I. OVERVIEW OF THE DIGESTIVE SYSTEM

1. THE DIGESTIVE SYSTEM CONSISTS OF THE FOLLOWING :
   1. ORAL CAVITY

   2. PHARYNX

   3. ESOPHAGUS

   4. STOMACH

   5. SMALL INTESTINE

   6. LARGE INTESTINE

   7. ANUS

2. THE ACCESSORY ORGANS INCLUDE :
   1. SALIVARY GLANDS

   2. LIVER

   3. GALL BLADDER

   4. PANCREAS

3. THE G.I. TRACT CONSISTS OF FOUR LAYERS OR TUNICS :
   1. MUCOSAL
   2. SUBMUCOSA
   3. MUSCULARIS
   4. ADVENTITIA

4. THE MUCOSAL LAYER IS THE INNERMOST LAYER, IT CONSISTS OF
   1. MUCOUS EPITHELIUM :

      LOCATION	TYPE
      MOUTH, OROPHARYNX, ESOPHAGUS, ANUS	STRATIFIED SQUAMOUS
      REMAINDER OF THE G.I. TRACT	SIMPLE COLUMNAR

      
      

   2. LOOSE CONNECTIVE ( LAMINA PROPRIA )

   3. THIN MUSCLE LAYER ( MUSCULARIS MUCOSA )

5. SUBMUCOSA IS A THICK LAYER THAT CONSISTS OF :
   1. CONNECTIVE TISSUE

   2. NERVES

   3. BLOOD VESSELS

   4. SMALL GLANDS

   5. PLEXUS ( PARASYMPATHETIC NERVES )

6. THE MUSCULARIS LAYER CONSISTS OF : STOMACH OBLIQUE LAYER
   1. INNER CIRCULAR SMOOTH MUSCLE

   2. OUTER LONGITUDINAL SMOOTH MUSCLE

   3. EXCEPTIONS : UPPER ESOPHAGUS ( STRIATED ) AND STOMACH

   4. PLEXUS ( NERVE FIBERS AND PARASYMPATHETIC CELL BODIES (LOCATED BETWEEN TWO MUSCLE LAYERS

7. SEROSA - OUTER LAYER - SEROUS EPITHELIUM

8. PERITONEUM
   1. SIMPLE SQUAMOUS WITH CONNECTIVE TISSUES

   2. SEROUS

   3. VISCERAL PERITONIEUM (ORGANS SEROSA)

   4. SPACE BETWEEN PARIETAL AND VISCERAL POTENTIAL SPACE- FLUID FILLED ASCITES (A- SI- TEZ) LARGE ACC. FLUID

   5. MESENTERY- FOLDS BETWEEN ORGANS

   6. MESOCOLON- BINDS L.I. TO POSTERIOR WALL

   7. FALSIFORM LIGAMENT

   8. LESER AND GREATER OMENTUM (FATTY APRON)

   9. KIDNEY- PANCREAS- RETRO PERITONEAL

1. ORAL CAVITY
   1. LIPS AND CHEEKS ARE INVOLVED IN FACIAL EXPRESSION , MASTICATION AND SPEECH

   2. THE TONGUE IS INVOLVED WITH SPEECH, TASTE, MASTICATION AND SWALLOWING.

   3. THERE ARE 20 DECIDUOUS TEETH AND 32 PERMANENT TEETH
      1. TOOTH TYPES ARE :
         MOLARS
         CANINE
         PRE MOLARS
         INCISORS

         A TOOTH CONSISTS OF A :

         CROWN

         NECK

         ROOT

         COMPONENTS OF THE TOOTH INCLUDE:

         DENTIN

         PULP CAVITY ( NERVES, BLOOD VESSELS )

         CROWN

         TEETH ARE HELD IN THE ALVEOLI BY PERIDONTAL LIGAMENTS

         THE MUSCLES MASTICATION INCLUDE :

         MASSETER

         TEMPORAL

         MEDIAL PTERYGOID

         LATERAL PTERYGOID

         ROOF OF THE PALATE IS DIVIDED INTO THE HARD AND SOFT ALSO FOUND ARE THE UVULA AND FRENULUM

         SALIVARY GLANDS PRODUCE SEROUS AND MUCOSAL SECRETIONS

         THREE GLANDS ARE :

