Digestive System Flashcards
digestion
the breakdown from complex to simple; from mouthful to molecule via mechanical and chemical actions
absorption
the uptake of nutrients into the body which must be broken down to the level of molecules to be absorbed
polyp
abnormal growth of tissue projecting from a mucous membrane on the inside of the colon, may be cancerous
haustra
small pouches caused by sacculation which give the colon its segmented appearance
taeniae coli
3 separate longitudinal ribbons of smooth muscle on the outside of the ascending, transverse, descending and sigmoid colon
peristalsis
rhythmic muscular waves if contraction by which the alimentary canal moves its contents toward the rectum
diverticulosis (tics)
pouches on the wall of the colon which may never be discovered unless inflamed
diverticulitis
inflammation of pouches on the wall of the colon
lacteals
numerous small intestinal lymph carrying vessels that convey chyle from the intestine to lymphatic circulation and thereby to the thoracic duct
fat soluble nutrients
nutrients that reside in the bodys fatty tissue and liver and used by the body as needed
water soluble nutrients
nutrients that dissolve in water, not generally stored in the body
functions of saliva
enzymes that begin carbohydrate digestion
forms bolus,
lubricates passageway to ease passage of bolus
maintain alkaline pH in the mouth
functions of pharynx
passageway for air/food (naso - air only; oro & laryngo - air and food
functions of esophagus
parastaltic action which carries bolus from laryngopharynx to stomach
functions of stomach
storage of food; chemical and mechanical digestion
chemical digestion
secretions of acids/enzymes
mechanical digestion
churning/peristalsis
functions of small intestine
digestion - from bolus to molecules (enzymes)
absorption - nutrients
functions of large intestine
absorption of water and elimination of waste product
functions of gall bladder
storage of bile, concentration of bile, evacuate of bile as needed during digestion
functions of bile
elimination of waste pigment bilirubin
emulsifier
functions of pancreas
exocrine - through a duct - digestive enzymes and alkaline fluids
endocrine - direct in blood - insulin and glucagon
portal circulatory system
circulation of blood through larger vessels from the capillaries of one organ to those of another; from gastrointestinal tract and spleen through the portal vein to the liver
fistula
abnormal connection between and organ, vessekm or intestine and another structure; usually caused by surgery but also from infection/inflammation
GERD esophagitis and appearance
failure of cardiac sphincter, reflux of stomach contents (& acids) into the esophagus
GERD appearance
streaked appearance
Infectious esophagitis
inflammation of esophagus due to infection (candida - fungal; herpes - viral)
infectious esophagitis appearance
cobblestone like appearance
zenkers diverticula
out pouching of the esophageal wall, in particular the pharynx and upper esophagus
traction diverticula
out pouching of the esophageal wall, in particular all mucosal layers
esophageal varices
dilated veins of the distal esophagus most commonly a result of portal hypertension
appearance of esophageal varices
rosary bead appearance
hiatal hernia
herniation of a portion of the stomach through the esophageal hiatus and into the thoracic cavity
hiatal hernia appearance
schatzkis ring
achalasia
uncoordinated peristalsis due to neurologic failure. functional obstruction of the distal esophagus due to unrelaxed sphincter
achalasia appearance
bird beak appearance
mallory-weiss syndrome
perforation of the esophagus caused by forceful vomitting often seen in patients with bulimia. A tear in the mucous layer at the junction of the esophagus and stomach
peptic ulcer disease (PUD)
inflammatory process of the stomach and duodenum often caused by a bacterial infection (h pylori)
PUD appearance
duodenal/gastric craters and/or radiating folds
helicobacter pylori (h pylori)
bacteria that causes infection in the stomach with symptoms of bloating, belching, naseau, vommitting, abdominal pain and fatigue
crohns disease/regional enteritis
chronic inflammatory disorder of idiopathic origin with granulomatous lesions which may lead to obstructions, most commonly seen in the ileum
appearance of crohns disease/regional enteritis
irregular thickening/distortion of bowel mucosa
small bowel obstruction (SBO)
obstruction of small bowel caused by post operative adhesions, hernias, luminal occlusions, inflammation
SBO appearance
distended bowel loops with gas and air, best seen upright or decub.
