ANSWERS(RATED A+)
Side effect of another disorder - ANSWER- hormonal disorders:
hyperparathyroidism, exogenous glucocorticoids
Upper GI tract - ANSWEResophagus, stomach and small intestine
- digestion of food and fluid
- absorption of essential nutrients, vitamins and minerals
- alterations in upper GI function can cause indigestion, malabsorption, malnutrition,
or dehydration
Lower GI tract - ANSWERlarge intestine
- absorption of fluid and electrolytes
- alterations in lower GI function can cause dehydration, diarrhea or constipation
Stomach - ANSWER- primary function is to break down & digest food
- sphincters
Upper esophageal sphincter - ANSWERprevents aspiration of contents
Lower esophageal sphincter (LES) - ANSWERseparates gastric contents from
esophagus, gastric contents are acidic and can harm esophageal epithelium
Pyloric sphincter - ANSWERregulates movement of chyme out of stomach to
duodenum
Sphincter of Oddi - ANSWERregulates the movement of bile and pancreatic juice
from accessory organs
What are the 4 layers of the GI tract? - ANSWER1. mucosa
2. submucosa
3. muscularis
4. serosa
Small intestine - ANSWERmotility- peristalsis & segmentation
- villi and microvilli= increase surface area increasing absorptive cavity
Villi - ANSWERthousands of tiny fingerlike projections that contain cells, whose
functions are to release digestive enzymes, secrete mucus and absorb nutrients
Microvilli - ANSWERare located on the epithelial cells of the vili. This double set of
villi is known as the brush border
Villi and Microvilli - ANSWER- double the surface area significantly increasing the
absorptive capacity of the small intestine
, Large intestine - ANSWER- motility peristalsis & haustration
1. absorption of water and electrolytes (Na, CL, K)
2. Bacterial breakdown of proteins that were not digested or absorbed in the small
intestine. These resulting amino acids are broken down by bacteria, which leaves
ammonia. Ammonia is carried to the liver and converted to urea
3. bacteria metabolize bile salts and facilitate absorptions of bile
4. store feces until defecation
gastroesophageal reflux disease (GERD) - ANSWER- decreased closure of the
lower esophageal sphincter (LES) which allows acidic gastric contents to reflux up
into the esophagus and creates inflammation reaction
- decrease pressure at LES and increase pressure in stomach
Gastroesophageal Reflux Disease (GERD) causes - ANSWER- weak diaphragm or
circular muscle
- herniation
- delayed gastric emptying
- alcohol, smoking
- increased PNS
Gastroesophageal Reflux Disease (GERD) - ANSWER- acid of the stomach
damages the esophageal epithelium and imitates inflammation
- high acid contents causes erosion
- high acid environment changes squamous epithelium of esophagus to columnar
epithelium
- Barrett's esophagus
- can lead to esophageal cancer
- columnar epithelium is more resistant to acid
GI bleeding - ANSWER- hematemesis
- melena
- hematochezia
- occult blood
Hematemesis - ANSWER- vomiting blood
- red: current bleeding mostly from esophagus, medical emergency
- coffee grounds: blood from stomach that has mixed with stomach acid, then
vomited
Melena - ANSWERblack, tarry stool
- typically slow, chronic upper GI bleeding
- small intestine (PUD)
Hematochezia - ANSWER- bright, fresh blood from anus with stool
- lower GI bleeding from hemorrhoids, diverticulosis, colon cancer
Occult blood - ANSWER- small amount of blood, hidden in stool
- bleeding in any GI tract
- cannot see blood in stool but can test for it