         PAROTID

         SUBMANDIBULAR

         SUBLINGUAL

         TONSILS INCLUDE : PHARYNGEAL, PALATINE, LINGUAL

         THE PHARYNX INCLUDES :

         NASOPHARYNX, OROPHARYNX, AND LARYNGOPHARYNX

         
         

         ESOPHAGUS

         1. THE ESOPHAGUS CONNECTS THE PHARYNX TO THE STOMACH

         2. THE UPPER AND LOWER ESOPHOGEAL SPINCTERS REGULATE MOVEMENT IN THE ESOPHAGUS

         3. THE ESOPHAGUS CONSISTS OF FOUR LAYERS
            FIBROUS LAYER - OUTER
            MUSCULAR LAYER - CIRCULAR AND LONGITUDINAL
            SUBMUCOSAL
            STRATIFIED SQUAMOUS EPITHELIUM

            THE ESOPHAGUS IS APP. 25 CM LONG, POSITION IS AS FOLLOWS

            LIES IN THE MEDIASTINUM

            ANTERIOR TO VERTEBRA

            POSTERIOR TO THE TRACHEA

            PASSES THROUGH THE ESOPHAGEAL HIATUS - OPENING

         STOMACH

         1. STRUCTURES OF THE STOMACH INCLUDE :
            1. OPENING INTO THE ESOPHAGUS (GASTROESOPHAGEAL) - CARDIAC

            2. OPENING INTO THE DUODENUM ( PYLORIC )

         2. THE WALL OF THE STOMACH INCLUDES :
            1. EXTERNAL SEROSA

            2. MUSCLE LAYER ( CIRCULAR, LONGITUDINAL, OBLIQUE )

            3. SUBMUCOSA

            4. SIMPLE COLUMNAR ( INTERIOR MUCOSAL )

         3. RUGAE ARE THE FOLDS IN THE STOMACH WHEN EMPTY

         4. GASTRIC PITS ARE THE OPENINGS INTO THE GASTRIC GLANDS

            1. . MUCOSAL NECK CELLS- MUCUS

            2. PARIETAL CELLS- HCL

            3. CHIEF CELLS- ZYMOGENIC- PEPSINOGEN

            4. ENDOCRINE CELLS

         5. GROSS ANATOMY OF THE STOMACH INCLUDE :
            1. FUNDUS

            2. CARDIAC REGION

            3. GREATER CURVATURE

            4. LESSER CURVATURE

            5. PYLORIC ANTRUM

            6. PYLORIC CANAL

            7. G. PYLORIC ORIFICE

         SMALL INTESTINE

         1. DIVIDED INTO THREE PORTIONS : TOTAL 20FT IN LENGTH
            1. DUODENUM- 10 INCHES

            2. JEJUNUM- 2/5

            3. ILEUM- 3/5

         2. THE WALL OF THE SMALL INTESTINE INCLUDES :
            1. EXTERNAL SEROSA

            2. MUSCULAR ( LONGITUDINAL, CIRCULAR )

            3. SUBMUCOSA

            4. SIMPLE COLUMNAR EPITHELIUM ( MUCOSAL )

         3. VILLI AND MICROVILLI INCREASE SURFACE AREA

         4. ABSORPTIVE, GOBLET, AND ENDOCRINE CELLS DEVELOP IN INTESTINAL GLANDS, CRYPTS OF LIEBERKUHN SECRETE DIGESTIVE ENZYME

         5. DUODENAL GLANDS PRODUCE MUCUS

         6. THE MUCOSA OF THE DUODENUM IS SIMPLE COLUMNAR OF THREE TYPES :
            1. ABSORPTIVE CELLS ( MICROVILLI )

            2. GOBLET CELLS ( PRODUCE MUCUS )

            3. ENDOCRINE CELLS ( REGULATORY HORMONES )

         7. THE SUBMUCOSA CONTAIN CELLS CALLED : BRUNNERS GLANDS THESE CELLS PRODUCE MUCUS

         8. STRUCTURE OF THE DUODENUM :
            1. CONTAINS A 180 DEGREE ARC

            2. GREATER AND LESSER DUODENAL PAPILLA GREATER : BILE AND PANCREATIC DUCTS JOIN THIS FORMS THE HEPATOPANCREATIC AMPULLA OPENING: HEPATOPANCREATIC AMPULLAR SPINCTER

