digestion & nutrition · chemical digestion macromolecules broken down by enzymes define...

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DIGESTION & NUTRITION

MechanicalMouth-tongue with taste budsteeth -20 to 32palate-hard, soft

Epiglottis-swallowEsophagus-peristalsissphincters

Stomach-3 layers muscleSmall intestine-villi&microv.Large intestine- defecation

ChemicalSalivary glands(3 pr)amylase (starch)

Goblet cells –mucousGastric glands—HCl

& pepsin ( proteins)Bile-emulsifies fatsNAHCO3—more basicPancreatic enzymes-all 3Intestinal enzymes- all 3Bacteria-break & build (K)

Main Parts—Digestive System

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Fig. 12.3

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Order & Terms

LipsMouth-tongue, teethPharynx (By epiglottis)Esophagus (cardiac S.)Stomach (pyloric S.)

Duodenum//pancreasSmall Intestine

Colon (large intestine)Rectum to Anus

(Diarrhea & Constipation)

EnzymesTonsils—tonsillitisDental caries-bacteriaBoluspH scaleUlcer-Helicobacter pylori18’—4.5’Surface area-ABSORP.Lactealhormone

Fig. 12.4

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Fig. 12.5

Fig. 12.6

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Fig. 12.8

ACCESSORY Organs

Pancreas—both endocrine & exocrine gland

Liver—removes bilirubin (from RBC) as bilestores Fe & fat sol. ADEK vit.regulates sugar in blood (glycogen)makes plasma proteins, bile, urea (N) &cholesterol

XXX Jaundice, hepatitis (A,B & C), cirrhosis

Gallbladder—concentrates and stores bile fromliver cells

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Fig. 12.10

Fig. 12.11

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Fig. 12.7

Chemical Digestion

Macromolecules broken down by EnzymesDefine ENZYMESConditions: correct substrate

temperature-warmpH (optimal)

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Fig. 12.13

NUTRITION

Carbohydrates—ready source of energyComplex ones are better= bulk of food

Fiber--Insoluble—laxativelikeSoluble (oat bran) combo with bile

acids and cholesterolProtein—8 are essential (required)Lipids—less than 30% or plaque

(cause disease)(( olestra (fake fat)—can’t digest it))

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Fig. 12.15

Table 12.6

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Table 12.7

VITAMINS

Define—organic compound body uses for metabolic reasons—can make them allAntioxidants—free radicals made are unstable and carry an extra electron= damage (A, C, E)Vitamin D –by skin in sun, modified by kidneys and liver to calcitrol to absorb Ca

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Table 12.8

MINERALS

Macro—(Need more than 100 mg/day)Ca—need 1000-1500/ day or osteoporosis

vitamin D and Mg help to prevent itNa—need 500 mg/day BUT we often get

8X as much! (X blood pressure )+ P,K,Cl, Mg

Micro—(need less than 20mg/day)Zn,Fe,Cu,I,Se—specific necessary roles

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Fig. 12.18

Fig. 12.19

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Fig. 12.20

Eating Disorders

Obesity—(20% over ideal), mod,(40%+)severe (100%+)—on increasehormonal, metabolic, social

Bulemia—binge & purge (affect heart &kidneys & could lead to death

Anorexia—unreal fear of gaining weightactually starving; distorted brain

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