+ an releasing CO2 as wasteOccurs in __________________3. Citric acid cycle (CAC)__________________enters producing NADH + H, FADH2 + D, ATP (GTP intermediate), and CO2 Occurs in __________________ Net _____ ATP (from GTP)4. Electron transport chain (ETC)NADH + H+, FADH2 oxidized to NAD+ and FADOccurs in __________________ At the end of ETC, __________________ is combined with H ions to form __________________Net _____ ATP (from NADH, FADH, and GTP)Most _______ formed in ETCMitochondria is the powerhouse of cellAnaerobic Metabolism (Anaerobic Glycolysis)• Occurs in cells with ____________________________________and in cells when there is limited ____________________________________ is converted to ____________________________________ is picked up by the liverLiver synthesizes compounds used in aerobic metabolismPyruvate, glucose, or other aerobic intermediatesNot as efficient as aerobic metabolismNet _____ ATPGlycolysis PathwayATP Production from Fats• LipolysisBreakdown of triglycerides à __________________ and __________________Free fatty acids are used for __________________ or ____________________________________ is converted to pyruvate, then to Acetyl-CoA for entry into the CACRegulated by hormone-sensitive lipase• Carnitine shuttles fatty acids from __________________ into __________________• Fatty acid oxidationFurther breakdown of __________________ for energy productionFatty Acid Oxidation (Beta-Oxidation)• Occurs in __________________• Cleaving of _____ carbons at a timeConverts into __________________16 C FA yields _____ net ATP vs6 C glucose yields _____ net ATP• Yields __________________, NADH +H+, and FADH2CHO Aids Fat Metabolism• __________________ needed to run CAC1 step in CAC: __________________ + __________________• Other intermediates produced via CAC enter different biosynthetic pathwaysThis slows CAC, which eventually leadsto insufficient __________________• __________________ can be convertedto __________________So as FA create __________________, the cells increase the ____________________________________to supply enough __________________Alternate Fat Metabolism: Ketogenesis • Ketone bodies formed by an __________________ fatty acid oxidation• Occurs mainly with hormonal imbalancesCHAPTER 9—ENERGY METABOLISME.g., inadequate insulin to balance glucagon• Build-up of __________________ bodies (ketosis)Some converted to __________________Some are excreted• KetosisIn Type 1 DiabetesIn semistarvation or fastingEnergy from Protein• The body prefers using carbohydrates and fats for energy• Protein is reserved for metabolic functions that cannot be performed by othersBuilding and repairing body tissues• Protein is used for fuel during __________________ total energy or low __________________ intakeProtein Metabolism• Primarily in the __________________Muscles metabolize only ____________________________________(leucine, isoleucine, and valine)• DeaminationLoss of the amine group from AALeft with a carbon skeletonRequires vitamin B-6Carbon skeleton is utilized Enter CAC as __________________Others form ____________________________________or __________________Protein Metabolism: Paths for the Carbon Skeleton • __________________ Amino AcidsContain Cs that __________________ become glucoseAny part of carbon skeleton that can form pyruvateOr bypass Acetyl-CoA synthesis and enter CAC directly• __________________ Amino AcidsContain Cs that __________________ become glucoseAny part of carbon skeleton that becomes Acetyl-CoA• Key between the two:Can part or all of carbon skeleton of AA yield a “new” oxaloacetate during metabolism? Because 2 are needed to form glucose• GluconeogenesisA metabolic pathway that results in the generation of __________________ from __________________ carbon substrates (such as pyruvate, lactate, glycerol, glucogenic, amino acids, and odd-chain fattyacids)Only in __________________ and certain kidney cellsBegins in mitochondria; returns to cytosol Requires B-vitamins and