            3. ACCESSORY PANCREATIC DUCT IS PRESENT IN MOST PEOPLE, FOUND AT LESSER PAPILLA

         9. THE JEJUNUM AND ILEUM ARE SIMILAR IN STRUCTURE TO THE DUODENUM, EXCEPT :
            1. GRADUAL DECREASE IN DIAMETER

            2. DECREASE IN THICKNESS

            3. DECREASE IN FOLDS AND VILLI

         10. THE JEJUNUM AND ILEUM ARE THE SITE OF MOST NUTRIENT ABSORPTION

         11. THE JUNCTION BETWEEN THE ILEUM AND THE LARGE INTESTINE IS THE ILEOCECAL JUNCTION ( SPHINCTER )

         LIVER

         1. THE LIVER IS THE LARGEST INTERNAL ORGAN OF THE BODY

         2. LOCATED IN THE RIGHT HYPOCHONDRIATIC AREA

         3. THE LIVER CONSISTS OF TWO MAJOR LOBES : LEFT AND RIGHT

         4. TWO MINOR LOBES : CAUDATE (RIGHT LOBE) AND QUADRATE

            A PORTA IS ON THE INFERIOR SURFACE OF THE LIVER, THIS IS THE AREA MANY BLOOD VESSELS, NERVES, AND DUCTS ENTER THE LIVER

         5. STRUCTURES AROUND THE PORTA INCLUDE :
            HEPATIC PORTAL VEIN
            HEPATIC ARTERY
            NERVE PLEXUS
            LYMPHATIC VESSELS
            TWO HEPATIC DUCTS ( TRANSPORT BILE )

            BRANCHING OF DUCTS INCLUDE :

            HEPATIC DUCTS ( 2 )

            COMMON HEPATIC DUCT

            CYSTIC DUCT ( FROM GALL BLADDER )

            COMMON BILE DUCT ( EMPTIES INTO DUODENUM)

            THE LIVER IS COVERED BY VISCERAL PERITONEUM, EXCEPT AT THE "BARE" AREA AT THE AREA OF THE DIAPHRAM

            SEPTA OF CONNECTIVE TISSUES BRANCH INTO THE LIVER

            THE SEPTA DIVIDE THE LIVER INTO LOBULES WITH PORTAL TRIADS ( 3 VESSELS HEPATIC PORTAL, HEPATIC ARTERY, DUCT )

            CENTRAL VEIN IN EACH LOBULE - CENTRAL VEINS FORM THE HEPATIC VESSELS WHICH EXITS ON THE POSTERIOR, SUPERIOR SURFACE

            THIS EMPTIES INTO THE INFERIOR VENA CAVA

            LIVER FUNCTIONS:

            CARBOHYDRATE METABOLISM- GLUCOSE TO/FROM GLYCOGEN

            NON-CARBOHYDRATES TO GLUCOSE

            LIPID METABOLISM- LIPOPROTEINS, PHOSPHOLIPIDS,

            CHOLESTEROL SYNTHESIS

            CONVERT CARBOHYDRATES AND PROTEINS TO FATS

            PROTEIN METABOLISM- DEAMINATION - SYN. UREA

            DETOX- SECRETES BILE

            HEPATIC FUNCTION:

            BILIRUBIN METABOLISM- 250-350 FORMED DAILY

            SOURCES: HEMOGLOBIN OF DEGENERATING RED BLOOD CELLS,

            RED BLOOD CELLS PRECURSOR IN MARROW,

            HEME PROTEINS OF LIVER AND OTHER TISSUE

            BILIRUBIN: INSOLUABLE IN WATER, TRANSPORTED PLASMA

            BOUND TO ALBUMIN, CANNOT CROSS CELL MEMBRANE

            (EXCEPT IN LIVER), NOT FOUND IN URINE

            CONJUGATION- FREE BILIRUBIN CONCENTRATED IN LIVER,

            COMBINED WITH GLUCURONIC ACID TO FORM CONJUGATED BILIRUBIN

            HEPATIC EXCRETION: SECRETED INTO BILE (CANAIS)

