1A-Basic Fxns of GI Flashcards
How long is the GI tube?
30ft!
What are the two linings of the GI tract?
- Epithelium 2.Muscle (smooth mainly, little bit of skeletal)
What are the three components of the Small Intestine? (in order of occurrence)
DOW JONES INDUSTRIAL! Duodenum, Jejunum, Ileum)
What are the five components of the Large Intestine? (in order of occurrence)
Cecum, Ascending, Transverse, Descending, and Sigmoid Colons
What is the MAIN function of the GI Tract?
To SEPARATE! the stuff we eat into nutrients and waste
What are the four mechanisms used by the GI tract to do its job?
1.Motility 2.Secretion 3.Digestion 4.Absorption
_________ in the walls of the GI tract maintains a constant low level of contractions known as ____.
Smooth Muscle….tone
What is another name/an example of smooth muscle “tone”?
Bowel Sounds!
______ is important in maintaining a steady pressure on the contents of the GI tract as well as in preventing its walls from remaining permanently stretched following distention.
Tone
Big Concept here! What are the three basic types of motility?
- Peristalsis 2. Segmentation 3. Tonic Contractions
Peristalsis is completely dependent on _________ contractions of smooth muscle.
involuntary
Which direction does peristalsis act?
Peristalsis propels contents FORWARD
Which type of motility promotes mechanical digestion of food?
Segmentation
Which type of motility facilitates absorption by exposing all portions of the intestinal contents to the absorbing surfaces of the GI tract?
Segmentation
Segmentation is completely dependent on ______ contractions of smooth muscle.
involuntary
What are the structures used in tonic contraction?
Sphincters
Tonic Contraction (sphincters) are completely dependent on _________ contractions of smooth muscle
involuntary
What are the 7 sphincters we discussed?
1.Upper Espohageal Sphincter (UES) 2.Lower Esophageal Sphincter (LES) 3.Pyloric 4.Ileocecal 5.Internal Anal Sphincter 6.External Anal Sphincter 7. Sphincter of Oddi
What regulates movement of contents of the common bile duct into the duodenum?
Sphincter of Oddi
What are the two VOLUNTARY control points in the GI tract?
1.mouth/UES 2.EXTERNAL anal sphincter
How much total fluid is produced by the body in a day?
9L (holy crap!)
How much saliva is produced daily?
1.5 L
How much gastric juice is produced daily?
2.5L
How much bile is produced daily?
0.5L
How much pancreatic juice is produced daily?
1.5L
How much intestinal secretion is produced daily?
1.0 L
How much MUCUS is produced daily?
2.0 L (WOW)
What is the underlying mechanism of chemical digestion?
Hydrolysis
What are the enzymes secreted by entercytes of the GI tract?
Brush Border Enzymes
What two locations does chemical digestion mainly occur?
Small Intestine & Stomach
Of the 9L of fluid produced daily, how much ends up in the stool?
Only 100ml (1.11%)
What are the two problems for the GI tract to solve?
1.Recycling 8.9L of fluid 2.Recognition of specific nutrients
The ________ is a slick serous membrane of the abdominopelvic cavity.
peritoneum
The _________ covers the external surfaces of most digestive organs and is continuous with the __________ that lines the walls of the abdominopelvic cavity.
visceral peritoneum…….parietal peritoneum
Between the two peritoneums is the ________, a slit-like space containing _________ secreted by the two membranes. The _____ fluid lubricates the mobile digestive organs, allowing them to glide easily across one another as they carry out their activities.
peritoneal cavity….peritoneal fluid….serous
What is inflammation of the peritoneum?
Peritonitis
What is the accumulation of peritoneal fluid?
Ascites (swelling) “Ass-eye-tee’s”
What is the apron of fat tissue hanging loosely from the transverse colon and the small intestine? What is the function of this structure?
the Greater Omentum…Fuel for organs (peristalsis, segmentation, and tonic contraction)
What is the peritoneal fold found in between the small intestine that anchors it to the posterior abdominal wall?
Mesentary
