chapter 12: the digestive system
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Chapter 12: The Digestive System. Chapter Objectives. Function of the digestive system. Digestive tract, functions of each part. Accessory organs and their role in digestion. Roots pertaining to the digestive system. Major disorders of the digestive system. - PowerPoint PPT PresentationTRANSCRIPT
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
Chapter 12: The Digestive System
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
Chapter ObjectivesChapter Objectives
Function of the digestive system.
Digestive tract, functions of each part.
Accessory organs and their role in digestion.
Roots pertaining to the digestive system.
Major disorders of the digestive system.
Medical terms used in reference to the digestive system.
Abbreviations used in referring to the gastrointestinal system.
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Key TermNormal Structure and Function
Key TermNormal Structure and Function
anus The distal opening of the digestive tract (root: an/o)
appendix An appendage; usually means the narrow tube of lymphatic tissue attached to the cecum, the vermiform (wormlike) appendix
bile The fluid secreted by the liver that emulsified fats and aids in their absorption (roots: chol/e, bili)
cecum A blind pouch at the beginning of the large intestine (root: cec/o)
colon The major portion of the large intestine; extends from the cecum to the rectum and is formed by ascending, transverse, and descending portions (root: col/o, colon/o)
common bile duct The duct that carries bile into the duodenum; formed by the union of the cystic duct and the common hepatic duct (root: choledoch/o)
duodenum The first portion of the small intestine (root: duoden/o)
enzyme An organic catalyst; speeds the rate of chemical reactions
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Key TermsNormal Structure and Function (cont’d)
Key TermsNormal Structure and Function (cont’d)
esophagus The muscular tube that carries food from the pharynx to the stomach.
feces The waste material eliminated from the intestine (adjective: fecal); stool
gallbladder A sac on the undersurface of the liver that stores bile (root: cholecyst/o)
hepatic portal system
A special pathway of the circulation that brings blood directly from the abdominal organs to the liver for processing (also called simply the portal system). The vessel that enters the liver is the hepatic portal vein (portal vein).
ileum The terminal portion of the small intestine (root: ile/o)
intestine The portion of the digestive tract between the stomach and the anus. It consists of the small intestine and large intestine. It functions in digestion, absorption, and elimination of waste (root: enter/o). The bowel (BOW-el)
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Key TermsNormal Structure and Function (cont’d)
Key TermsNormal Structure and Function (cont’d)
jejunum The middle portion of the small intestine (root: jejun/o)
lacteal A lymphatic capillary in a villus of the small intestine. Lacteals absorb digested fats into the lymph
large intestine The terminal portion of the digestive tract, consisting of the cecum, colon, rectum, and anus. It stores and eliminates undigested waste material (feces)
liver The large gland in the upper right part of the abdomen. In addition to many other functions, it secretes bile needed for digestion and absorption of fats (root: hepat/o)
lower esophageal sphincter (LES)
Muscle tissue at the distal end of the esophagus (gastroesophageal junction) that prevents stomach contents from refluxing into the esophagus. Also called the cardiac sphincter
mastication Chewing
mouth The oral cavity; contains the tongue and teeth. Used to take in and chew food, mix it with saliva, and move it toward the throat to be swallowed
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Key TermsNormal Structure and Function (cont’d)
Key TermsNormal Structure and Function (cont’d)
palate The roof of the mouth; the partition between the mouth and nasal cavity; consists of an anterior portion formed by bone, the hard palate, and a posterior portion formed of tissue, the soft palate (root: palat/o)
pancreas A large, elongated gland behind the stomach. It produces hormones that regulate sugar metabolism and also produces digestive enzymes (root: pancreat/o)
peristalsis Wavelike contractions of an organ's walls; moves material through an organ or duct
pharynx The throat; a common passageway for food entering the esophagus and air entering the larynx (root: pharyng/o)
pylorus The stomach's distal opening into the duodenum. The opening is controlled by a ring of muscle, the pyloric sphincter (root: pylor/o)
rectum The distal portion of the large intestine. It stores and eliminates undigested waste (root: rect/o, proct/o)
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Key TermsNormal Structure and Function (cont’d)
Key TermsNormal Structure and Function (cont’d)
saliva The clear secretion released into the mouth that moistens food and contains a starch-digesting enzyme (root: sial/o). Saliva is produced by three pairs of glands: the parotid, submandibular, and sublingual glands
sigmoid colon Distal S-shaped portion of the large intestine located between the descending colon and the rectum
small intestine The portion of the intestine between the stomach and the large intestine; comprised of the duodenum, jejunum, and ileum. Accessory organs secrete into the small intestine, and almost all digestion and absorption occur there
stomach A muscular saclike organ below the diaphragm that stores food and secretes juices that digest proteins (root: gastr/o)
uvula The fleshy mass that hangs from the soft palate; aids in speech production (literally “little grape”) (root: uvul/o)
villi Tiny projections in the lining of the small intestine that absorb digested foods into the circulation (singular: villus)
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Key TermsDisordersKey TermsDisorders
appendicitis Inflammation of the appendix
ascites Accumulation of fluid in the abdominal cavity; a form of edema. May be caused by heart disease, lymphatic or venous obstruction, cirrhosis, or changes in plasma composition.
