Lecture Notes For Wardlaw's Contemporary Nutrition, 11th Edition

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CHAPTER 1NUTRITION, FOOD CHOICES, AND HEALTHOVERVIEWThis introductory chapter provides an overview of the study of nutrition.Nutrients and theirroles in the body are discussed.Energy and how it is measuredis described.Helpful math skillsused in the study of nutrition are reviewed. The scientific method is explained with particular focusgiven to its application in the study of nutrition.The typical North Americaneating patternispresented along with methods the government uses to monitor consumption. U.S. health objectivesincluded in Healthy People 2020 are briefly described. Recommendations for promoting healthybehaviors and lifestyles are also discussed.TheNutrition and Your Healthsection,“Eating Well inCollege,”investigates common nutritional concerns faced by college students, includingchoosingfoods,weight gain,alcohol and binge drinking,eating disorders,the vegetarian lifestyle,dietaryconcernsofstudent athletes, and tips for eating well on a budget.KEY TERMSAlcoholAmino acidAnimal modelAppetiteAtomBondCancerCarbohydrateCardiovascular diseaseCase-control studyCellChemical reactionChronicComplexcarbohydrateControl groupDiabetesDouble-blind studyElectrolyteEnzymeEpidemiologyEssential nutrientFat-solubleFiberGeneGenomicsGlucoseHungerHypertensionHypothesesInorganicKilocalorie (kcal)LipidMacronutrientMajor mineralMetabolismMicronutrientMineralNutrientObesityOsteoporosisPeer reviewPhytochemicalPlaceboProteinRegistered dietitian (RD)Registereddietitiannutritionist (RDN)Risk factorsSatietyScurvySimple sugarSolventStarchStrokeTheoryTracemineralVitaminWaterWater-solubleSTUDENT LEARNING OUTCOMESChapter 1 is designed to allow you to:1.1Describe how our foodchoicesare affected by the flavor, texture, and appearance offood; routines and habits; early experiences and customs; advertising; nutrition and health

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concerns; restaurants; social changes; economics; andphysiological processes affected bymeal size and composition.1.2Identifyeating patternand lifestyle factors that contribute to the 15 leading causes ofdeath in North America.1.3Define the termsnutrition,carbohydrate,protein,lipid (fat),alcohol,vitamin,mineral,water,phytochemical,kilocalorie (kcal),andfiber.1.4Determine the total calories (kcal) of a food oreating patternusing the weight and caloriecontent of the energy-yielding nutrients, convert English to metric units, and calculatepercentages, such as percent of calories from fat inan eating pattern.1.5Understand the scientific method as it is used informinghypotheses and theories in thefield of nutrition, includingthe determination of nutrient needs.1.6List the major characteristics of the North Americaneating patterns,the food habits thatoften need improvement, and the key“Nutrition and Weight Status” objectives of theHealthy People 2020report.1.7Describe a basic plan for health promotion and disease preventionand what to expectfrom good nutrition and a healthy lifestyle.1.8Identify food and nutrition issues relevant to college students.LECTURE OUTLINE1.1Why Do You Choose the FoodYou Eat?A.What influences yourfoodchoices?1.Food is more than nourishment.2.A mix of biological and social factors influencesyour food choices (see Figure1-1).a.Food flavor, texture,andappearance are the most important factors.b.Early exposure to various people, places,and eventsc.Routines and habitsd.Marketing and advertising bythe food industrye.Restaurant diningi.Larger portions,nutrient poor, andmore calorie dense than homecooked mealsii.Federal regulations require health information on menus of somerestaurants.f.Time and convenienceg.Cost and economicsi.Food cost issecondreason why people choosetheir foods.ii.Youngadults and those with higher incomes spend the most onfood.h.Nutritioni.Well-educated,middleclassprofessionalsmakemorehealth-related food choices.ii.A greater percentage of women read food labels than men.B.Why are yousohungry?1.Hunger is thephysiological (internal) drive to eat.

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2.Appetite is the psychological (external) influences thatencourageus to eat, oftenin absence of hunger.3.Satiety is the state in which there is no longer a desire to eat,a feeling ofsatisfaction.4.Thefeedingcenterandsatiety centerof the brain work to promote adequatenutrient intake.C.Putting our food choices into perspective1.Satiety regulation is not perfect.2.Decrease portion sizes slowly to allow the body (appetite and satiety) time toadjust.1.2How IsNutrition Connected to Good Health?A.What is nutrition?1.Science that links foodto health and disease2.Ingestion, digestion, absorption, transport, and excretion of food substancesB.Nutrients come from food1.Nutrients are substances found in food that provide energy and are vital forgrowth and maintenance of body.2.An essential nutrient is required by the body to meet its needs. The bodycannot produce it, or produces it in too little quantity to meet its needs.3.Essentialnutrients must satisfy three criteria.a.One specific biological function of thenutrientmust be identifiedinthe body.b.Omission of the nutrientmust leadto decline in biological functions.c.Replacing the omitted nutrient before permanent damage occursrestores normal biological functions.C.Why study nutrition?1.Pooreating patternsandasedentary lifestyle are risk factorsfor life-threateningchronic diseases (see Figure 1-4).2.Cardiovascular disease, hypertension, diabetes, cancer, and related disordersaccount for two-thirds of all deaths in North America(seeFigure 1-4).3.Combination of pooreating patternsandalack of physical activitymay bethesecond leading cause of death in the United States.4.Obesity is second leading cause of preventable death in North America.1.3What Are the Classes and Sources of Nutrients?A.Overview1.The six classesof nutrientscan becategorized by function(see Table 1-1).a.Provide calories to meet energy needsb.Promote growth, development, and maintenancec.Regulate bodyprocesses2.The six classes of nutrients are also categorized by daily needs.a.Macronutrientsare needed in gram or cupquantitieseach day.b.Micronutrientsare needed in milligram or microgram quantities eachday.B.Carbohydrates

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1.Simple sugars(monosaccharides and disaccharides)2.Complex carbohydrates (polysaccharides)a.Starch (digestible)b.Fiber (indigestible)3.Primary source of energy (4kcal/g)C.Lipids (i.e., fats, oils)1.Energy yield: 9kcal/g2.Primary form of energy storage3.Animal fats (butter and lard) aresolid at room temperature4.Plant oils are liquid at room temperature5.Essential fatty acidsa.Not produced bythebody andmust be consumed(essential nutrient)b.Roles in blood pressure regulation and synthesis/repair of cellsc.Small amount requiredi.Fourtablespoonsoil per dayii.Serving of fatty fishat least twice a week.D.Proteins1.Functionsa.Structural components of muscle and boneb.Blood componentsc.Body cell structured.Enzymese.Immune factors2.Energy yield: 4kcal/g(limited use forenergy)3.Building blocks of proteins areamino acids4.Dietary sourcesa.Animalb.Plant5.Typical North Americanconsumesup totwotimes daily requirement.E.Vitamins1.Enable chemical reactions2.Provide no energy (0 kcal/g)3.13vitamins categorized by solubilitya.Fat-soluble (vitamins A, D, E, and K)i.Main sources: dairy products, nuts, seeds, oils, breakfast cerealsii.Not readily excretedfrom the bodyiii.Some mayaccumulate in the body towardtoxiclevels (i.e.,vitamin A)b.Water-soluble (B vitamins and vitamin C)i.Mainsources: fruits and vegetablesii.Easily destroyed by cookingiii.Most are readily excretedfrom the bodyF.Minerals1.Inorganic—do not contain carbon2.Not destroyed by cooking, but canbe lost in cooking water3.Provide no energy (0 kcal/g)

