Nutrition Chapter 3 Lecture Notes

Chapter 3Chapter 3

LectureLectureOutlineOutline

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Body OrganizationBody Organization

Cells form Tissues Cells form Tissues Tissues form OrgansTissues form Organs Organs form Systems (e.g., Organs form Systems (e.g.,

digestive)digestive)

Cell ProcessesCell Processes

Constant turnover of substancesConstant turnover of substances Require energy, adenosine Require energy, adenosine

triphosphatetriphosphate Require nutrientsRequire nutrients

Cell MembraneCell Membrane

Double layers of lipid, Double layers of lipid, carbohydrate, and proteincarbohydrate, and protein

Controls passage of substancesControls passage of substances Distinct identification structuresDistinct identification structures

OrganellesOrganelles

CytoplasmCytoplasm

Mitochondria Mitochondria —— Power plantPower plant– Major site for energy productionMajor site for energy production

Endoplasmic reticulum Endoplasmic reticulum —— Communication Communication networknetwork– Rough endoplasmic reticulum - protein Rough endoplasmic reticulum - protein

synthesissynthesis– Smooth endoplasmic reticulum - fat synthesisSmooth endoplasmic reticulum - fat synthesis

OrganellesOrganelles

Golgi ComplexGolgi Complex– Packaging site for proteinPackaging site for protein

LysosomesLysosomes– Cell’s digestive systemCell’s digestive system

PeroxisomesPeroxisomes– Detoxify harmful chemicalsDetoxify harmful chemicals

NucleusNucleus

Double membraneDouble membrane Genetic material DNAGenetic material DNA Directs protein synthesis and cell Directs protein synthesis and cell

divisiondivision

Four Types of TissuesFour Types of Tissues EpithelialEpithelial

– Lines the outside surfaces and external Lines the outside surfaces and external passagespassages

ConnectiveConnective– Holds structures togetherHolds structures together

MuscleMuscle– Contracts to cause movementContracts to cause movement

NervousNervous– Transports nerve impulsesTransports nerve impulses

Exchange of NutrientsExchange of Nutrients

Cardiovascular and Lymphatic Cardiovascular and Lymphatic SystemsSystems

Heart and blood vesselsHeart and blood vessels Blood Blood Pulmonary circulationPulmonary circulation Systemic circuitSystemic circuit Lymphatic systemLymphatic system

Cardiovascular SystemCardiovascular System

Capillary and Lymph VesselsCapillary and Lymph Vessels

Portal CirculationPortal Circulation

Transports nutrientsTransports nutrients From the small intestineFrom the small intestine Delivers to the liverDelivers to the liver

Blood CirculationBlood Circulation

Lymphatic SystemLymphatic System Contains lymphContains lymph Immune cells Immune cells Passage for large particlesPassage for large particles Empties into veins leading to the heartEmpties into veins leading to the heart

Nervous SystemNervous System

Regulatory systemRegulatory system Central Nervous SystemCentral Nervous System

– Brain and the spinal cordBrain and the spinal cord Peripheral Nervous SystemPeripheral Nervous System

– Branches out to organsBranches out to organs Basic unit is NeuronBasic unit is Neuron

– Responds to electrical and chemical Responds to electrical and chemical signalssignals

TransmissionTransmission

Sending SignalsSending Signals

Change in sodium and potassium Change in sodium and potassium concentrationconcentration

NeurotransmitterNeurotransmitter– Secretion of dopamine, epinephrine, and Secretion of dopamine, epinephrine, and

norepinephrinenorepinephrine Dependent on nutrient supply Dependent on nutrient supply

Endocrine System Endocrine System

Secretes regulatory substances Secretes regulatory substances (hormones)(hormones)

Target cells with receptor proteinsTarget cells with receptor proteins Body’s messengerBody’s messenger InsulinInsulin Thyroid hormonesThyroid hormones

Immune SystemImmune System

The SkinThe Skin

Continuous barrierContinuous barrier Effects of nutritional deficiencies Effects of nutritional deficiencies LysozymeLysozyme

The Intestinal CellsThe Intestinal Cells

Barrier to invading microbesBarrier to invading microbes ImmunoglobulinsImmunoglobulins Muscosal membrane Muscosal membrane Effects of nutritional deficiencyEffects of nutritional deficiency

White Blood CellsWhite Blood Cells

Attack microorganismAttack microorganism PhagocytesPhagocytes Cell-mediated immunityCell-mediated immunity

– AntibodiesAntibodies– Antibody-antigen responseAntibody-antigen response– Template (memory) madeTemplate (memory) made

The Digestive SystemThe Digestive System

The MouthThe Mouth

MasticationMastication TasteTaste SalivaSaliva

– SolventSolvent– EnzymesEnzymes– MucusMucus

The EsophagusThe Esophagus

Long tubeLong tube EpiglottisEpiglottis PeristalsisPeristalsis Lower esophageal sphincterLower esophageal sphincter HeartburnHeartburn

The StomachThe Stomach

SphinctersSphincters SizeSize Gastric juicesGastric juices Holding “tank”Holding “tank” Formation of chymeFormation of chyme Prevention of autodigestionPrevention of autodigestion