biliary colic Acute abdominal pain caused by gallstones in the bile ducts
bilirubin A pigment released in the breakdown of hemoglobin from red blood cells; mainly excreted by the liver in bile
caries Tooth decay
celiac disease Inability to absorb foods containing gluten, a protein found in wheat and some other grains; caused by an excess immune response to gluten
cholecystitis Inflammation of the gallbladder
cholelithiasis The condition of having stones in the gallbladder; also used to refer to stones in the common bile duct
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Key TermsDisorders (cont’d)
Key TermsDisorders (cont’d)
cirrhosis Chronic liver disease with degeneration of liver tissue
Crohn disease A chronic inflammatory disease of the gastrointestinal tract usually involving the ileum and colon
diarrhea The frequent passage of watery bowel movements
diverticulitis Inflammation of diverticula (small pouches) in the wall of the digestive tract, especially in the colon
diverticulosis The presence of diverticula, especially in the colon
dysphagia Difficulty in swallowing
emesis Vomiting
fistula An abnormal passageway between two organs or from an organ to the body surface, such as between the rectum and anus (anorectal fistula)
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Key TermsDisorders (cont’d)
Key TermsDisorders (cont’d)
gastroenteritis Inflammation of the stomach and intestine
gastroesophageal reflux disease (GERD)
Condition caused by reflux of gastric juices into the esophagus resulting in heartburn, regurgitation, inflammation, and possible damage to the esophagus; caused by weakness of the lower esophageal sphincter (LES)
heartburn A warm or burning sensation felt behind the sternum and radiating upward. Commonly associated with gastroesophageal reflux. Medical name is pyrosis (pyr/o means “heat”)
hemorrhoids Varicose veins in the rectum associated with pain, bleeding, and sometimes prolapse of the rectum
hepatitis Inflammation of the liver; commonly caused by a viral infection
hepatomegaly Enlargement of the liver
hiatal hernia A protrusion of the stomach through the opening (hiatus) in the diaphragm through which the esophagus passes
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Key TermsDisorders (cont’d)
Key TermsDisorders (cont’d)
icterus Jaundice
ileus Intestinal obstruction. May be caused by lack of peristalsis (adynamic, paralytic ileus) or by contraction (dynamic ileus). Intestinal matter and gas may be relieved by insertion of a drainage tube
intussusception Slipping of one part of the intestine into another part below it. Occurs mainly in male infants in the ileocecal region). May be fatal if untreated for more than 1 day
jaundice A yellowish color of the skin, mucous membranes, and whites of the eye caused by bile pigments in the blood (from French jaune meaning “yellow”). The main pigment is bilirubin, a byproduct of erythrocyte destruction
leukoplakia White patches on mucous membranes, as on the tongue or cheeks, often resulting from smoking or other irritants; may be precancerous
nausea An unpleasant sensation in the upper abdomen that often precedes vomiting. Typically occurs in digestive upset, motion sickness, and sometimes early pregnancy
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Key TermsDisorders (cont’d)
Key TermsDisorders (cont’d)
occult blood Blood present in such small amounts that it can be detected only microscopically or chemically; in the feces, a sign of intestinal bleeding (occult means “hidden”)
pancreatitis Inflammation of the pancreas
peptic ulcer A lesion in the mucous membrane of the esophagus, stomach, or duodenum caused by the action of gastric juice
peritonitis Inflammation of the peritoneum, the membrane that lines the abdominal cavity and covers the abdominal organs. May result from perforation of an ulcer, rupture of the appendix, or infection of the reproductive tract, among other causes.