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4.Functions: role in nervous system, water balance, structural systems, and othercellular systems5.Sixteenor more essential minerals6.Categorized bydietary needa.Major minerals (needed in amounts greater than 100mg)b.Trace minerals (needed in amounts less than 100mg)7.Electrolytes—minerals that function based on electrical chargewhendissolved in water(sodium, potassium, and chloride)G.Water1.Functionsa.Solventb.Lubricantc.Transport of nutrients and wastesd.Medium fortemperature regulation andchemical processes2.Human body isapproximately60% water3.Human needsa.Men: 13 cups/dayb.Women: 9 cups/day4.Sourcesa.Beveragesb.Foodsc.By-product of metabolismH.Other important components in food1.Phytochemicalsa.Found in foods from plantsources, and especially infruits andvegetablesb.Not essential nutrientsc.Provideavariety of health benefitsand may reduce risks for certaindiseasesd.Foods with high phytochemical content are referred to as“superfoods.”e.Table 1-2lists common foodsourcesof some phytochemicals.2.Sphingolipids and conjugated linoleic acid (CLA)a.Found in meat and dairy productsb.Show some health benefitsI.Sources of nutrients1.500g(1 pound) protein, fat,and carbohydrates consumed daily2.20gminerals (in total)consumed daily3.300mgvitamins (in total)consumed daily4.Genetic material directs the use of nutrients in the body.1.4What Math Concepts Will AidYour Study of Nutrition?A.Calories1.Sourcesa.Carbohydrates (4kcal/g)b.Lipids (9kcal/g)

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c.Proteins (4kcal/g)d.Alcohol (7kcal/g; notan essentialnutrient, therefore not required)2.Most foods provide more thanonecaloriesource3.Energy (kcal) is used toa.Build new compoundsb.Perform muscular movementsc.Promote nerve transmissiond.Maintain electrolyte balance within cells4.Energyderived from foodis measured inkilocalories(kcal)a.1 calorie = heat energy needed to raise the temperature of 1 gram ofwater 1°Cb.1 kilocalorie (Calorie) = 1000 calories(1 kcal)= heat energy needed toraise the temperature of 1000gramsofwater 1°Cc.On food labels,“calories”without a capital“C”means kcal.d.Figure 1-5is a food label example of whole wheat bread.B.Calculating calories1.Use the4-9-4estimates to calculate calories from carbohydrate, fat, andprotein.2.Use the4-9-4estimates to determine what portion of total calorie intake iscontributed by carbohydrate, fat, and protein.C.Percentages1.Percent refers to a partof the total when the total represents 100 parts.2.Nutrition relevance: Used often when referring to menus and nutrientcompositionD.The metric system1.1 ounce = 28grams2.1 kilogram = 2.2 pounds3.1millimeteris approximately the thickness of a dime4.1 inch.= 2.54 centimeters5.1quart= 0.946 liters1.5How Do We Know What We Know About Nutrition?A.The scientific method (seeFigure1-6)1.Make observations and ask questions.2.Develop hypothesisa.Generated by observing natural phenomenonb.Generated by studying patterns among population groups3.Epidemiology is the study ofdietand disease patterns among variouspopulations.4.Controlled experiments are conducted totesthypotheses.a.Double-blind placebo controlled studydesignisthemost rigorous typeof experiment—neither researcher norparticipant is aware ofthegroupassignment.i.Experimental groupii.Control group

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b.Case–control study designinvolvescomparisons made betweenindividuals with and without certain conditions.B.Testing a hypothesis: can a high-fat diet cause weight loss? (see Figure 1-6)1.Observations made and questions asked2.Hypothesis generated3.Research experiments conducted4.Results evaluated by other scientists and published.5.Follow-up experiments conducted to confirm or extend the findings6.Accept or rejecthypothesis?C.Types of experiments (seeFigure1-7)1.Human studies provide strong evidence about relationshipsbetween nutrientsand health.2.Animalmodel3.Case–control studies4.Epidemiological studiesa.Studyeatingand disease patterns amongpopulations.b.Suggesthypothesis thatthen needsto be tested by controlledexperiments.1.6What Is the Current State ofNorth American Eating Patterns and Health?A.Does obesity threaten our future?1.Obesity is defined as having an excessive amount of bodyfat relative to leantissue.2.It is estimated thatmore than36.5%of adults are obese.3.Two-thirds of adults and1/3 of children are overweight or obese.4.Robert Wood Johnson Foundation report:F as in Fat: How Obesity ThreatensAmerica's Future2013(see Further Reading 12).a.Self-reported, state-by-state obesity data from the CDC(see Figure 1-8)b.Calls for national commitment to the prevention of obesity by 2030.5.Obesity plays a role in chronic illnesses.a.Heart diseaseb.Strokec.High blood pressured.High cholesterole.Diabetesf.Arthritisg.Certain cancers6.Problem: Consumption of too many energy dense, nutrient poor foods whileliving a sedentary lifestyleB.Assessing the current North Americaneating pattern1.National Health and Examination Survey (NHANES) datafrom 2009to2012indicates:a.16% of calories as proteins (FNBrecommends 10%to35%)b.50% of calories as carbohydrates (FNB recommends 45%to65%)c.33% of calories as fats (FNB recommends 20%to35%)

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2.Majority (2/3) of protein intake for most North Americans is from animalsources3.Approximately half of carbohydrates are from simple sugar sources, with theremaining coming from starches such as pastas, breads, and potatoes.4.Approximately 60% of dietary fats are from animal sources.5.NHANES 2011–2012 results show positive trends toward healthier lifestyles.a.Daily calorie consumption is decliningb.Soda (full-calorie) intake has declined 25% since late 1990s.6.Consume a variety of nutrient-dense foodswithin and across the food groups,especially whole grains, fruits, vegetables, low-fat or fat-free milk or milkproducts, and lean meats and other protein sources7.Balance calorie intake withenergyneeds.a.Increase intake of nutrient-densefruits and vegetablesb.Decrease intake of energy-dense foods such as sugary beverages andfattyfoodsC.Health objectives for the United States for the year 20201.Healthy People 2020isissued by the U.S. Department of Health and HumanServices’ (DHHS) Public Health Service.a.Health objectives for our nation released every 10 yearsb.Contains more than 600 health objectives across 42 topic areasc.Outlines national standards to:i.Eliminate health disparitiesii.Improve access to health education and careiii.Strengthens public health services and efforts2.Overarching goalsa.Attain high-quality, longer lives free of preventable disease, disability,injury, and premature death.b.Achieve health equity, eliminate disparities, and improve health of allgroups.c.Create social and physical environments that promotegoodhealthforall.d.Promote quality oflife, healthy development, and healthy behaviorsacross all life stages.3.Seewww.HealthyPeople.govfor more information4.Nutrition and Weight Statusa.Topic area specific to nutritionb.Includes targeting individual behaviorsc.Focuses on policies and environments that impact these behaviors incommunity settingsd.Maintaining a healthy weighte.Supporting the benefits ofa healthfuleatingpatterni.Consuming a variety of nutrient-dense foods within and acrossthe food groups, especially whole grains, vegetables, fruits, low-fat or fat-free milk or milk products, and lean meats and otherproteins.

