Download Abdominal Viscera

Notes on Digestive System
Digestive tract is a “tube” (esophagus, stomach, small intestine, large intestine)
with outgrowths (liver, gallbladder, pancreas, vermiform appendix).
ESOPHAGUS
The esophagus ends in the abdomen and is continuous with the cardia of the
stomach.
STOMACH
Cardia: portion about the esophagus entrance
Fundus: the ballooning portion superiorly
Body: main part of stomach
Pylorus: terminal portion with thickened walls and sphincter opening into the
duodenum of the small intestine.
The sides of the stomach are the greater and lesser curvature.
 Fed by gastric artery (branch from celiac artery)
SMALL INTESTINE
 main function is absorption of nutrients
 Fed by superior mesenteric artery
Duodenum “12 fingers”
 first part of small intestine where most of digestion occur
 retroperitoneal (outside of abdominal cavity), with exception to first part
 “C” shaped
 hepatopancreatic ampullae – where pancreatic duct and bile duct come
together
 main pancreatic duct – buffers and enzymes from pancreas
 common bile duct – receives bile from gall bladder
Jejunum and ileum
 peritoneal (within abdominal cavity)
 jejunum is about 2/5 the total length of the rest of the small intestine
 ileum is the other 3/5
ileocecal valve: the junction between ileum and large intestine
 controls passage of intestinal contents
 heard as a loud gurgling sound
LARGE INTESTINE
 fed by inferior mesenteric artery
 main function is compaction of chime making it feces
taniae coli
- longitudinal smooth muscle bands
- create haustra during contraction
- contain appendices epiploicae - fatty appendages
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large intestine begins at the cecum
cecum continues in absorbing nutrients from chyme
cecum continues into the ascending colon
ascending colon:
 becomes retroperitoneal as it ascends
 ascends up the right side of the abdominal cavity
 turns at the right colic flexure and becomes the transverse colon
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Transverse colon:
 becomes peritoneal
 transverses inferiorly to the greater curvature of the stomach
 turns at the left colic flexure, and becomes the descending colon
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Descending colon:
 becomes retroperitoneal
 descends down the left side of the abdominal cavity
 When it becomes peritoneal, it is called the sigmoid colon
Sigmoid colon:
 terminates as the rectum lying directly on the sacrum
LIVER
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gland
nutrient processing center and detoxification center
peritoneal
fed by common hepatic artery
porta hepatica (root of liver):
location of the hepatic ducts (where bile is sent to the duodenum), hepatic
portal vein and hepatic arteries
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hepatic portal vein – brings blood from digestive tract to liver for
detoxification
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hepatic arteries – blood from descending aorta to liver
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common hepatic duct brings bile from the liver to duodenum (connects
with the cystic duct of the gallbladder)
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Hepatic veins (not part of root of liver) drains directly into the IVC from
liver
GALLBLADDER
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Stores and concentrates bile made in the liver
stimulated to contract after a meal
peritoneal
Cystic duct:
 brings bile from the gallbladder to the common hepatic duct
 now called common bile duct (cystic duct and common hepatic duct)
 empties into the duodenum
PANCREAS
 secretes digestive enzymes into the duodenum via pancreatic duct
 pancreatic duct joined by common bile duct at the hepatopancreatic
ampulla
 retroperitoneal
 sits in the curvature of the duodenum
SPLEEN
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NOT part of digestive system
Largest Lymphoid organ
Peritoneal (within body cavity)
Fed by splenic artery