polyp A tumor that grows on a stalk and bleeds easily
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Key TermsDisorders (cont’d)
Key TermsDisorders (cont’d)
portal hypertension An abnormal pressure increase in the hepatic portal system. May be caused by cirrhosis, infection, thrombosis, or tumors
pyloric stenosis Narrowing of the opening between the stomach and the duodenum; pylorostenosis
regurgitation A backward flowing, such as the backflow of undigested food
splenomegaly Enlargement of the spleen
ulcerative colitis Chronic ulceration of the rectum and colon; the cause is unknown, but may involve autoimmunity
volvulus Twisting of the intestine resulting in obstruction. Usually involves the sigmoid colon and occurs most often in children and in the elderly. May be caused by congenital malformation, a foreign body, or adhesion. Failure to treat immediately may result in death
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Key TermsDiagnosis and Treatment
Key TermsDiagnosis and Treatment
anastomosis A passage or communication between two vessels or organs. May be normal or pathologic, or may be created surgically
barium study Use of barium sulfate as a liquid contrast medium for fluoroscopic or radiographic study of the digestive tract. Can show obstruction, tumors, ulcers, hiatal hernia, and motility disorders, among other things
cholecystectomy Surgical removal of the gallbladder
Dukes classification A system for staging colorectal cancer based on degree of penetration of the bowel wall and lymph node involvement; severity is graded from A to C
endoscopy Use of a fiberoptic endoscope for direct visual examination. GI studies include esophagogastroduodenoscopy, proctosigmoidoscopy (rectum and distal colon), and colonoscopy (all regions of the colon)
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Key TermsDiagnosis and Treatment (cont’d)
Key TermsDiagnosis and Treatment (cont’d)
ERCP Endoscopic retrograde cholangiopancreatography; a technique for viewing the pancreatic and bile ducts and for performing certain techniques to relieve obstructions. Contrast medium is injected into the biliary system from the duodenum and radiographs are taken
ostomy An opening into the body; generally refers to an opening created for elimination of body waste. Also refers to the operation done to create such an opening (see stoma).
stoma A surgically created opening to the body surface or between two organs (literally “mouth”)
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Supplementary termsNormal Structure and Function
Supplementary termsNormal Structure and Function
bolus A mass, such as the rounded mass of food that is swallowed
cardia The part of the stomach near the esophagus, named for its closeness to the heart
chyme The semiliquid partially digested food that moves from the stomach into the small intestine
defecation The evacuation of feces from the rectum
deglutition Swallowing
duodenal bulb The part of the duodenum near the pylorus; the first bend (flexure) of the duodenum
duodenal papilla The raised area where the common bile duct and pancreatic duct enter the duodenum; papilla of Vater (FA-ter)
greater omentum A fold of the peritoneum that extends from the stomach over the abdominal organs
hepatic flexure The right bend of the colon, forming the junction between the ascending colon and the transverse colon
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Supplementary TermsNormal Structure and Function (cont’d)
Supplementary TermsNormal Structure and Function (cont’d)
ileocecal valve A valvelike structure between the ileum of the small intestine and the cecum of the large intestine
mesentery The portion of the peritoneum that folds over and supports the intestine
mesocolon The portion of the peritoneum that folds over and supports the colon
papilla of Vater See duodenal papilla
peritoneum The serous membrane that lines the abdominal cavity and supports the abdominal organs
rugae The large folds in the lining of the stomach seen when the stomach is empty
sphincter of Oddi The ring of muscle at the opening of the common bile duct into the duodenum
splenic flexure The left bend of the colon, forming the junction between the transverse colon and the descending colon
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Supplementary TermsDisorders
Supplementary TermsDisorders
achalasia Failure of a smooth muscle to relax, especially the lower esophageal sphincter, so that food is retained in the esophagus
achlorhydria Lack of hydrochloric acid in the stomach; opposite is hyperchlorhydria