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ii.Limiting intake of solid fats, cholesterol, added sugar, sodium(salt),and alcohol.iii.Limiting intake of calories to meetcaloric needs.f.Table 1-3presents a list of the six categories of objectives for HealthyPeople 2020 Nutrition and Weight Status with 22 specific objectives.g.Table 1-4presents a detailed sample of Nutrition and Weight StatusObjectives anddetails about the current status andtarget goals for2020.5.New topic areas included in Healthy People 2020a.Highlights and focuses on changes in health needs of certain life stagesi.Early and middle childhoodii.Adolescenceiii.Older adultsb.Genomicsi.Investigating the relationship of nutrition and geneticsii.Nineoutof10leading causes of death have a geneticcomponent.1.7What Can You Expect from Good Nutrition and a Healthy Lifestyle?A.Healthy weight1.Seekalifestyle to promote weight maintenance.2.Recognize thatweightgaincan be associated with overweight/obesity andrisks for chronic illnesses.3.Increased options for food as result of continual innovation by foodmanufacturers4.Incorporate physical activity into the daily routine as much as possibleB.Longer, healthier lives1.North Americans live longer and enjoy better health.2.Improve health by decreasingintake of animalfats and cholesterolandincreasingintake of fruits and vegetables.C.The total diet1.There are no “good” or “bad” foods.2.“The total diet or overall pattern of food eaten is the most important focus ofhealthy eating”(American Academy of Nutrition and Dietetics).3.Other ways to promote healthand prevent chronic diseasesa.Consume enough essential nutrients while moderating energy, solidfat, added sugar, andalcohol intake.b.Obtain regular physical activity (30–60minutesmost days).c.Minimize alcohol intake.d.Obtain adequate sleep (7–9 hours per night).e.Consume recommended amounts of water daily.f.Reduce stress.g.Use medications only when necessary.h.Abstain from illicit drug use.i.Maintain healthy relationships.

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1.8Nutrition and Your Health: Eating Well in CollegeA.Overview1.Habits of college students fall short of recommendations for whole grains,vegetables, fruits, milk, and meat; include too much fats,sweets, and alcohol.2.Health behaviors formed during young adulthood are likely to persistthroughout life.B.Food choices1.Stress may negatively impact nutrition and activity habits.2.Abundance of energy-dense, nutrient-poor food choices on collegecampuses3.Meals are a time for socialization.C.Weight control and the “Freshman Fifteen”1.A recent study (see Further Reading17) of7000 U.S. college students foundthat students gain 2.4–3.5 pounds during their first year away from home.a.Heavyalcoholconsumptionb.Working during college2.Maintaining healthy weight and losing excess weightwill improve short-termand long-term health.3.Losing excess weighta.Set several, small, achievablegoals.b.Monitor foods and activities(Use interactive tools onwww.ChooseMyPlate.gov).c.Gradual weight loss of 1–2 pounds per week (deficit of 500kcal/daybelow needs)d.Eat a balanced breakfast.e.Moderate use of alcohol and sugary beverages (including gourmetcoffee beverages)f.Exerciseregularlyi.Enjoyable activitiesii.Work out with a friendD.Alcohol and binge drinking1.Binge drinkinga.Five or more drinks in a row for menb.Four or more drinks in a row for women2.Moderatealcoholintakea.Two drinks a day or lessfor menb.One drink a day for women3.39% ofstudents on college campuses participatein binge drinking.4.Alcohol-related health risksa.Accidents/injuriesb.Unsafe sex and its consequencesc.Long-term health problemsd.Suicidese.Academic problemsf.Legal troublesg.Alcohol abuse or dependence5.20%of college students meet criteria for alcohol use disorders.

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E.Eating disorders1.30%of college students are at risk of developing an eating disorder.2.Short-term disordered eating patterns may progress to an eating disorder.3.Food becomes the focus of emotional issues.4.Risksa.Limited academic performanceb.Loss of menstrual periodsc.Thinning bonesd.Gastrointestinal problemse.Kidney problemsf.Heart abnormalitiesg.DeathF.Choosing a vegetarianlifestyle1.Plant-basedeating patternscan be a healthful lifestyle, but require appropriateplanning2.Fortified breakfast cereals providemany vitamins and minerals.3.Many vegetarian options available4.Tips to optimize nutritional benefit of plant-basedeating patterns.a.Choose baked,steamed, or stir-fried rather than deep-fried.b.Choose whole grains rather than refined carbohydrates.c.Consume foods fortified with vitamins and minerals.G.Fuel for competition: student athletes1.Increased calorie and nutrient needs.2.Avoid severe calorie restriction—carbohydrate and fat supply energy toexercising muscles.3.Emphasis on fluids—sports drinks are ideal for events lasting longer than 60minutes4.Losing fluid intentionallyis an unhealthy practice.5.Expensive supplements are not necessary.H.Tips for eating well on a college student’s budget1.Participate in a prepaid campus meal plan.2.Planning ahead will save money and improve nutrient intake.3.Never shop on an empty stomach.4.Buy store brands.5.Make use of canned and frozen fruits and vegetables and dry foods.6.Purchase concentrated fruit juicesand mix at home.7.Eggs and peanut butter are inexpensive sources of protein.RATE YOUR PLATEI.Examine Your Eating Habits More CloselyChoose a day of the week that is typical of your eating pattern.Using the first table foundin Appendix C, list all foods and drinksyou consumed for 24 hours. In addition, writedown the approximate amounts of food you atein units, such as cups, ounces, teaspoons,and tablespoons. Place the corresponding abbreviation from the list below in theReason

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Choicecolumn to indicate why you picked that food or drink. There can be more thanone reason for choosing a particular food or drink.FLVRFlavor/textureADVAdvertisementPEERPeersCONVConvenienceWTCLWeightcontrolNUTRNutritive valueEMOEmotionsHUNGHunger$CostAVAAvailabilityFAMFamily/culturalHLTHHealthApplicationAsk yourself what your most frequent reason is for eating and drinking. To what degreeishealth or nutritive value reason for your food choices? Should you make these higherpriorities?I choose many foods because they are considered healthy and will help with my healthgoals and weight maintenance. Other times I am choosing foods that I am used to eatingor because I am craving something sweet (taste). I should start to think of the nutrientsprovided by different foods, and some new foods I have not tried, in order toadd somevariety to myeating pattern. This variety will help me meet more of my nutrientrequirements. I could add variety at breakfast, for example, with fruit. I could addahealthy snack in the afternoon, such as low fat yogurt and granola,rather than drinkingregular cola. I noticed that this a time I am often hungry. This will also help me meetmore of my nutrient requirements, such as calcium, and fiber.

