Gastrointestinal Tract Chapter 17 Gastrointestinal Tract

Structure & Function Gastrointestinal (GI) tract is concerned with: Made up of the:

Cleft Lip & Cleft Palate Embryologically, the face and palate form when proliferating cell masses merge to form: Multifactorial inheritance leads to developmental defects Cleft lip is a defect in the: Cleft palate is a defect in the:

Types of cleft lip and palate abnormalities viewed from below Fig 17-1

Cleft Lip and Palate

Tooth Development Tooth is anchored in the jaw by connective tissue Each tooth consists of: Dentine which is: Enamel which covers: Pulp cavity in center of the tooth which contain: Root is embedded in the: Covered by a small layer of bone-like material called: Tooth is anchored in the jaw by connective tissue

Dental caries Infectious disease of teeth due to bacteria on tooth surface Plaque is made up of: Predispose to: Caused by bacteria feeding on food materials such as sugars & starches Acids are released that: Bacteria invade forming: If left untreated, bacteria invade the pulp resulting in: Spread of the infection to the bone surrounding the dental root results in:

Dental caries: Prevention & Treatment Incidence of tooth decay can be reduced by: Dental caries are treated by:

Periodontal disease Bacteria and debris collect around the base of the teeth Inflammation only affecting the gums surrounding the root is called: Inflammation and infection between the gums and teeth is called: Infection may spread into the tooth socket causing:

Diseases of the Esophagus The esophagus is a muscular tube extending from the: Upper sphincter relaxes to allow: Lower esophageal sphincter (cardiac sphincter) relaxes to allow:

Diseases of the Esophagus Incompetent Cardiac Sphincter Allows for: Lining of esophagus becomes: Called: Long-term reflux can lead to bleeding, ulceration, and scarring of esophagus In some individuals the lining becomes metaplastic which increases the risk of developing adenocarcinoma Treatment consists of:

Diseases of the Esophagus Gastric Mucosal Tears Occur in the gastroesophageal junction due to: Can bleed extensively Most often follows:

Gastric mucosal tear caused by retching and vomiting Fig. 17-6

Gastritis Is inflammation of the: Acute gastritis is a: May be complicated by: ulceration & bleeding Most caused by: Chronic gastritis: Produces compounds that break down: Spreads via person-to-person through: Increased risk of:

Peptic ulcer Is a chronic ulcer that usually involves the: Results from: H. pylori infection predisposes a person to ulceration Produce pain which is usually relieved by: Complications: Usually treated with: Antacids: Antibiotic therapy:

Inflammatory Diseases of the Intestines Enteritis: Colitis: Gastroenteritis:

Inflammatory Diseases of the Intestines Acute enteritis is usually caused by: Are generally of: Symptoms include: Chronic enteritis is characterized by periodic flare-ups manifested by: Patients may also have inflammation of other tissue Two main diseases appear to be autoimmune: Crohn Disease Ulcerative colitis

Inflammatory Diseases of the Intestines Crohn disease is: Distal ilium is frequently involved but may involve any part of small intestine & possibly the colon Thickening & scarring of intestinal wall can narrow lumen which impedes: Treatment: drugs and possible surgical resection of affected part of bowel

Inflammatory Diseases of the Intestines Ulcerative colitis: Usually begins in the: Mucosa may bleed excessively: Treatment: symptomatic and supportive measures, antibiotics, corticosteroids to control flare-ups, immunosuppressive drugs, surgical resection

Inflammatory Diseases of the Intestines Appendicitis occurs when the opening to the appendix becomes blocked by: Normal secretions become blocked and create: This leads to compression of: Bacteria invade the wall of the appendix causing: Symptoms include: Treatment:

Eating Disorders Anorexia Nervosa is a condition in which a person has a: Lose weight by: May also: Most often occurs in: Many bodily processes such as menstrual cycle are disrupted and may lead to death if not treated Treatment requires:

Eating Disorders Bulemia nervosa is characterized by: Weight is usually maintained leaving family and friends: Risk of gastric mucosa tears from retching and vomiting Dental problems and metabolic alkalosis from vomiting-induced loss of gastric acid Treatment similar to treatment of anorexia nervosa

Diseases of the Colon Diverticulosis is a condition of diverticula which are: Usually occurs in: Small hard stools require increase intraluminal pressure to: High pressure predisposes someone to the condition Diverticulitis occurs when:

Diverticulosis of colon Diverticulosis of colon. Exterior of colon, illustrating several diverticula projecting through the wall of the colon. Fig. 17-16 A

Diverticula of colon demonstrated by injection of barlum contrast material into colon (barium enema) Fig. 17-16 C

Intestinal Obstruction A person is said to have an intestinal obstruction if: Always considered as: Severity of symptoms depends on: High intestinal obstruction occurs in: Symptoms include: Low intestinal obstruction occurs in:

Intestinal Obstruction Hernia is: Inguinal hernia is common in: loop of small bowel protrudes through a weak area in inguinal ring and may descend into: Umbilical hernia occurs when:

Intestinal Obstruction Hernia Reducible hernia: Incarcerated hernia: Strangulated hernia:

Inguinal Hernia

Umbilical hernia, infant Fig 17-20 Inguinal hernia, bilateral, extending into scrotum Fig 17-19

Intestinal Obstruction Volvulus is: Most often occurs in: Intussusception is: a telescoping of a segment of bowel into adjacent segment

Volvulus and Intussusception

Intussusception resulting from a colon tumor Fig. 17-24

Fig. 17-24 Volvulus A. Rotary twisting of sigmoid colon on its mesentery B. Obstruction of colon and interruption of blood supply

Hemorrhoids Are varicose veins of: Development is predisposed by: Symptoms are relieved by: Internal hemorrhoids occur in: May erode and bleed, become thrombosed, or prolapse External hemorrhoids occur in: May become thrombosed, causing discomfort

Hemorrhoids

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