anorexia Loss of appetite. Anorexia nervosa is a psychologically induced refusal or inability to eat (adjectives: anorectic, anorexic)
aphagia Refusal or inability to eat; inability to swallow or difficulty in swallowing
aphthous ulcer An ulcer in a mucous membrane, as in the mouth
Barrett syndrome Lower esophageal ulcer resulting from chronic esophagitis, often with constriction caused by mucosal changes; may be premalignant. Also called Barrett esophagus
bruxism Clenching and grinding of the teeth, usually during sleep
bulimia Excessive, insatiable appetite. A disorder characterized by overeating followed by induced vomiting, diarrhea, or fasting
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Supplementary TermsDisorders (cont’d)
Supplementary TermsDisorders (cont’d)
cachexia Profound ill health, malnutrition, and wasting
cheilosis Cracking at the corners of the mouth, often caused by B vitamin deficiency (root cheil/o means “lip”)
cholestasis Stoppage of bile flow
constipation Infrequency or difficulty in defecation and the passage of hard, dry feces
dyspepsia Poor or painful digestion
eructation Belching
familial adenomatous polyposis (FAP)
A heredity condition in which multiple polyps form in the colon and rectum, predisposing to colorectal cancer
flatulence Condition of having gas or air in the GI tract
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Supplementary TermsDisorders (cont’d)
Supplementary TermsDisorders (cont’d)
flatus Gas or air in the gastrointestinal tract; gas or air expelled through the anus
hematemesis Vomiting of blood
irritable bowel syndrome (IBS)
A chronic stress-related disease characterized by diarrhea, constipation, and pain associated with rhythmic contractions of the intestine. Mucous colitis; spastic colon.
megacolon An extremely dilated colon. Usually congenital but may occur in acute ulcerative colitis.
melena Black tarry feces resulting from blood in the intestines. Common in newborns. May also be a sign of gastrointestinal bleeding.
obstipation Extreme constipation
pernicious anemia A form of anemia caused by the stomach’s failure to secrete intrinsic factor, a substance needed for the absorption of vitamin B12
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Supplementary TermsDisorders (cont’d)
Supplementary TermsDisorders (cont’d)
pilonidal cyst A dermal cyst in the sacral region, usually at the top of the cleft between the buttocks. May become infected and begin to drain.
thrush Fungal infection of the mouth and/or throat caused by Candida; appears as mucosal white patches or ulcers
Vincent disease Severe gingivitis with necrosis associated with the bacterium Treponema vincentii; necrotizing ulcerative gingivitis; trench mouth
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Supplementary TermsDiagnosis and Treatment
Supplementary TermsDiagnosis and Treatment
appendectomy Surgical removal of the appendix
bariatrics The branch of medicine concerned with prevention and control of obesity and associated diseases (from Greek baros, meaning “weight”)
Billroth operations Gastrectomy with anastomosis of the stomach to the duodenum (Billroth I) or to the jejunum (Billroth II)
gastric bypass surgery
Division of the stomach and anastomosis of its upper part to the small intestine (jejunum) to reduce nutrient absorption; used to treat morbid obesity. Other surgical methods are used for this purpose, including partition of the stomach with rows of staples (gastric stapling)
gavage Process of feeding through a nasogastric tube into the stomach
lavage Washing out of a cavity; irrigation
manometry Measurement of pressure; pertaining to the GI tract, measurement of pressure in the portal system as a sign of obstruction
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Supplementary TermsDiagnosis and Treatment (cont’d)
Supplementary TermsDiagnosis and Treatment (cont’d)
Murphy sign Inability to take a deep breath when fingers are pressed firmly below the right arch of the ribs (below the liver). Signifies gallbladder disease.
nasogastric (NG) tube
Tube that is passed through the nose into the stomach. May be used for emptying the stomach, administering medication, giving liquids, or sampling stomach contents.
parenteral hyperalimentation
Complete intravenous feeding for one who cannot take in food. Total parenteral nutrition (TPN).
percutaneous endoscopic gastrostomy (PEG) tube
Tube inserted into the stomach for long-term feeding
vagotomy Interruption of impulses from the vagus nerve to reduce stomach secretions in the treatment of gastric ulcer. Originally done surgically but may also be done with drugs.