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II.Observe the Supermarket ExplosionToday’s supermarkets carry up to 60,000 items. Think about your last grocery shoppingtrip and the items you purchased to eat. Following is a list of 20 newer food productsadded to supermarket shelves. For those items you have tried, use the key from Part I toidentify why you chose those products.Answer choices may vary. Below are examples of why one might choose thefollowingfood products.CONVPrepackaged salad greens (variety packs other than iceberg lettuce)HLTHGourmet or sprayable salad oils (e.g.,walnut, almond, olive,or sesame oil)CONVPrecooked frozen turkey patties, precooked baconPEER/CONVMicrowavable sandwiches (e.g.,Hot Pockets or frozen sandwiches)CONVMicrowavable meals in a bowl (e.g.,mac and cheese, or soup)CONVRefrigerated precooked pasta (e.g.,tortellini orfettuccini) and accompanyingsauces (e.g.,pesto or tomato basil)HLTHImported grain products (e.g.,risotto,farfalle, gnocchi, or fusilli)$____Whole-grain pasta or rice

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CONVFrozen dinners (list your favorite of any of the wide variety)WTCLBottle water (flavored or unflavored)ADVTrendy juices(e.g.,draft apple cider, acai, or pomegranate)ADV/FLVR/CONVRoasted and/or flavored coffees (e.g., beans, ground, instant, or K-Cups)CONVInstant hot cereal in a bowl (add water and go!)CONV“Fast-shake” pancake mix (add water, shake, and ready to cook)FLVR/HUNGBreakfast bars or cookies (e.g., granola or fruit-flavored bars)HLTHDried fruit and nut mixesHLTHMeal replacement/fitness products (e.g., “energy” bars, high-protein bars, orsports drinks)HLTH/ADVLow-calorie muffin tops or bagel thinsCONV/HLTHPackaged yogurt smoothiesHLTH/ADVMilk substitutes (e.g., rice milk or soy milk)Finally, identify three new food products not on this list that you have seen in the pastyear. Discuss the appeal of these products to the North American consumer.Some other new food product examples include,but are not limited to:•Ready to eat, microwavable side items (e.g., mashed potatoes, macaroni andcheese, green beans casserole) appeal to individuals and families that valueconvenience.•Vitamin enhanced water offersa health advantage to plain water, for individualswho may not be meeting nutrient needs.•“Take and bake” breads appeal to individuals and familiesthat desirehot bakedbread with a meal but lack the time to prepareand bakeit fresh. There are avariety of brands including organic, multigrain, sourdough, Italian, etc.•Prepackaged, washed,and cut fruit and/or vegetables allow individuals to eatfresh produce without spending time towash, and/or cut.

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CHAPTER 2DESIGNING A HEALTHYEATINGPATTERNOVERVIEWThis chapter exploresthecomponents of healthyeatingpatterns, namelythose that willminimizetherisks of developing nutrition-related diseases.Threeprinciplesof a healthfuleatingpattern(variety, proportionality,moderation)as well as nutrient and energy density are discussed.The purpose and key recommendations of the Dietary GuidelinesandPhysical Activity Guidelinesfor Americans are explained.Tools for planning and evaluating dietary intake are discussed,includingthe Dietary Reference Intakes (DRI),theDietary Guidelines,ChooseMyPlate.gov,theMediterranean Diet,nutrient standards, and food labels.An overview of nutritional status and itsassessment is provided.Suggestionsare outlined to highlight thebest approach to evaluatenutrition information.KEY TERMSAdequate intake(AI)Anthropometric assessmentBiochemical assessmentClinical assessmentDietary assessmentDietaryReference Intakes (DRIs)Environmental assessmentEnergy densityEstimatedEnergyRequirement(EER)Functional foodsHeart attackMalnutritionMegadoseNutrient densityNutritional stateOvernutritionPhytochemicalRecommended DietaryAllowance(RDA)SubclinicalSymptomUndernutritionTolerable Upper IntakeLevel(UL)STUDENT LEARNING OUTCOMESChapter 2 is designed to allow you to:2.1Usevariety, proportionality, and moderation, as well as nutrient and energy density, todevelop a healthyeating plan.2.2List the purpose and key recommendations oftheDietary Guidelinesand thePhysicalActivity Guidelines for Americans.2.3Design a meal that conforms to the MyPlate recommendations as well astotheMediterranean diet and/or other diet planningguides.2.4Describe the three states of nutritional health.2.5Outline the measurements used (ABCDEs) in nutritional assessment:Anthropometric,Biochemical,Clinical,Dietary, andEnvironmental status.2.6Describe the specific nutrientrecommendationcategories within theDietary ReferenceIntakes.2.7Identify reliable sources of nutrition information.

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2.8Describe the components of the Nutrition Facts panel and the various health claims andlabel descriptors that are allowed.LECTURE OUTLINE2.1A Food PhilosophyThat WorksA.Overview1.Consume a variety of foods balanced by a moderate intake of each food.2.Principles of variety, moderation, and proportionalityB.Variety means eating many different foods1.Choosefoods from all the foodgroups and subgroups.2.Use MyPlate as a guide.a.Vegetablesb.Fruitc.Grainsd.Proteine.Dairy3.No single food meets all nutrient needs.4.Various phytochemicals are present in fruits and vegetables.a.Provide health benefits beyond nutrient needs.b.Some phytochemicals canreducetherisk of disease.c.Table2-1provides tips for boosting the phytochemical content of theeating pattern.5.Functional foodsprovide health benefits beyond those supplied by thetraditional nutrientsthatthe food contains.C.Proportionality means eating more nutrient-dense foods1.Proportionalityis also referred to as balance.a.Increased intake ofnutrient-dense foods (fruits, vegetables, wholegrains, low-fat dairy products).b.Decreased intake offoods that are high in certain fats, sugars,cholesterol, salt, and alcohol.c.Matchcalorie intake with energy expenditure to achieve or maintain ahealthy weight.2.Nutrient density is theratio of the amount of one or more nutrients (e.g.,protein, vitamins,andminerals) in a foodrelative tothe calorie content of thefood.a.Figure 2-1 illustrateshow tochoose more nutrient dense foods.b.Menuplanning should focus on the total diet: overall, choose morenutrient-dense foods and fewer empty-calorie foods.c.Nutrient density isparticularly important for those who consume fewcalories (e.g., on a weight-loss diet, children, older adults).D.Moderation refers mostly to portion size1.Don’t overconsume a specific nutrient.2.Moderate intake of fat,sugars,salt,alcohol,and calories.3.Energy density:compare the calorie content with the weight of the food.a.Highenergy densityfoods include nuts, fried food, cookies.