            BILIRUBIN CONVERTED INTO: STERCOBILINOGENS IN GUT UROBILINOGEN IN URINE

            JAUNDICE- YELLOWISH SKIN, SCLERS CAUSES- VARIOUS UNCONJUGATED HYPERBILIRUBINEMIA : INCREASED FORMATION, DECREASED HEPATIC UPTAKE, DECREASED CONJUGATION >CONJUGATED HYPERBILIRUBINEMIA : HEPATIC DISEASE, BILIARY OBSTRUCTION

         GALL BLADDER- CAPACITY 20-60 MILLILITERS

         12 HOURS OF SECRETION (450 ML) CAN BE STORED BECAUSE WATER AND SALTS ARE REMOVED BY ACTIVE AND OSMOSIS. CONCENTRATED 12-20 FOLD

         1. SMALL SAC ON THE INFERIOR SURFACE OF THE LIVER
         2. THREE TUNICS MAKEUP THE GALL BLADDER
            1. INNER MUCOSA WITH FOLDS (RUGAE)
            2. MUSCULARIS LAYER OF SMOOTH MUSCLE
            3. OUTER COVERING OF CONNECTIVE TISSUE
         3. GALL BLADDER CONNECTED TO THE COMMON BILE DUCT BY CYSTIC DUCT.

         4. SPHINCTER OF ODDI- RELAXES AND ALLOWS BILE TO FLOW TO THE DUODENUM.

         PANCREAS

         1. CONTAINS BOTH ENDOCRINE AND EXOCRINE TISSUE

         2. CONSISTS OF A BODY, HEAD, AND TAIL

         3. ENDOCRINE PORTION IS CALLED THE ISLETS OF LANGERHANS
            A. PRODUCE INSULIN (BETA) AND GLUCAGON (ALPHA)
            B. THESE CONTROL LEVELS OF BLOOD GLUCOSE AND AMINO ACIDS.

            EXOCRINE PORTIONS ARE COMPOSED OF:

            1. ACINI (PRODUCE DIGESTIVE ENZYMES)
            2. ACINI FORM LOBULES SEPARATED BY SEPTA
            3. INTERLOBAR DUCTS ATTACH TO PANCREATIC DUCT
            4. THIS JOINS THE COMMON HEPATIC DUCT AT THE HEPATOPANCREATIC AMPULLS.

            FROM PANCREAS, ARE SECRETED INACTIVE TRYPSINOGEN- (enterokinase) -> TRYPSIN CHYMOTRYPSINOGEN- (trypsin) -> CHYMOTRYPSIN PROCARBOXYPEPTIDASE- (trypsin) -> CARBOXYPEPTIDASE

         LARGE INTESTINE (COLON)

         1. CECUM IS AT THE PROXIMAL END

         2. AT THE END IS THE VERMIFORM APPENDIX (MCBURNEYS POINT)

         3. THE COLON IS APPROXIMATELY 1.5 TO 1.8 M LONG

         4. IS DIVIDED INTO THE FOLLOWING SECTIONS:
            A. ASCENDING COLON (ILIOCECAL SPHINCTER)
            B. HEPATIC FLEXURE
            C. TRANSVERSE COLON
            D. SPLENIC FLEXURE
            E. DESCENDING COLON
            F. SIGMOID (NOT IN CAT)
            G. RECTUM
            H. ANAL CANAL (ANUS)