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Supplementary TermsDrugs
Supplementary TermsDrugs
antacid Agent that counteracts acidity, usually gastric acidity
antidiarrheal Treats or prevents diarrhea by reducing intestinal motility or absorbing irritants and soothing the intestinal lining
antiemetic Agent that relieves or prevents nausea and vomiting
antiflatulent Agent that prevents or relieves flatulence
antispasmodic Agent that relieves spasm, usually of smooth muscle
emetic An agent that causes vomiting
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Supplementary TermsDrugs (cont’d)
Supplementary TermsDrugs (cont’d)
histamine H2 antagonist Drug that decreases secretion of stomach acid by interfering with the action of histamine at H2 receptors. Used to treat ulcers and other gastrointestinal problems. H2-receptor-blocking agent
laxative Promotes elimination from the large intestine. Types include stimulants, substances that retain water (hyperosmotics), stool softeners, and bulk-forming agents
proton-pump inhibitor (PPI)
Agent that inhibits secretion of stomach acid by blocking the transport of hydrogen ions (protons) into the stomach.
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AbbreviationsAbbreviationsBE Barium enema (for radiographic study of the colon)
BM Bowel movement
CBD Common bile duct
ERCP Endoscopic retrograde cholangiopancreatography
FAP Familial adenomatous polyposis
GERD Gastroesophageal reflux disease
GI Gastrointestinal
HAV Hepatitis A virus
HBV Hepatitis B virus
HCV Hepatitis C virus
HDV Hepatitis D virus
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Abbreviations (cont’d)Abbreviations (cont’d)
HEV Hepatitis E virus
HCl Hydrochloric acid
IBD Inflammatory bowel disease
IBS Irritable bowel syndrome
LES Lower esophageal sphincter
NG Nasogastric (tube)
N & V Nausea and vomiting
N/V/D Nausea, vomiting, and diarrhea
PONV Postoperative nausea and vomiting
PPI Proton pump inhibitor
TPN Total parenteral nutrition
UGI Upper gastrointestinal (radiograph series)
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DigestionDigestion
• Prepares food for cellular intake
– Nutrients must be small enough to be absorbed
– Nutrients broken down by mechanical and chemical means
• Occurs in digestive tract
• Food moved by peristalsis
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Digestive SystemDigestive System
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The Mouth to the StomachThe Mouth to the Stomach
• Digestion begins in mouth
– Mastication breaks up food
– Tongue, lips, cheek, and palate break up food and mix in saliva
– Moistened food passed:
• Into pharynx → through esophagus →into stomach
• Churning of stomach further breaks down food by:
– Mixing with enzyme pepsin and HCl
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The MouthThe Mouth
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Roots for the MouthRoots for the Mouth
Root Meaning Example Definition of Example
bucc/o cheek buccoversion turning toward the cheek
dent/o, dent/i tooth, teeth edentulous without teeth
odont/o tooth, teeth periodontics dental specialty that deals with the study and treatment of the tissues around the teeth
gingiv/o gum (gingiva) gingivectomy excision of gum tissue
gloss/o tongue glossoplegia paralysis (-plegia) of the tongue
lingu/o tongue orolingual pertaining to the mouth and tongue
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Roots for the Mouth (cont’d)Roots for the Mouth (cont’d)
Root Meaning Example Definition of Example
gnath/o jaw prognathous having a projecting jaw
labi/o lip labium lip or liplike structure
or/o mouth circumoral around the mouth
stoma, stomat/o
mouth xerostomia dryness (xero-) of the mouth
palat/o palate palatine pertaining to the palate (also palatal)
sial/o saliva, salivary gland, salivary duct
sialogram radiograph of the salivary glands and ducts
uvul/o uvula uvulotome instrument (-tome) for incising the uvula
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Roots for the Digestive Tract(Except for the Mouth)
Roots for the Digestive Tract(Except for the Mouth)
Root Meaning Example Definition of Example
esophag/o esophagus esophageal* pertaining to the esophagus
gastr/o stomach gastroparesis partial paralysis (paresis) of the stomach
pylor/o pylorus pyloroplasty plastic repair of the pylorus
enter/o intestine dysentery infectious disease of the intestine
duoden/o duodenum duodenostomy surgical creation of an opening into the duodenum
* Note addition of e before –al.