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b.Low energy densityfoods contain high amounts of water and fiber (e.g.,fruits and vegetables)andpromote satiety without high calorie content.c.People tend to consumefewer calories when eating low energy densefoods.d.Table 2-2 presents the energy density of common foods.e.Foods can be nutrient dense and energy dense at the same time.2.2Dietary andPhysical Activity GuidelinesA.Dietary Guidelines—the basis for meal planning1.Designed to inform the development of food, nutrition, and health policies andprograms.2.Five foundational guidelines of the 2015–2020 Dietary Guidelinesa.Follow a healthyeating pattern across the lifespan.b.Focus on variety, nutrient density, and amount.c.Limit calories from added sugars and saturated fats and reduce sodiumintake.d.Shift to healthier food and beverage choices.e.Support healthy eating patterns for all.3.Figure 2-2showsKey Recommendationsthat accompany the DietaryGuidelines andfurther detailshealthy eating patterns.4.Healthy eating patterns are the hallmark of the 2015–2020 Dietary Guidelines.a.Goal: support healthy weight and reducetherisk of chronic disease.b.Follow Healthy U.S.-Style Eating Pattern (see Table 2-5).c.American eating patternsarelow in vegetables, fruits,totalgrains,dairy,protein foods, and oil; intake isadded sugars, saturated fats, andsodium(see Figure 2-3).5.Meeting nutrient needs within calorie limits could alleviate many chronicdiseases.6.Figure 2-4showsestimateddailycalorie (kcal) needsbased on age and activitylevel.7.Nutritional needs should be metprimarily from foods.8.Increase intake of vegetables, fruits, whole grains, fat-free or low-fat dairy,seafood, lean meats and poultry, eggs, beans and peas, nuts and seeds, and oils.a.Contribute to nutrient adequacyb.Lower intake of problem nutrientsc.Improve gastrointestinal functiond.Aid in weight managemente.Decreasetherisk of chronic diseases9.Limit intake of added sugars(less than 10% total kcal/day), saturatedfat(lessthan 10% kcal/day),transfats, and sodium(less than 2300mg/day).10.Table 2-3 providestheexamples of recommended changesto the eating patternbased on Dietary Guidelines.B.Physical Activity Guidelines for Americans(see Table 2-4)1.Regular physical activity produces long-term health benefits2.Guidelines for children(6+)and adolescentsa.≥ 60 minutes of physical activity per day

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b.Include aerobicandmuscle-strengthening and bone-strengtheningexercises.c.Activitiesthat areappropriate for age, enjoyable, and offer variety.3.Guidelines for adultsa.Avoid inactivity.b.≥150 minutes per week of moderate-intensity or≥75 minutes per weekof vigorous-intensity physical activity.c.Include muscle-strengthening activities 2 or more days per week.4.Guidelines forsafe physical activitya.Understand the risks and chooseappropriate activities for fitness leveland health goals.b.Use appropriate gear and exercise in safe environmentsc.Consult with health care provider if there are chronic conditions andsymptoms2.3MyPlate—A Menu-Planning ToolA.Overview1.MyPlate wasreleased in 2011 and is a visualdepiction of healthyeating forAmericans.2.MyPlateshapes Dietary Guideline recommendations into a visual place setting(see Figure 2-5).B.Dishing up MyPlate1.MyPlate providesavisual representation ofahealthy plate at mealtimes.2.The MyPlate icon emphasizes five food groups.a.Fruits and vegetablescover half of the plate.b.Grains cover slightly more than one-fourth of the plate; half of yourgrain intake should be from whole grain products.c.Proteincovers the remaining portion of the plate;emphasizevariety ofprotein foods including seafood, lean meats and poultry, eggs, legumes,(beans and peas), nuts, seeds, and soy products.d.Dairy appears as a cup next to the plate;consume2 to3 cups of fat-freeor low-fat dairy products or otherrichsources of calcium.e.There is noseparate group for fats or oils; limit solid fats and emphasizeoils.C.Build a healthy eating style1.All food and beverage choices matter—focus on variety, amount, andnutrition2.Choose an eating style low in saturated fat, sodium, and added sugars3.Make small changes to create a healthier eating stylea.Each change is a personal “win,” and each MyWin is a change to build ahealthy eating style.b.Start with a few small changes4.Support healthy eating for everyoneD.MyPlate daily checklist1.ChooseMyPlate.gov features an interactive tool,MyPlate Daily Checklist,forindividuals to estimate their calorieneedsandsuggests afood pattern based onage, gender, height, and weight.

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2.Table 2-5 presents theHealthyU.S.-Style Eating Pattern: recommendedamounts of food from each MyPlate food group at 12 kcal levels.3.Helpful visual aids for estimating servings sizesare illustratedin Figure 2-6.4.MyPlate setsthelimits for empty calories;MyPlate Daily checklistsallow forsome empty caloriesthroughout the day (usually 120-160 kcal per day).E.Additional MyPlate resources1.USDA’s Ten Tips Nutrition Education series2.What’s Cooking? USDA Mixing bowl–help with meal planning, cooking, andgrocery shopping3.Food-A-Pedia4.SuperTrackerF.Menu planning with MyPlate (see Table 2-7)1.MyPlate guidelines are not intended for infants or children under2 years of age.2.Variety is key, as each food will provide different nutrients and each food groupis important (see Table 2-6).3.There can be variation in the amount of nutrients and calorie content of foodswithin each food group.4.Choosing fat-free or low-fatdairyoptions allows for greater amounts offoodsfrom other groups in your daily plan.5.Plant foods can be good sources of protein.6.Focus on colorful fruits and vegetables to increase the nutritional quality ofthese choices.7.Choose whole grain products instead of refined grains.8.Include healthy oils from plants and fish as part of your weeklydietary pattern.G.Limitations of MyPlate1.The MyPlate icon does not provide information about overall calories, servingsizes, or number of servings.2.The MyPlate icon does notaddresstypes offood choices to make within eachfood group.3.The MyPlate icon does notaddresstotal diet, which includes foods eatenbetween meals.4.Public health campaign may not reach all of its intended audience.H.How does your plate rate?1.Use SuperTracker tool to compare your overall intake to your personalizeddaily food plan.2.Use NutritionCalc software to compare your intakes to the DRIs.I.TheMediterraneanDiet Pyramid (see Figure 2-8)1.Useful alternative to MyPlate2.The 2015–2020 DietaryGuidelines includes the Healthy Mediterranean-StyleEating Pattern.3.Dietary pattern is linked to low rates of chronic disease and increased lifeexpectancy.4.Emphasizes minimallyprocessed, plant-based foods at each meal5.Emphasizes healthy fats (e.g.,olive oil,avocado, nuts)and limits saturated fats6.Fish and seafood consumed2x/week7.Encourages 5–10 servings offruits and vegetables each day