            CIRCULAR LAYER OF MUSCLE IS COMPLETE

            LONGITUDINAL LAYER FORMS THE TENIAE COLI

            CONTRACTIONS OF THE TENIAE COLI FORM THE HASTURA

            ANAL CANAL CONTAINS THE INTERNAL AND EXTERNAL ANAL SPHINCTER

         CHARACTERISTICS OF G.I. WALL

         1. FUNCTIONS AS A SYNCYTIUM
            1. BUNDLES OF 1000+ FIBERS
            2. FIBERS ELECTRICALLY CONNECTED BY GAP JUNTIONS
            3. IMPULSE TRAVELS RAPIDLY FROM FIBER TO FIBER
            4. CONTINUAL SLOW ELECTRICAL ACTIVITY
            5. ALLOWS FOR TWO BASIC TYPES OF WAVES

            1. SLOW WAVES:
               1. ARE NOT ACTION POTENTIALS
               2. SLOW UNDULATING CHANGES IN THE MEMBRANE POTENTIAL
               3. OCCURS 3 PER MINUTE IN STOMACH AND 12 PER MINUTE IN SMALL INTESTINE

            2. SPIKES:
               1. TRUE ACTION POTENTIALS
               2. OCCUR AUTOMATICALLY WHEN RESTING POTENTIAL
               3. GOES BELOW 40 MILLI VOLTS= 1-10 SPIKES PER SECOND

         2. NEURAL CONTROL- ENTERIC NERVOUS SYSTEM
            1. FROM ESOPHAGUS TO ANUS
            2. LOCATED IN WALL OF GUT
            3. NEURONS NUMBER 100 MILLION- SAME NUMBER AS FOUND IN THE SPINAL CORD
            4. TWO PLEXUS OF NERVES
               1. MYENTERIC PLEXUS
               2. SUBMUCOSAL PLEXUS
            5. CONTROLS GASTRO-INTESTINAL MOVEMENT AND SECRETION

         3. PARASYMPATHETIC- PRE GANGLIONIC
            1. CRANIO-SACRAL
            2. INCREASE ACTIVITY OF ENTERIC SYSTEM
            3. SOME MAY BE INHIBITED

         4. SYMPATHETIC- POST GANGLIONIC
            1. ORIGIN- T5-L2, INHIBITS ACTIVITY
            2. THORACO-LUMBAR
            3. SLIGHT EXTENT INHIBITS BY NOREPINEPHRINE ON SMOOTH MUSCLE AND GREATER EXTENT ON ENTERIC SYSTEM

         5. NEURO-TRANSMITTERS
            1. ACETYLCHOLINE- PARASYMPATHETIC
            2. NOREPINEPHRINE- SYMPATHETIC
            3. CHOLECYSTOKININ- AT GALL BLADDER

         6. G.I. MOVEMENT
            1. PERISTALSIS:

            2. MIXING MOVEMENTS:
               1. CAUSED BY SPHINCTER WHEN CHYME REACHES SPHINCTER
               2. LOCAL CONSTRICTIVE CONTRACTIONS

         7. SWALLOWING- THREE PHASES
            1. VOLUNTARY: PUSHED UPWARD AND BACK BY THE TONGUE

            2. PHARYNGEAL STAGE: BOLUS OF FOOD STIMULATES SWALLOWING REFLEX
               1. TRACHEA CLOSED
               2. ESOPHAGUS OPENED
               3. FAST PERISTALTIC WAVE FORCES FOOD TO UPPER ESOPHAGUS (1-2 SECONDS)
               * ALMOST NEVER INITIATED BY DIRECT STIMULI TO SWALLOWING REGIONS FROM HIGHER AREAS

               * SWALLOWING CENTER INHIBITS RESPIRATORY CENTER (BREATHING INTERRUPTED)

               ESOPHAGEAL STAGE: TWO TYPES PERISTALSIS

               1. PRIMARY: CONTINUATION OF PERISTALSIS THAT BEGINS IN THE PHARYNX ESOPHAGUS TO STOMACH (8-10 SECONDS)
               2. SECONDARY: IF PRIMARY FAILS TO MOVE FOOD TO STOMACH, SECONDARY BEGINS ENTERIC NERVOUS SYSTEM IN ESOPHAGUS -- VAGAL AFFERENT AND MEDULLA -- VAGAL EFFERENT -- STIMULATE PERISTALSIS

