24NutritionUSDA Food Guide PyramidSlide 4CarbohydratesSlide 6Slide 7LipidsSlide 9Slide 10Lipids: Dietary RequirementsProteinsSlide 13Proteins: Synthesis and HydrolysisSlide 15Essential Amino AcidsVitaminsSlide 18MineralsSlide 20MetabolismSlide 22Stages of MetabolismPowerPoint PresentationOxidation-Reduction (Redox) ReactionsMechanisms of ATP Synthesis: Substrate-Level PhosphorylationMechanisms of ATP Synthesis: Oxidative PhosphorylationSlide 28Slide 29Carbohydrate MetabolismCarbohydrate CatabolismGlycolysisSlide 33Slide 34Slide 35Slide 36Slide 37Slide 38Slide 39Slide 40Glycolysis: Phase 1 and 2Glycolysis: Phase 3Slide 43Krebs Cycle: Preparatory StepSlide 45Slide 46Krebs CycleSlide 48Slide 49Slide 50Slide 51Slide 52Slide 53Slide 54Slide 55Slide 56Slide 57Electron Transport ChainMechanism of Oxidative PhosphorylationSlide 60Slide 61Slide 62Slide 63Slide 64Slide 65Slide 66Slide 67Electronic Energy GradientSlide 69Slide 70ATP SynthaseStructure of ATP SynthaseSummary of ATP ProductionGlycogenesis and GlycogenolysisGluconeogenesisLipid MetabolismSlide 77Slide 78Slide 79Slide 80Lipogenesis and LipolysisSlide 82Slide 83Lipid Metabolism: Synthesis of Structural MaterialsSlide 85Protein MetabolismSlide 87Amino Acid OxidationCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsHuman Anatomy & PhysiologySEVENTH EDITIONElaine N. MariebKatja HoehnPowerPoint® Lecture Slides prepared by Vince Austin, Bluegrass Technical and Community CollegeC H A P T E R24Nutrition, Metabolism, and Body Temperature RegulationP A R T ACopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsNutritionNutrient – a substance that promotes normal growth, maintenance, and repairMajor nutrients – carbohydrates, lipids, and proteinsOther nutrients – vitamins and minerals (and technically speaking, water)Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsUSDA Food Guide PyramidFigure 24.1aCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsNutritionFigure 24.1bCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsCarbohydratesComplex carbohydrates (starches) are found in bread, cereal, flour, pasta, nuts, and potatoes Simple carbohydrates (sugars) are found in soft drinks, candy, fruit, and ice creamCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsCarbohydratesGlucose is the molecule ultimately used by body cells to make ATPNeurons and RBCs rely almost entirely upon glucose to supply their energy needsExcess glucose is converted to glycogen or fat and storedCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsCarbohydratesThe minimum amount of carbohydrates needed to maintain adequate blood glucose levels is 100 grams per dayStarchy foods and milk have nutrients such as vitamins and minerals in addition to complex carbohydratesRefined carbohydrate foods (candy and soft drinks) provide energy sources only and are referred to as “empty calories”Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsLipidsThe most abundant dietary lipids, triglycerides, are found in both animal and plant foodsEssential fatty acids – linoleic and linolenic acid, found in most vegetables, must be ingestedDietary fats: Help the body to absorb vitaminsAre a major energy fuel of hepatocytes and skeletal muscleAre a component of myelin sheaths and all cell membranesCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsLipidsFatty deposits in adipose tissue provide:A protective cushion around body organsAn insulating layer beneath the skinAn easy-to-store concentrated source of energyCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsLipidsProstaglandins function in:Smooth muscle contractionControl of blood pressureInflammationCholesterol stabilizes membranes and is a precursor of bile salts and steroid hormonesCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsLipids: Dietary RequirementsHigher for infants and children than for adultsThe American Heart Association suggests that:Fats should represent less than 30% of one’s total caloric intakeSaturated fats should be limited to 10% or less of one’s total fat intakeDaily cholesterol intake should not exceed 200 mgCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsProteinsComplete proteins that meet all the body’s amino acid needs are found in eggs, milk, milk products, meat, and fishIncomplete proteins are found in legumes, nuts, seeds, grains, and vegetablesCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsProteinsProteins supply:Essential amino acids, the building blocks for nonessential amino acidsNitrogen for nonprotein nitrogen-containing substancesDaily intake should be approximately 0.8g/kg of body weightCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsProteins: Synthesis and HydrolysisAll-or-none ruleAll amino acids needed must be present at the same time for protein synthesis to occurAdequacy of caloric intakeProtein will be used as fuel if there is insufficient carbohydrate or fat availableCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsProteins: Synthesis and HydrolysisNitrogen balanceThe rate of protein synthesis equals the rate of breakdown and lossPositive – synthesis exceeds breakdown (normal in children and tissue repair)Negative – breakdown exceeds synthesis (e.g., stress, burns, infection, or injury)Hormonal controlAnabolic hormones accelerate protein synthesisCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsEssential Amino AcidsFigure 24.2Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsVitaminsOrganic compounds needed for growth and good healthThey are crucial in helping the body use nutrients and often function as coenzymesOnly vitamins D, K, and B are synthesized in the body; all others must be ingestedWater-soluble vitamins (B-complex and C) are absorbed in the gastrointestinal tract B12 additionally requires gastric intrinsic factor to be absorbedCopyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsVitaminsFat-soluble vitamins (A, D, E, and K) bind to ingested lipids and are absorbed with their