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8.Choose plant proteins more often and moderate intake of lean proteins and low-fat dairy products.9.Red meats and sweet desserts are consumed less often10.Includes regular physical activity11.Incorporates moderate wine consumption12.Water is the beverage of choice.2.4States of Nutritional Health(see Figure 2-9)A.Desirable nutrition1.Body tissues have enough of anutrient to support normal metabolic function.2.Surplus of nutrientscan be used in times of need.B.Undernutrition1.Form of malnutrition in which nutrient intake does not meet nutrient needs.2.When nutrient levels fall sufficiently low,health declines andbiochemicalevidence appears.3.Subclinicaldeficiency shows nooutward signsto reflect low nutrient levels andslow metabolic processes.4.Clinical deficiency develops within months or years of the undernutrition;clinicalsymptoms often evident in skin, hair, tongue, or eyes.C.Overnutrition1.Form of malnutrition characterized by prolonged consumption of more nutrientsthan the body needs2.Example: too much vitamin A can have negative effects during pregnancy3.Excess calorie intake is most common indevelopednations.4.The difference betweendesirable and overnutritionisusuallylarge, but isthesmallest for vitamin A, calcium, iron, and copper.2.5Measuring Your Nutritional StateA.Analyzing background factors1.Familyhealthhistory2.Medical history3.Medication list4.Social history5.Educationlevel6.Economic statusB.Assessing nutritional status using the ABCDEs(see Table 2-8 and Figure 2-10)1.Anthropometric assessment: height, weight, body composition, circumferences.2.Biochemical assessment: measuring nutrients or by-products in the blood andother body fluids.3.Clinical assessment: looking for physical evidence (e.g., high blood pressure).4.Dietary assessment: examining dietary intake.5.Environmental assessment(from background analysis).C.Recognizing the limitations of nutritional assessment1.Clinical symptoms of nutrient status may take years to develop.2.Manyclinical symptomsare not specific toonlya nutrient deficiency.D.Concern about the state of your nutritional health is important

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1.Maintaining nutritional health can lead toalong and vigorous life.2.Maintaining nutritional health can reduce disease risk.2.6Specific Nutrient Standards and RecommendationsA.Overview1.Dietary Reference Intakes(DRI) is the umbrella term that describes fourstandards for nutrient needs.2.Table 2-9 explains the usage of the DRI’s and Daily Value.B.Recommended Dietary Allowances (RDA)1.Amount of a nutrient that meets the needs of~97% of all healthy individualsin a particular age and gender group2.Intakesslightly above or below the RDA are of no concern3.Intakes below70%RDA or 3x or more above the RDAfor an extended periodcan lead to deficiency or toxicity, respectively.C.Adequate Intake (AI)1.Set if there is not sufficient information on human needs toset an RDA2.Further research is required before scientists can establish a more definitivenumber3.Derived from dietary intakes of people who appear to be maintainingnutritional health (no deficiency apparent)D.Estimated Energy Requirement (EER)1.Not set higher than average need (as for vitamins and minerals) because thiswould lead to excess calories and weight gain; starting point for estimatingcalorie needs.2.Takes into account age, gender, height, weight, and physical activity.3.Also accounts for additional needs during growth and lactation.E.Tolerable Upper IntakeLevel (UL)1.The highest amount of a nutrient that is unlikely to cause adverse healtheffects in the long run for most people.2.Usually seen witheating patternspromoting excess intake of alimited varietyof foods, many fortified foods, or megadoses of specific vitamins or minerals.F.Daily Value(not part of DRIs)1.Generic standard used on food labels—usually reflects the highest RDA (orrelated nutrient standard) seen in various age and gender categories for thenutrient.2.Based on a 2000-kcal diet.3.Allows consumers to compare intake from a specific food to desirable (ormaximum) intake levels.G.How should these nutrient standards be used?1.The type of standard that is set depends on the quality of available evidence.2.Eating patternsshould strive to meet the RDA or AI without exceeding theUL.3.AI should not be used alone to evaluate individual needs.4.EER isanestimate and may need to be adjusted.

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5.Standards for each nutrient arefound in appendix G of the text or at the linkfor Dietary Guidance at the Food and NutritionInformationCenter’s website(https://fnic.nal.usda.gov/dietary-guidance/dietary-reference-intakes)6.Daily Values, which appear on food labels, serve as rough guidelines forcomparison of nutrient content of foods to approximate human needs; set at orclose to highest RDA value.7.Figure 2-11illustrates how the various nutrient standards relate to each otherandtherisk for deficiency or toxicity.2.7Evaluating Nutrition InformationA.Ensure that the nutrition claim adheres to basic principles of nutrition (e.g.,DietaryGuidelines for Americans)B.Examine background and scientific credentials of the individual, organization, orpublicationmaking the nutritional claim.C.Beware of bad science1.Possible disadvantages are ignored2.Claims sound too good to be true; claim a “cure”3.Evidence of bias against medical community4.Touted as a “breakthrough”D.Consider the study1.Note the size and duration of the study; larger study and longer duration arebetter.2.Note the type of study (i.e., epidemiology, case–control, double-blind).E.Beware of hypeF.Expect a nutrition professional to1.Inquire about medical history, lifestyle, and currenteatinghabits2.Formulate an individualizedeating pattern3.Schedule follow-up visits to monitor progress4.Involve social support5.Consult with otherhealth professionalsG.Avoid megadoses ofnutrient supplements.H.Examine product labelscarefully.I.Seek advice from reputable professional, including a primary care physician orregistered dietitian nutritionist (RDN).2.8Nutrition and Your Health:Food Labels and Diet PlanningA.Overview1.Labels must include product name, manufacturer name and address, amount ofproduct in package, ingredients in descending order by weight.2.Monitored by FDA3.Nutrition Facts panel(Figure 2-12)must includea.Total calories(kcal)b.Total fatc.Saturated fatd.Transfate.Cholesterol

