Digestive System

ST120Concorde Career College, Portland

Digestive SystemObjectives:

Define the term digestion. Describe the functions of the digestive

system.

Digestive SystemObjectives:

List and identify the structures of the digestive system and describe the function of each.

List and identify the accessory structures of the digestive system and describe the function of each.

Digestive SystemObjectives:

Describe the importance of adequate nutrition.

Describe the mechanism by which the digestive system helps to maintain homeostasis.

Digestive SystemObjectives:

Describe common diseases, disorders, and conditions of the digestive system including signs and symptoms, diagnosis, and available treatment options.

Demonstrate knowledge of medical terminology related to the digestive system verbally and in the written form.

Digestive SystemDigestion

Mechanical, chemical, and enzymatic process by which ingested food is converted into

material suitable for use at the cellular level.

Digestive SystemFunctions of the Digestive System

Digestion

Absorption

Note: The digestive tract is also referred to as the alimentary tract or canal.

Wall of the Digestive Tract

From outermost to innermost Serosa (visceral

peritoneum) Muscularis (2

layers) Submucosa Mucosa

Peritoneum

Parietal - lines the abdominal cavity

Visceral - covers the organs

Mesentery

Fanlike peritoneal fold that is attached posteriorly and attaches to the small intestine

Contains blood vessels, nerves, and lymphatic structures

Mesocolon

Fanlike peritoneal fold that is attached posteriorly and attaches to the large intestine

Contains blood vessels, nerves, and lymphatic structures

Diseased Mesocolon

Greater Omentum

Flap-like peritoneal structure containing fat that extends from the greater curvature of the stomach to the pelvis

Torsion of the Greater Omentum

Lesser Omentum

Extends between the lesser curvature of the stomach and the liver

Digestive Organs

Organs of the digestive tract (pathway)

Accessory organs

Main Structures of the Digestive Tract

Mouth Pharynx Esophagus Stomach Small

Intestine Large

Intestine

Oral Cavity

Functions: Ingestion Prepare ingested items for digestion Begin digestion of starch

Oral Cavity

Teeth

Deciduous Permanent Structure

Mastication & Deglutition

Mastication Salivary glands Muscles

Deglutition Muscles

Salivary Duct Stone

Pharynx and Esophagus

Convey ingested items to the stomach

Deglutition

Note movement of food bolus

Impacted Esophageal Food Bolus

Stomach

Divisions Curvatures Sphincters Muscles Rugae Gastric

Juices Chyme

Rugae

Gastrectomy Specimen

Stomach Interior

Goblet Cells - Produce mucus

Parietal Cells - Produce hydrochloric acid

Chief Cells - Produce pepsin

Small Intestine

Duodenum Jejunum Ileum

Villi

Large Intestine

Cecum Ileocecal valve Vermiform appendix

Ascending colon Transverse colon Descending colon Sigmoid colon Rectum Anus

Colectomy Specimen

Colectomy Specimen (Opened)

Rectum and Anus

Rectum Valves of Houston

Anus Anal columns Anal sinuses Anal valves Internal sphincter External sphincter

Accessory Structures

Liver Gallbladde

r Pancreas

Liver

Largest glandular organ in the body

RUQ Two main lobes

(right and left) Two small inferior

lobes on the right

Gallbladder

Located on the inferior surface of the liver

Stores bile

Biliary Tree

Biliary Tree

Pancreas

Endocrine gland Exocrine gland Extends from

the duodenum (head) to the spleen (tail)

Digestion

Breakdown of foods into usable substances

Esophagogastroduodenoscopy: visualization of the esophagus, stomach, and duodenum

Colonoscopy: visualization of the inner surface of the entire colon from the rectum to the cecum.

Sigmoidoscopy: visualization of the sigmoid colon

Capsule endoscopy: a tiny video camera in a capsule that the pt. swallows. For 8 hrs it passes through the small intestine and transmits images of the walls of the small intestine.

Endoscopic Procedures

Colonoscopy

Diverticulosis: the condition of having diverticula small pouch or sac occurring in the lining or wall of

a tubular organ such as the esophagus or colon Enteritis: inflammation of the small intestine

caused by eating or drinking substances contaminated with viral and bacterial pathogens Gastroenteritis

Irritable bowel syndrome: (IBS) unknown cause with symptoms that include cramping, abdominal pain, bloating, constipation, and/or diarrhea.

Intestinal Disorders

Diverticular Disease

Gastrectmy Cholecystectomy Whipple pancreatectomy Diverticulectomy Ileectomy Jejunectomy Duodenectomy Colectomy Sigmoidectomy Proctectomy

Some Procedures