Physiology of the Stomach Physiology of the Stomach

Stomach AcidStomach Acid

Destroys activity of proteinDestroys activity of protein Activates digestive enzymesActivates digestive enzymes Partially digests dietary proteinPartially digests dietary protein Assists in calcium absorptionAssists in calcium absorption Makes dietary minerals soluble for Makes dietary minerals soluble for

absorptionabsorption

PeristalsisPeristalsis

The Small IntestineThe Small Intestine

Approximately 10 feet longApproximately 10 feet long Folded wallsFolded walls VilliVilli Absorptive cellsAbsorptive cells Rapid cell turnoverRapid cell turnover

The Small IntestineThe Small Intestine

Nutrient AbsorptionNutrient Absorption

Passive absorptionPassive absorption Facilitated absorptionFacilitated absorption Active absorptionActive absorption Phagocytosis and pinocytosisPhagocytosis and pinocytosis

Nutrient AbsorptionNutrient Absorption

The Large IntestineThe Large Intestine

Indigestible food stuff Indigestible food stuff No villi or enzymes No villi or enzymes Mucus-producing cellsMucus-producing cells Absorption of water, some Absorption of water, some

minerals, vitaminsminerals, vitamins BacteriaBacteria EliminationElimination

RectumRectum

Stool Stool EliminationElimination Muscle contractionMuscle contraction Anal sphinctersAnal sphincters

Accessory OrgansAccessory Organs PancreasPancreas GallbladderGallbladder LiverLiver

The LiverThe Liver

BileBile Enterohepatic Enterohepatic

circulationcirculation

The PancreasThe Pancreas

Digestive enzymesDigestive enzymes HormonesHormones

– Glucagon and insulinGlucagon and insulin Pancreatic juicesPancreatic juices

– BicarbonateBicarbonate

The Urinary SystemThe Urinary System

KidneysKidneys UreterUreter BladderBladder UrethraUrethra Waste productsWaste products Blood acid-base Blood acid-base

balance (pH)balance (pH)

Storage CapabilitiesStorage Capabilities

Maintaining reservesMaintaining reserves Adipose tissueAdipose tissue GlucoseGlucose Amino acids Amino acids Vitamins and mineralsVitamins and minerals

– Calcium in bonesCalcium in bones

GeneticsGenetics NutrigenomicsNutrigenomics Nutritional Diseases with a genetic Nutritional Diseases with a genetic

linklink– Cardiovascular diseaseCardiovascular disease– HypertensionHypertension– ObesityObesity– DiabetesDiabetes– CancerCancer– OsteoporosisOsteoporosis

Common Problems with Common Problems with DigestionDigestion

UlcersUlcers HeartburnHeartburn ConstipationConstipation HemorrhoidsHemorrhoids Irritable Bowel SyndromeIrritable Bowel Syndrome DiarrheaDiarrhea GallstonesGallstones

UlcersUlcers

Can occur in esophagus, stomach Can occur in esophagus, stomach and small intestineand small intestine

CauseCause– H. PyloriH. Pylori

HeartburnHeartburn Gastroesophageal reflux disease (GERD)Gastroesophageal reflux disease (GERD)

ConstipationConstipation Difficult or infrequent evacuationDifficult or infrequent evacuation CausesCauses

– Ignoring normal urgesIgnoring normal urges– Muscle spasmsMuscle spasms– Certain medicationsCertain medications

TreatmentTreatment– Dietary fiberDietary fiber– FluidsFluids– Regular physical activityRegular physical activity

LaxativesLaxatives

Irritate the intestinal nerve Irritate the intestinal nerve Draw water into the intestineDraw water into the intestine Regular use is harmfulRegular use is harmful

Hemorrhoids (piles)Hemorrhoids (piles)

Swollen veins of the rectum and anus Swollen veins of the rectum and anus Intense pressure and straining Intense pressure and straining Dietary recommendation:Dietary recommendation:

– Fiber and fluidFiber and fluid

Irritable Bowel SyndromeIrritable Bowel Syndrome SymptomsSymptoms

– Cramps, bloating, increased frequency, Cramps, bloating, increased frequency, diarrhea, constipationdiarrhea, constipation

CausesCauses– Altered intestinal peristalsisAltered intestinal peristalsis– Decreased pain thresholdDecreased pain threshold

Individualized treatmentIndividualized treatment– Elimination dietElimination diet– Moderate caffeineModerate caffeine– Low-fat, small, frequent mealsLow-fat, small, frequent meals– Stress reductionStress reduction

DiarrheaDiarrhea

Fluidity and frequencyFluidity and frequency CausesCauses

– InfectionsInfections– Poorly absorbed substancesPoorly absorbed substances

Treatment:Treatment:– Plenty of fluidPlenty of fluid

GallstonesGallstones

SymptomsSymptoms– Upper right abdominal pain, gas, Upper right abdominal pain, gas,

bloating, nausea and vomitingbloating, nausea and vomiting TreatmentTreatment

– Removal of gallbladderRemoval of gallbladder