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f.Sodiumg.Total carbohydrateh.Fiberi.Total sugarsj.Added sugarsk.Proteinl.Vitamin A, vitamin D, calcium,iron,and potassiumm.Monounsaturated or polyunsaturatedfats, potassium,and others listedifhealth claims are made about themor if food is fortified with them.4.Percentageof the Daily Valueusually listedfor each nutrientper serving5.Serving sizes must be consistent among similar foods but are notnecessarilythesame as what is recommended by MyPlate’s Daily Food Plans.6.Nutrientclaims must follow legal definitions(see Table 2-10).B.Changes to nutrition labels approved1.Figure 2-13illustratesthe new Nutrition Facts Labels with changes noted thatwere approved May 2016.2.Increased type size for “Calories,”“Servings per container,” and the “Servingsize” declaration.3.The number of calories and “Serving size” declaration will beinbold.4.Daily value information for nutrients will be updated and will include the actualamount for vitamin D, calcium, iron, and potassium.5.“Added Sugars” is an addition to the label.6.“Calories from fat” will be removed.7.Serving size information will more accurately reflect how much is consumed inone sitting.8.Larger packages will have two columns on label to note “per serving” and “perpackage.”9.July 2018 isthedeadline forimplementation for manufacturers with $10million in food sales per year.C.Menuplanning with labels1.Daily Values generally align with RDAs and AIs for nutrients.2.Food labels are useful for identifying nutrient-dense foods.D.Exceptions to food labeling1.Fresh foods (e.g., fruit, vegetables,andfish) are not required to have NutritionFacts labels.2.Asprotein deficiency is so rare in the US, %DV for protein is not required fortheproducts designed for peopleaged4 years or older3.If % DV is included, theproduct must be analyzed for protein quality4.Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA)requires manufacturers to label food products that contain an ingredient that isor contains protein from a major food allergen.E.Health claims on food labels1.Fourcategoriesofclaimsare usedon food labelsa.Health claims–closely regulated by FDAb.Preliminary health claims–regulated by FDA but evidence may bescant for the claim

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c.Nutrient claims–closely regulated by FDA (see Table 2-10)d.Structure/function claims(notFDA approved, or necessarily valid)2.FDA permits some health claims with restrictionsa.There must beasignificant scientific agreement that a relationshipexists between thenutrient and the disease.b.Food must be a “good source” of fiber, protein, vitamin A, vitamin C,calcium, or iron.c.Single serving of the food product cannot contain more than 13 gramsof fat, 4 grams of saturated fat, 60 milligrams of cholesterol, or 480milligrams of sodium3.Current allowedhealthclaimsa.Calcium and vitamin D for reduced risk of osteoporosisb.Low total fat intakeand reduced riskof some cancersc.Low saturated fat and cholesterolintakeforreduced riskof cardio-vascular disease (CVD)d.Fiber from fruits, vegetables, and grainsforreduced risk of cancerse.Low sodium and high potassiumfor reduced risk of hypertension andstrokef.Fruits and vegetablesand reduced risk of some cancersg.Folate forreduced riskof neural tube defectsh.Sugarless gumfor reduced riskof tooth decayi.Fruits, vegetables, and grain products that contain fiber forreduced riskof CVD; oats and psyllium can be singled out in reduction of CVD riskj.Eating patternrich in whole grains and other plant foods, low in totalfat, saturatedfat and cholesterol for reduced risk of CVDk.Soy proteinand reduced risk of CVDl.Fatty acids from fish forreduced risk of CVDm.Plant stanols and sterolsfor reduced risk of CVD4.Table 2-10describes allowablenutrientclaims in detail, such asa.Sugar free:<0.5 grams per servingb.Reduced fat: 25% less fat than the reference productc.Fortified or enriched: vitamins or minerals have been added back to atleast 10% of what is normally presentd.Good source: serving offood contains 10–19% of the DV for aparticular nutrientRATE YOUR PLATEDoes Your Diet Compare to MyPlate?Using your food-intake record from Chapter 1, place each food item in the appropriate groupofthe accompanying MyPlate chart. That is, for each food item, indicate how many servings itcontributes to each group based on the amount you ate (see Food Composition Table Supplementfor serving sizes). Many of your food choices may contribute to more than one group. Forexample, spaghetti with meat sauce contributes to three categories: grains, vegetables, andproteins. After entering all the values, add the number of servingsconsumed in each group.

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Finally, compare your total in each food group with the recommended number of servings shownin Table 2-5 or obtained from the ChooseMyPlate.gov website. Enter a minus sign(–)if yourtotal falls below the recommendation or a plus sign (+) if it equals or exceeds therecommendation.Indicate the number of servings from MyPlate that each food yields:Food orbeverageAmountEatenGrainsVegetablesFruitsDairyProteinOrange juice1 cup00100Crispix1 cup10000Nonfat milk½ cup0000.50Sugar2 tsp00000Black coffee1 cup00000Diet cola12 oz00000Chicken sandwich withlettuce and mayonnaise3 oz chicken,2 slices whitebread,2 tspmayonnaise020000000000300Pear1 medium00100Nonfat milk1 cup00010Regular cola12 oz00000Pork chop3 oz00003Baked potato1medium01000Margarine2 tbsp00000Lettuce and tomato salad1 cup00.75000Ranch dressing2 tbsp00000Peas(green)½ cup00.5000Whole milk1 cup00010Cherry pie1 piece1.50000Iced tea12 oz00000Apple1medium001.500Water1 cup00000Group totals4.52.253.52.56Recommended servings(2000-kcal plan)62.5235.5Shortages/overages innumbers of servings--+-+

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CHAPTER 3THE HUMAN BODY: A NUTRITION PERSPECTIVEOVERVIEWThis chapter examines the anatomy and physiology of the human body as it pertains tonutrition. Comprehensive descriptions of the structure and functions of cells and organ systemsare described, including the circulatory system,urinary system,nervous system, endocrinesystem,immune system, and digestive system. A briefsectiondescribes the storage capabilitiesof the body.An introduction to digestion and absorption is presented as part of the discussion ofthe digestive system.The science of nutritionalgenomicsand its emerging application inpersonalized nutrition is introduced. TheNutrition and Your Healthsection reviews commonproblems with digestion, including heartburn,ulcers, constipation, hemorrhoids, irritable bowelsyndrome,diarrhea,gallstones, celiac disease, andnonceliacgluten sensitivity.KEY TERMSAbsorptive cellsAbsorptionActive absorptionAdenosine triphosphate (ATP)Adipose tissueAnal sphinctersAntibodyAntigenAnusAmylaseArteryAscending colonBileBileacidBolusCapillaryCardiovascular systemCatalaseCecumCeliac diseaseCell nucleusCholesterolChromosomeChymeConnective tissueConstipationCytoplasmDescending colonDeoxyribonucleic acid(DNA)DiarrheaDigestionDigestive systemDuodenumEndocrine glandEndocrine systemEndoplasmic reticulum(ER)Enterohepatic circulationEnzymeElectrolyteEpiglottisEpinephrineEpigeneticsEpigenomeEpithelial tissueErythropoietinEsophagusFacilitated diffusionFecesFODMAPsGallbladderGastroesophageal refluxdisease (GERD)Gastrointestinal (GI) tractGeneGene expressionGlutenGolgi complexHemorrhoidHepatic portal circulationHepatic portal veinIleocecal sphincterIleumInsoluble fiberInsulinIntrinsic factorJejunumLactealLaxativeLipaseLower esophageal sphincterLumenLymphLymphatic systemLysosomeMicrovilliMitochondriaMotilityMuscle tissueMyelinNervous systemNervous tissueNeuron