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Roots for the Digestive Tract(Except for the Mouth)
Roots for the Digestive Tract(Except for the Mouth)
Root Meaning Example Definition of Example
jejun/o jejunum jejunectomy excision of the jejunum
ile/o ileum ileitis inflammation of the ileum
cec/o cecum cecoptosis downward displacement of the cecum
col/o, colon/o
colon coloclysis irrigation (-clysis) of the colon
sigmoid/o sigmoid colon
sigmoidoscope an endoscope for examining the sigmoid colon
rect/o rectum rectocele hernia of the rectum
proct/o rectum proctopexy surgical fixation of the rectum
an/o anus perianal around the anus
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The Small IntestineThe Small Intestine
• Partially digested food passes through pylorus into duodenum
• Digestion completed after passing through other parts of small intestine (jejunum and ileum)
• Digested nutrients absorbed into circulation– Aided by villi
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The Large IntestineThe Large Intestine
• Undigested food, water, digestive juices
• Begins with cecum
• Colon twists and turns:
– Ascending colon
– Transverse colon
– Descending colon
• Water reabsorbed, feces formed
• Waste material passes into sigmoid colon
• Waste stored in rectum; eliminated through anus
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Accessory OrgansAccessory Organs
• Salivary glands
– Secretes enzyme that begins digestion of starch
• Liver
– Secretes bile to break down fats
• Gallbladder
– Bile stored here until needed
• Pancreas
– Produces mixture of digestive enzymes
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Accessory OrgansAccessory Organs
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Roots for the Accessory OrgansRoots for the Accessory Organs
Root Meaning Example Definition of Example
hepat/o liver hepatocyte a liver cell
bili bile biliary pertaining to the bile or bile ducts
chol/e, chol/o bile, gall cholestasis stoppage of bile flow
cholecyst/o gallbladder cholecystogram radiograph of the gallbladder
cholangi/o bile duct cholangioma cancer of the bile ducts
choledoch/o common bile duct
choledochal pertaining to the common bile duct
pancreat/o pancreas pancreatotropic acting on the pancreas
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Clinical Aspects of the Digestive SystemClinical Aspects of the Digestive System• Infection
– Can be caused by variety of organisms
• Ulcers
– Lesion of skin or mucous membrane
– Marked by inflammation or tissue damage
– Can be diagnosed by:
• Endoscopy
• Barium study (Radiography with contrast medium)
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CancerCancer
• Colon and rectum most likely affected area
• Risk factors:
– Diet low in fiber, high in fat
– Heredity
– Chronic inflammation of colon (colitis)
• Polyps often become cancerous
• Symptom: bleeding into intestine
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Cancer (cont’d)Cancer (cont’d)
• Internal observations performed with endoscopes
• Treatment may require surgical removal of portion of GI tract
– May create a stoma for waste elimination
– Surgery is called –ostomy, with root named for involved organ (e.g. colostomy)
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ObstructionsObstructions
• Hernia
– Protrusion of organ through abnormal opening
• Pyloric stenosis
– Opening between stomach and small intestine too narrow
• Intussusception
– Slipping of part of intestine into part below
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Obstructions (cont’d)Obstructions (cont’d)
• Volvulus
– Intestinal twisting
• Ileus
– Intestinal obstruction caused by lack of peristalsis
• Hemorrhoids
– Varicose veins in the rectum
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Gastroesophageal Reflux DiseaseGastroesophageal Reflux Disease
• Reflux of gastric juices caused by weakness at gastroesophageal junction
• Heartburn likely to occur after meals, when lying down, with hiatal hernia, and pregnancy
• Treatment:
– Weight loss
– Elevate head
– Avoidance of irritating foods
– Drugs
– Surgery
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Inflammatory Intestinal DiseaseInflammatory Intestinal Disease
• Crohn disease
– Chronic inflammation of intestinal wall segments, usually ileum
– May causes, pain, diarrhea, abscess, formation of fistula
• Ulcerative colitis
– Continuous inflammation of colon lining, usually rectum
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Inflammatory Intestinal Disease (cont’d)Inflammatory Intestinal Disease (cont’d)
• Celiac disease
– Inability to absorb gluten
• Diverticulitis
– Many small pouches in wall of intestine
