Digestive System Lecture Questions Flashcards
What are the main functions of the digestive system?
-Ingestion
-Mixing & propulsion
-Digestion
-Absorption
-Metabolism
-Defecation
What are the 2 main groups of organs in the digestive system?
-Alimentary canal/GI tract
-Accessory digestive
What is the alimentary canal? How long is it?
-GI tract
-Continuous tube from mouth to anal canal
-5-7 meters
What are the accessory digestive organs/structures?
-Teeth
-Tongue
-Salivary gland
-Liver
-Gallbladder
-Pancreas
How is the esophagus separated? What are the two areas of the esophagus called?
-It is separated by the diaphragm
-After it passes through the diaphragm, it is called the abdominal esophagus
-Before it passes through the diaphragm, it is called the thoracic esophagus
How is the peritoneal cavity subdivided?
-Greater sac
-Omental bursa (lesser sac)
What are the regions of the greater sac?
-Begins at the diaphragm
-Continues into pelvic cavity
What are the regions of the omental bursa/lesser sac?
-Located posterior to the stomach & liver
-Continues with the greater sac through the omental foramen
What level is the omental foramen encountered at?
T12
Where is the greater omentum located? What is its function?
-Attaches to the greater curvature of the stomach, the first part of the duodenum, and transverse colon
-Stores fat
-Contains arteries and accompanying veins (right and left gastro-omental vessels)
-Can block movement in abdominal cavity to help stop inflammation
-Will surround diseased structures
Where is the lesser omentum located? What is its function?
-Expands from the lesser curvature of the stomach and the first part of the duodenum to the inferior surface of the liver
-Acts as a ligament to suspend the stomach
What is the lesser omentum divided into?
-Hepatoduodenal ligament
-Hepatogastric ligament
What is the abdominal esophagus? Where does it emerge from? What structures pass through the diaphragm with it?
-Represents the short distal part of the esophagus located in the abdominal cavity
-Emerges through the right crus at T10
-Anterior and posterior vagus trunk passes with it
What regions is the stomach located?
-Epigastric
-Umbilical
-Left hypochondrium
What are the different portions of the stomach?
-Cardia
-Fundus
-Body
-Pyloric
-Greater curvature
-Lesser curvature
-Cardial notch
Where is the cardia region of the stomach?
Surrounds the opening of the esophagus
What is the cardial notch?
The angle between the esophagus and stomach
What is the fundus of the stomach?
The area above the level of the cardiac notch
What is the body of the stomach?
The largest part of the stomach
How do we get the feeling of being full?
When food reaches the level of the fundus, we feel full
What is the pyloric part of the stomach?
The distal end which is divided into the pyloric antrum and pyloric canal
What is the small intestine? What does it consist of
-The longest part of the GI tract
-Extends from the pyloric orifice to the ileocecal fold
-Duodenum (25 cm)
-Jejunum (2.5 m)
-Ileum (3.5 m)
-Large surface area for nutrient absorption
What is the duodenum? What is it divided into
-C-shaped structure adjacent to the head of the pancreas
-Above the level of the umbilicus
-Mostly secondary retroperitoneal except the first part
-Divided into 4 parts (superior, descending, inferior, ascending)
Where is the 1st/superior part of the duodenum located?
-To the right of the body of vertebra L1
-Anterior to bile duct
Where is the 2nd/descending part of the duodenum located? What is the significance of this part?
-From the neck of the gallbladder to the lower border of L3
-It is the entrance for the bile duct and pancreatic ducts
What is the sphincter called where the bile and pancreatic ducts enter the duodenum?
Sphincter of Oddi
Where is the 3rd/inferior part of the duodenum located?
Crosses the inferior vena cava, aorta, and vertebral column
Where is the 4th/ascending part of the duodenum located?
-Passes to the left of the aorta
-Across the upper border of L2
-Terminates at the duodenojejunal flexure
What is the ligament of Trietz?
The suspensory muscle of the duodenum
What region is the jejunum located? How is it different than the ileum?
-Mostly in the upper quadrant of the abdomen
-Slightly larger in diameter than the ileum
-Less prominent arterial arcades & longer vasa recta compared to those of the ileum
What region is the ileum located? What are unique characterisitcs of the ileum?
-Distal 3/5s of the small intestine
-Mostly in the right lower quadrant
-Has thinner walls, shorter vasa recta, more mesenteric fat, and more arterial arcades
What is the ileocecal fold? What is its function?