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KEY TERMS(continued)NeurotransmitterNonceliac glutensensitivity(NCGS)Nonspecific immunityNorepinephrineNSAIDsNutrigeneticsNutrigenomicsNutritional genomicsOleogustusOrganOrgan systemOrganellesPassive diffusionPerforationPeristalsisPeroxisomepHPhagocytosisPharynxPhospholipidPinocytosisPlasmaPrebioticProbioticProton pump inhibitorPyloric sphincterReceptorRectumRibonucleic acid (RNA)RibosomesSecretory vesiclesSigmoid colonSoluble fiberSpecific immunitySynapseThyroid hormonesTissuesTracheaTranscriptionTranslationTransverse colonUlcerUmamiUreaUreterUrethraUrinary systemVeinVilli (singular, villus)White blood cellsSTUDENT LEARNING OUTCOMESChapter 3 is designed to allow you to:3.1Understand some basic roles ofnutrients in human physiology.3.2Identify the functions of the common cellular components.3.3Definetissue, organ, andorgan system.3.4Identify the roleofthe cardiovascular and lymphatic systemsin nutrition.3.5List basic characteristics of the nervous system and its role in nutrition.3.6List basiccharacteristics of the endocrine system, especially the pancreas, and its role innutrition.3.7List basic characteristics of the immune system and its role in nutrition.3.8Outline the overall processes of digestion and absorption in the mouth, stomach, smallintestine, and large intestine, as well as the roles played by the liver, gallbladder, andpancreas.3.9List basic characteristics of the urinary system and its role in nutrition.3.10Understand the importance of the body storage areas for nutrients.3.11Understand the emerging field of nutritional genomics.3.12Identify the major nutrient-related gastrointestinal health problems and approaches totreatment.LECTURE OUTLINE3.1Nutrition’s Role in Human PhysiologyA.The human body is composed of trillions of cells.B.Levels of organization: cells→tissues→organs→organ systems

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1.Each cell isa self-contained, living entity2.Cells of the same typejointo form tissues3.One or more tissues combine to form organsa.Organs are important in nutritional healthb.Nutritional state determines how the organ functions4.Several organs cooperate and form an organ systemC.Constant chemical reactions within living cells require:1.Energy2.Water3.Building supplies (i.e.,protein, minerals)4.Regulation (i.e.,vitamins)3.2The Cell: Structure, Function, and Metabolism(see Figure 3-1)A.Cell (plasma) membrane1.Holds cellular contents together2.Regulates direction and flow of substance into and out of the cell3.Cell-to-cell communication4.Composed oflipid bilayer (double membrane), which contains:a.Phospholipids—water-soluble heads and water-insoluble tailsb.Cholesterol—fatsoluble; provides stabilityc.Proteins—function as structural support, enzymes, channels, receptors,and gatesd.Carbohydrates—identify cells, cell-to-cell communication, andimmune defenseB.Cytoplasm1.Fluid materialand organelles within the cell2.Site of anaerobic metabolismC.Mitochondria1.“Power plants”—convertthe chemicalenergystored within carbohydrates,proteins, and fatsinto energy that cells can use2.Site of aerobic metabolism3.All cells except red blood cells contain mitochondriaD.Cell nucleus1.All cells except red blood cells contain at least one nucleus.2.Bound by its own double membrane3.Contains genetic materiala.DNA→genes→chromosomesb.Gene expression—DNA directs synthesis of proteinsi.RNA carries DNA’s message to the outside of the nucleus(transcription)ii.On ribosomes, RNA’s message is used to synthesize a protein(translation)E.Endoplasmic reticulum (ER)1.Continuous network of tubes on the outer membrane of the cell nucleus2.Rough ER contains ribosomes—sites of protein synthesis3.Functions of ER

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a.Protein synthesisb.Some lipid synthesisc.Detoxification of toxic substancesd.Calcium storageF.Golgicomplex1.Sacs within the cytoplasm2.Package proteins in secretory vesicles for secretion by the cellG.Lysosomes1.Sacs contain enzymes for digestion of foreign material2.Active in immune functionH.Peroxisomes1.Contain enzymes that detoxify harmful chemicals, including alcohol2.Detoxification results in formation of hydrogen peroxide3.Catalase prevents accumulation of hydrogen peroxide in cellsI.Cell metabolism1.Chemical processes involved in maintaining lifea.Release and use of energy(adenosine triphosphate)from foodsb.Synthesis of compoundsc.Preparation of waste products for excretion2.Anabolic reactions put molecules together and require energy.3.Catabolic reactions take molecules apart and release energy (e.g., metabolismof energy-yielding nutrients)3.3BodySystems (see Figure 3-2)A.Types of tissue1.Epithelialtissuea.Covers surfaces inside and outside the bodyb.Secretes substancesc.Absorbs nutrientsd.Excretes wastes2.Connectivetissuea.Found in tendons, cartilage, bone, skin, blood vessels, and elsewhereb.Supports and protects the bodyc.Stores fatd.Produces red blood cells3.Muscletissuea.Found in skeletal muscles and organsb.Designed for movement4.Nervoustissuea.Found in brain and spinal cordb.Designed for communicationB.Systems may work together (e.g., digestive system aids immune system by preventingpathogens from entering the body).3.4Cardiovascular System and Lymphatic SystemA.Cardiovascular system

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1.Blood flows through the heart and blood vessels from pumping of the heart.2.Blood is made of plasma, red blood cells,white blood cells, platelets, andother substances.3.Blood circulation through the body(see Figure 3-3)a.Blood travels from the right side of the heart to the lungs to pick upoxygen and release carbon dioxide,andthen travels back to the heart.b.Blood travels from the left side of the heart through the arteries andcapillaries to deliver oxygen and nutrients and pick up wastes from thebody’s cells,andthen returns to the heart through veins.i.Capillaries have web-like pores.ii.Capillaries are only onecell-width thick.4.Portal circulation in the gastrointestinal tracta.Water and nutrients may be used to nourish cells of the gastrointestinaltract, but most are taken up by capillaries in the small intestine andstomach.b.Capillaries merge into veins that empty into the portal vein.c.Portal vein leads to the liver.d.Liver processes absorbed nutrients before they enter generalcirculation.B.Lymphatic system1.Lymph flows through the lymphatic vessels and lymph tissues.2.Lymph consists of plasma and white blood cells.3.Lymph flows throughout body and eventually empties into major veins nearthe heart.4.Flow is driven by muscle contractions from normal body movement.5.Lymphatic circulation in the gastrointestinal tract(see Figure 3-4)a.Lymph vessels that serve the small intestine are called lacteals.b.Lymph vesselspick upmostproductsof fat digestion and fatabsorption.c.These products are too large to enter the bloodstream directly3.5UrinarySystem(see Figure 3-5)A.Two kidneys1.Remove wastes from the blood2.Helptomaintain acid/base balance of the blood3.Convert vitamin D toitsactive hormoneform4.Produceerythropoietin (hormone that stimulates red blood cell synthesis)5.Produce glucose from amino acids during fasting6.Filter excess water-soluble nutrients and mineralsB.Urinetravels from kidneys to bladder by ureters.C.Bladder empties through urethra3.6Nervous SystemA.Functions1.Exercises central control over most body functions

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