         8. STOMACH EMPTYING
            1. INTENSE ANTRAL PERISTALTIC CONTRACTIONS
               1. USUALLY ANTRAL PERISTALSIS WEAK
               2. BECOMES VERY STRONG
               3. SIX TIMES MORE POWERFUL THAN USUAL
               4. PRINCIPLE FACTOR THAT CONTROLS EMPTYING

            2. PYLORUS
               1. PYLORIC CIRCULAR MUSCLE IN SPHINCTER
               2. REAMAINS SLIGHTLY TONIC
               3. SMALL OPENING ALLOWS WATER AND SMALL PARTICLES TO PASS

         9. REGULATION
            1. GASTRIC FOOD VOLUME
               1. STRETCH REFLEX INITIATED

            2. GASTRIN
               1. RELEASED FROM ANTRAL MUCOSA
               2. INCREASES ACID SECRETIONS
               3. INCREASES ACTIVITY OF PYLORIC PUMP

            3. CCK AND SECRETION- SLOWS EMPTYING
               1. ENTROGASTRIC REFLEX- DUODENUM TO STOMACH
                  DECREASE ANTRAL SLOWS STOMACH PROPULSIVE ACTION EMPTYING WHERE
                  DUODENUM IS FULL
                  CONTRACT PYLORIC SPHINCTER

            4. MOVEMENT IN SMALL INTESTINE
               1. TWO TYPES
               1. MIXING CONTRACTIONS
               2. PROPULSIVE CONTRACTIONS
                  PERISTALTIC RUSH-- FAST PROPULSION TO CECUM EXAMPLE: DIARRHEA

         10. FUNCTION OF ILEOCECAL VALVE
             1. PREVENTS BACK FLOW
             2. GASTRIN RELAXES SPHINCTER
             3. ONLY 1500 ML OF CHYME ENTER CECUM PER DAY
             4. ILEOCECAL SPHINCTER CONTROLLED BY REFLEX FROM CECUM

                CECUM DISTENDS -- SPHINCTER CONTRACTS -- ILEAL PERISTALSIS DECREASED

                *APPENDICITIS MAY CAUSE STOPPAGE OF FOOD THROUGH VALVES.

         11. MOVEMENTS OF THE COLON

             *TYPES OF PERISTALSIS IN SMALL INTESTINE IS RARE IN COLON.

             1. MIXING MOVEMENTS- HAUSTRATION
                1. TAENIA COLI CONTRACT PRODUCING HAUSTRATION
                2. FECAL MATERIAL DUG INTO AND ROLLED OVER EXPOSING ALL MATERIAL TO SURFACE OF LARGE INTESTINE

             2. PROPULSIVE- "MASS" MOVEMENT
                1. EXTRINSIC NERVES CONTROL MOST MASS MOVEMENT
                2. GASTRO-COLIC AND DUODENO-COLIC REFLEXES AFTER A MEAL

             3. DEFECATION
                1. INTERNAL SPHINCTER (SMOOTH MUSCLE) - INVOLUNTARY
                2. EXTERNAL SPHINCTER (STRIATED) - VOLUNTARY
                3. RECTUM NORMALLY EMPTY WHEN FECES ENTERS
                4. ENTERIC NERVOUS SYSTEM CAUSES CONTRACTION OF SPHINCTERS -- RELAX -- DEFECATION

             PART II : FUNCTION AND PHYSIOLOGY OF DIGESTIVE SYSTEM

             
             

             
             

             ENZYME OR FLUID	SOURCE	FUNCTION
             (SALIVA)	SALIVARY GLANDS
             SEROUS SALIVARY AMYLASE (PTYALIN) MUCUS	SUB MANIBULAR PARTOIDBR SUBLINGUAL	MOISTEN FOOD STARCH DIGESTION LUBRICATE FOOD
             (GASTRIC SECRETIONS)
             HCL PEPSINOGEN MUCUS	PARIETAL CELLS CHIEF CELLS MUCOSAL CELLS	ACTIVATE PEPSIN DIGEST PROTEIN PROTECTION
             (LIVER)
             BILE * BILE CONSISTS OF:	LIVER SODIUM GLYCHOLATE (BILE SALT) SODIUM TAUROCHOLATE (BILE SALT) FROM CHOLESTEROL CHOLESTEROL BILIVERDIN BILIRUBIN MUCUS FAT LECITHIN CELLS AND CELLULAR DEBRIS	EMULSIFY FATS LIPASES DIGEST