-Opening into the large intestine from the ileum
-Prevents reflux from the cecum to the ileum
-Regulates the passage of contents from the ileum to the cecum
Where is the large intestine located? How long is it? What is its function?
-Extends from the distal end of the ileum to the anal canal
-Absorbs fluids and salt from gut content
What are the different parts of the colon?
-Cecum
-Ascending colon
-Right colic flexure
-Transverse colon
-Left colic flexure
-Descending colon
-Sigmoid colon
-Rectum
-Anal canal
-Tenia coli
What is the tenia coli?
A muscle on the anterior, posterior, and lateral portions of the colon that contracts the colon to move contents through
What are the Haustra of the colon?
Sacculations of colon (does not contain muscle)
What are the omental appendices?
Fat tissue that is attached to the colon
How many sphincters does the anal canal have?
-Internal (involuntary)
-External (voluntary)
What regions is each part of the colon in?
-Cecum (R groin)
-Ascending (R flank)
-Right colic flexure (R hypochondrium)
-Transverse (epigastric & umbilical)
-Left colic flexure (L hypochondrium)
-Descending (L hypochondrium, L flank, L groin)
-Sigmoid (Pubic)
Where is the appendix located? What is it suspended by? What is its function?
-A narrow tube connected to the cecum
-Suspended by the mesoappendix
-It stores good bacteria, so when someone has diarrhea, it can restore good bacteria
What is the cause of appendicitis?
-The appendix gets closed off from the cecum
-Bacteria start to overproduce and it expands the appendix causing appendicitis
What is McBurney’s Point?
-Where the appendix is located if you wanted to palpate it
-Point 1/3 the way on a line from ASIS to umbilicus
How is pain felt when someone has appendicitis?
-Initially the pain begins as a central periumbilical pain that comes and goes
-After 6-10 hours, the pain localizes in the right iliac fossa and becomes constant
What portions of the colon are intraperitoneal and which are retroperitoneal?
-Ascending, descending colon, and rectum are secondary retroperitoneal
-Transverse and sigmoid and intraperitoneal
Where is the liver located?
Located in the right hypochondrium and epigastric regions
What are the functions of the liver?
-Produces bile (breaks down fat)
-Cholesterol metabolism
-Urea cycle
-Protein production (albumin)
-Clotting factor production
-Detoxification of blood
What is the largest visceral organ in the body?
The liver
What are the different surfaces of the liver?
-Diaphragmatic surface in the anterior, superior, and posterior directions
-Visceral surface in the inferior direction
What is the area called where the liver is in direct contact with the diaphragm?
Bare area
Where is the diaphragmatic surface of the liver located?
-Lies against the inferior surface of the diaphragm
-Associated with the subphrenic and hepatorenal recesses
What is the subphrenic recess?
Separates the diaphragmatic surface of the liver from the diaphragm & is divided into left and right areas by the Falciform ligament
What is the hepatorenal recess?
Part of the peritoneal cavity on the right side between the liver and the right kidney and right suprarenal gland
What is the visceral surface of the liver covered by?
Covered with visceral peritoneum except in the fossa for the gallbladder & at the porta hepatis/triad
Where does the portal vein drain blood from?
Drains blood from GI and sends it to the liver
What artery supplies blood to the liver?
Hepatic proper artery
What are the different lobes of the liver?
-Left
-Right
-Quadrate
-Caudate
What ligament separates the right and left lobes of the liver on the posterior side?
Ligamentum venosum
What ligament separates the left and quadrate lobes of the liver?
Ligamentum teres
What is the largest lobe of the liver?
Right
What is the caudate lobe bound to?
Bound on the left by the ligamentum venosum and on the right by the groove for the inferior vena cava
What is the quadrate lobe bound to?
Bound on the left by the ligamentum teres and on the right by the fossa for the gallbladder
What is the gallbladder? What does it consist of?
-A pear shaped sac lying on the visceral surface of the right lobe of the liver in a fossa between the right and quadrate lobes
-Body
-Fundus (lower portion)
-Neck (narrow upper portion)
What are the functions of the gallbladder?
Receives, concentrates, and stores bile from the liver
Where is the pancreas? What does it consist of?
-Located posterior to the stomach
-Extends from the duodenum on the right, to the spleen on the left
-Head
-Neck
-Tail (intraperitoneal and points towards spleen)
What is the function of the pancreas? How big is it?
-Produces and secretes digestive enzymes (digestive)
-Produces and secretes hormones like insulin and glucagon (endocrine)
-About 15 cm in length