– Attributed to diet low in fiber
– If pouches collect waste and bacteria, leads to diverticulitis
– Treated with diet improvement, stool softeners, drugs to reduce motility
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HepatitisHepatitis
• Inflammation of the liver
• More than six types of viral infections
– Hepatitis A
• Spread by fecal-oral contamination
– Hepatitis B
• Spread by blood and other body fluids
– Hepatitis C
• Spread through blood or close contact to infected person
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Hepatitis (cont’d)Hepatitis (cont’d)
– Hepatitis D
• Highly pathogenic, only affects those with Hepatitis B
– Hepatitis E
• Spread by contaminated food and water
– Hepatitis G
• Spread through contact with blood of infected person
– Vaccines available for Hepatitis A and B
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CirrhosisCirrhosis• Chronic liver disease mainly caused by excess consumption of alcohol
• Characterized by:
– Hepatomegaly
– Edema
– Ascites
– Jaundice
• As it progresses:
– Splenomegaly
– Internal bleeding
– Brain damage
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GallstonesGallstones
• Cholecystitis
– Inflammation of gallbladder
• Cholelithiasis
– Presence of stones in gallbladder
– Usually associated with cholecystitis
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Gallstones (cont’d)Gallstones (cont’d)
• Diagnosed by:
– Ultrasonography
– Radiography
– Endoscopic retrograde cholangiopancreatography
• Treatment may involve:
– Drugs to dissolve stones
– Cholecystectomy
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PancreatitisPancreatitis
• Inflammation of pancreas
• May result from:
– Alcohol abuse
– Drug toxicity
– Bile obstruction
– Infections
– Other causes
• Disease often subsides with only treatment of symptoms
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PretestPretest
1. An organic catalyst is a(n):
(a) sugar
(b) nucleic acid
(c) saliva
(d) enzyme
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
1. An organic catalyst is a(n):
(a) sugar
(b) nucleic acid
(c) saliva
(d) enzyme
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
2. The organ that carries food from the pharynx to the stomach is the:
(a) trachea
(b) larynx
(c) esophagus
(d) intestine
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
2. The organ that carries food from the pharynx to the stomach is the:
(a) trachea
(b) larynx
(c) esophagus
(d) intestine
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
3. The word root for the stomach is:
(a) gastr/o
(b) hepat/o
(c) ren/o
(d) cardi/o
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
3. The word root for the stomach is:
(a) gastr/o
(b) hepat/o
(c) ren/o
(d) cardi/o
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
4. The main portion of the large intestine is the:
(a) stomach
(b) appendix
(c) colon
(d) rectum
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
4. The main portion of the large intestine is the:
(a) stomach
(b) appendix
(c) colon
(d) rectum
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
5. The word root enter/o refers to the:
(a) intestine
(b) heart
(c) kidney
(d) gallbladder
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
5. The word root enter/o refers to the:
(a) intestine
(b) heart
(c) kidney
(d) gallbladder
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
6. The wavelike action that moves substances through an organ is called:
(a) pulmonary
(b) peristalsis
(c) parotid
(d) mastication
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
6. The wavelike action that moves substances through an organ is called:
(a) pulmonary
(b) peristalsis
(c) parotid
(d) mastication
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
7. The process of moving digested nutrients from the intestine into the circulation is called:
(a) digestion
(b) egestion
(c) absorption
(d) lymphedema
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
7. The process of moving digested nutrients from the intestine into the circulation is called:
(a) digestion
(b) egestion
(c) absorption
(d) lymphedema
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
8. The organ that secretes bile is the:
(a) kidney
(b) spleen
(c) liver
(d) stomach
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
8. The organ that secretes bile is the:
(a) kidney
(b) spleen
(c) liver
(d) stomach
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
9. Cholecystitis is inflammation of the:
(a) gallbladder
(b) throat
(c) diaphragm
(d) small intestine
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
PretestPretest
9. Cholecystitis is inflammation of the:
(a) gallbladder
(b) throat
(c) diaphragm
(d) small intestine