             (PANCREAS) STORED IN INACTIVE FORM IN ZYMOGEN GRANULES,
             SECRETED IN INACTIVE FORMS (PROTEIN ENZYME)

             
             

             
             

             TRYPSIN CHYMOTRYPSIN CARBOXYPEPTIDASE PANCREATIC AMYLASE PANCREATIC LIPASE RIBONUCLEASE DEOXYRIBONUCLEASE CHOLESTEROL ESTERASE BICARBONATE IONS	PANCREAS PANCREAS PANCREAS PANCREAS PANCREAS PANCREAS PANCREAS PANCREAS PANCREAS	DIGESTS PROTEIN DIGESTS PROTEIN DIGESTS PROTEIN DIGESTS CARBO. DIGESTS FAT DIGESTS RNA DIGESTS DNA FORMS CHOLESTEROL AND FREE FATTY ACID pH REGULATION
             (SMALL INTENTINE)
             ENZYME	SECRETED FROM	ACTION
             AMINOPEPTIDASE MUCUS PEPTIDASES AMYLASE ENTEROKINASE SUCRASE MALTESE ISOMALTASE LACTASE LIPASE	EPITHELIUM DUODENAL GLANDS GOBLET CELLS EPITHELIUM EPITHELIUM EPITHELIUM EPITHELIUM EPITHELIUM EPITHELIUM EPITHELIUM EPITHELIUM	SPILTS-POLYPEPTIDES PROTECTION HCL SPILTS AMINO ACIDS FROM POLYPEPTIDES DIGEST CARBO. ACTIVATES TRYPSIN SPLITS SUCROSE SPLITS MALTOSE SPILTS ISOMALTASE SPILTS LACTOSE SPILTS FATS

             GASTROINTESTINAL HORMONES

             HORMONE	SITE OF PRODUCTION	METHOD STIMULUS	SECRETORY EFFECT	MOBILITY EFFECT
             GASTRIN INCREASE MOTILITY)	GASTRIN/ENTERIC (STOMACH/DOU)	DISTENTION	INCRESE GASTERIC SEC.	INCREASE GASTRIC EMPT.
             SECRETIN (DECREASE MOTILITY, CAUSES RELEASE OF BICARBONATE, STIMULATES PANCREATIC JUICE AND BILE)	DUODENUM	ACIDITY	INHIBITS GASTERIC SEC.	INHIBITS MOTILITY
             C.C.K. 1. SLOWS PYLORIC PUMP 2. INCREASE SPHINCTER CONTRACTIONS 3. COMPETITIVE INHIBITOR TO BLOCK ACTION OF GASTRIN CHOL- BILE, CYST- BLADDER, KININ- TO MOVE	INTESTINE	FATTY ACID	STIMULATES PANCREATIC SEC. CONTRACT GALL BLADDER RELAX HEPATOPANCREATIC AMPULLAR SPHINCTER	INHIBITS GASTRIC SEC.
             GASTRIC INHIBITORY PEPTIDE	DUODENUM	FATTY ACID	INHIBITS PEPTIDE MOTILITY SLOWS RELEASE OF GASTRIC SECRETIONS
             VASOACTIVE INTESTINAL PEPTIDE (VIP)			STIMULATES INCREASED ELECTROLYTE PRODUCTION, INCREASE WATER IN LAMEN BY OSMOSIS STIMULATES PANCREAS
             PANCREOZYMIN * SAME AS CCK ZYMIN- ENZYME PRODUCER			STIMULATES PANCREAS

             SPHINCTER: CARDIAC (CLOSE), PYLORIC (OPEN), ILEOCECAL (OPEN)
             

