Digestive System
ST120
Concorde Career College, San Antonio
Digestive System
Objectives:


Define the term digestion.
Describe the functions of the digestive system.
Digestive System
Objectives:


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 System
Objectives:


Describe the importance of adequate nutrition.
Describe the mechanism by which the digestive system
helps to maintain homeostasis.
Digestive System
Objectives:


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 System
Digestion
Mechanical, chemical, and enzymatic process by which
ingested food is converted into material suitable for use
at the cellular level.
Digestive System
Functions 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
Gallbladder
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
Endoscopic Procedures




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.
Colonoscopy
Intestinal Disorders

Diverticulosis: the condition of having diverticula


Enteritis: inflammation of the small intestine caused
by eating or drinking substances contaminated with
viral and bacterial pathogens


small pouch or sac occurring in the lining or wall of a
tubular organ such as the esophagus or colon
Gastroenteritis
Irritable bowel syndrome: (IBS) unknown cause with
symptoms that include cramping, abdominal pain,
bloating, constipation, and/or diarrhea.
Diverticular Disease
Some Procedures




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Gastrectmy
Cholecystectomy
Whipple pancreatectomy
Diverticulectomy
Ileectomy
Jejunectomy
Duodenectomy
Colectomy
Sigmoidectomy
Proctectomy