             PART III : PHYSIOLOGY OF DIGESTION

             1. MASTICATION
                1. FOOD IS CHEWED
                2. MASTICATION REFLEX
                   1. PRESENCE OF FOOD IN THE MOUTH STIMULATES SENSORY RECEPTORS
                   2. REFLEX INTEGRATED IN THE MEDULLA OBLONGATA

             2. DEGLUTITION
                1. SWALLOWING OF FOOD BOLUS
                2. THREE PHASES:
                   1. VOLUNTARY STAGE
                   2. PHARYNGEAL PHASE- SWALLOWING RECEPTORS STIMULATED
                   3. ESOPHAGEAL PHASE

             3. STOMACH
                1. CEPHALIC PHASE
                   1. CEPHALIC STAGE IS THE SENSATIONS OF TASTE AND SMELL
                   2. THIS STIMULATES THE MEDULLA TOO INFLUENCE GASTRIC SECRETIONS
                   3. NERVE IMPULSE IS SENT VIA THE VAGUS NERVE TO THE STOMACH
                   4. THIS STIMULATES HCL, PEPSINOGEN, AND GASTRIN SECRETION

                2. GASTRIC PHASE
                   1. DISTENSION OF THE STOMACH STIMULATES GASTRIN SECRETIONS
                   2. ACTIVATES CNS AND LOCAL REFLEXES THAT PROMOTE SECRETION
                   3. PERISTALTIC WAVES PUSH THE MIXTURE TOWARD THE DUODENUM
                   4. TYPE OF MEAL DETERMINES HOW LONG FOOD WILL REMAIN

                   DUODENAL PHASE

                   1. AS CHYME ENTERS THE DUODENUM, IT STIMULATES THE ENTEROGASTRIC REFLEX
                   2. AS A RESULT FEWER PARASYMPATHETIC IMPULSES REACH THE STOMACH
                   3. PERISTALSIS IN STOMACH DECREASED
                   4. IF CHYME HAS A HIGH FAT CONTENT, CHOLESTOKININ WILL BE RELEASED FROM THE INTESTINAL WALL

                3. SMALL INTESTINE PHYSIOLOGY
                   1. LINED WITH VILLI
                   2. MOST NUMEROUS IN DUODENUM AND PROXIMAL PORTION OF JEJUNUM
                   3. EACH VILLUS CONTAINS:
                      1. LAYER OF SIMPLE COLUMNAR EPITHELIUM
                      2. A CORE CONTAINING BLOOD VESSELS
                      3. LACTEAL WITH A LYMPH CAPILLARY
                      4. NERVE

                   4. ABSORPTION OF THE SMALL INTESTINE
                      1. CARBOHYDRATE DIGESTION BEGINS IN THE MOUTH AND COMPLETED IN THE SAMLL INTESTINE. GLUCOSE ABSORBED INTO BLOOD
                      2. PROTEIN DIGESTION BEGINS IN THE STOMACH AND COMPLETED IN THE SMALL INTESTINE. AMINO ACIDS ABSORBED INTO BLOOD
                      3. FAT DIGESTION:
                         1. FATTY ACID MOLECULES ARE DISSOLVED AND DIFFUSE INTO THE VILLUS EPITHELIUM
                         2. THESE CELLS REMANUFACTURE FAT CELLS
                         3. ENCASED IN PROTEIN AND BECIME LIPOPROTEINS (CHYLOMICRONS)
                         4. LYMPH CARRIES THE CHYLOMICRONS TO BLOOD VESSEL
                         5. TRANSPORTED TO CAPILLARIES IN MUSCLE AND FAT TISSUE
                         6. THE ENZYME LIPOPROTEIN, LIPASE RELEASES FATTY ACIDS AND MONOGLYCERIDES FROM THE CHYLOMICRONS
                         7. THEY ENTER ADIPOSE TISSUE OR MUSCLE FOR STORAGE
                         8. REMAINDER OF THE CHYLOMICRON TRAVELS TO THE LIVER WHERE IT IS DESTROYED

                            
                            

                ***NOTE: SOME SHORT CHAIN FATTY ACIDS ARE DIRECTLY ABSORBED INTO THE BLOOD SYSTEM