adynamic ileus
disorder involving intestinal motor activity where flui/gas do not progress normally; often seen post operative
intussusception
telescoping of the bowel into itself (proximal into distal) resulting in obstruction; more common in children than adults
appearance of intussusception
coiled spring on X-ray or concentric circle on CT
volvulus
distended cecum or rectum
appearance of volvulus
bird beak appearance
ulcerative colitis
inflammation of the colon appearing in young adults idiopathically
appearance of ulcerative colitis
loss of austral markings in the descending colon and sigmoid
colon cancer
polypoid and annular lesions in the colon
appearance of colon cancer
applecore appearance
hirschsprungs disease
lack/loss of nerves to distal colon, loss of muscle tone, dilated distal colon, congenital, infants
hirschsprungs disease appearance
in infants a collapsed colon and dilated distal colon
toxic megacolon
lack/loss of nerves to distal colon, loss of muscle tone, can vein children and adults, often resulting in toxicity
appearance of toxic megacolon
tubular appearance of the colon
fistula
abnormal connection between and organ, vessekm or intestine and another structure; usually caused by surgery but also from infection/inflammation
congenital tracheoesophageal fistula
incomplete separation of the esophagus and trachea during fetal development
acquired tracheoesophageal fistula
due to malignancy of the mediastinum, trauma, or infection
GERD
gastroesophageal reflux disease; inflammation of the esophagus
barretts esophagitis
the normal esophageal lining is destroyed
cancer of the esophagus
more common in men than women; strong correlation to smoking and excessive alcohol consumption
esophageal diverticula
out pouching of the esophageal wall
epiphrenic esophageal diverticula
occurs in the distal esophagus characterized with uncoordinated peristalsis and sphincter action
hiatal hernia is most commonly characterized by
schatzkis ring
schatzkis ring
cardiac sphincter is seen above the diaphragm
perforation of the esophagus can be a complication of or caused by
esophagitis, peptic ulcer disease, neoplasm, external trauma, foreign body, instrumentation, forceful vommitting
gastritis
inflammation of the stomach which can be caused by irritation (alcohol, corrosive agents), infection and can be characterized by thickened mucosa and rugea
cancer of the stomach usually has a poor prognosis
sue to pain usually occurring late in the disease process with a 10% survival rate
cancer of the stomach is demonstrated radiographically by
mass, stricture, thickened mucosa
appendicitis develops when
the neck of the appendix becomes blocked, material trapped becomes infected, infection causes distention, best seen on CT; NOT BARIUM ENEMA!
diverticulosis/diverticulitis
outpouchings of the bowel wall, rare in persons under age 30, common in persons over age 60, most commonly seen in the sigmoid
crohns colitis
identical to crowns of the small bowel, best seen on an air contrast barium enema as tiny isolated , discrete erosions of the mucosa
cancer of the colon
more common in men than women with peak incidence of 50-70 y/o; seen as polypoid lesions/”apple core”
volvulus of the colon
the twisting of the bowel upon itself which may lead to obstruction most commonly seen in cecum/sigmoid
cathartic colon
loss of motility in colon due to overuse of laxatives, muscles of colon “quit”, seen radiographically as a loss of austral folds
metabolism
the conversion of nutrients into fuel
the alimentary canal aka
digestive trac, a musculomembranous tube that extends continuously from the mouth to anus (approx. 30 ft)
walls of the digestive tract
mucosa/mucous membrane
submucosa
muscularis
serosa
lumen
inner/hollow space of the digestive tract
mucosa/mucous membrane
innermost layer of the digestive tract containing the epithelial layer; barrier between body and gi tract
epithelial layer
semi permeable membrane
submucosa
second layer of the digestive tract just below the mucosa containing glands, blood vessels, nerve and lymph
muscularis
muscular layer of the digestive tract containing two layers of muscles running circular and longitudinal whose function is peristalsis
serosa
the outermost layer of the digestive tract that is anchored to the abdominal wall by mesentery
the accessory organs incluse
salivary glands, pancreas, liver, and gall bladder
function of salivary glands
produce saliva
function of the pancreas
produces digestive enzymes and alkaline solution
function of the liver
produces bile
function of the gall bladder
stores, concentrates, expels bile, responds to cholecystokinin
function of the mouth
chewing, beginning of digestion
function of the pharynx
pass bolus
function of the esophagus
pass bolus
function of the stomach
digestion
function of the small intestine
digestion and absorption
function of the large intestine
absorption of water and the formation and elimination of stool
mastication
the act of hewing
buccal
referring to the mouth
bolus
ball of chewed food matter
deglutition
the act of swallowing
salivary glands
parotid
submandibular
sublingual
parotid glands
largest most superior located by mandibular ramus containing stetsons/parotid; empties along cheek
submandibular glands
located inside the mandibular angle containing whartons; empties onto floor - frenulum
sublingual glands
located under the tongue containing rivinus, many small ducts along floor of mouth
stomach
expandable muscular sac between esophagi and small intestine whose function is physical and chemical action of digestion
stomach is divided ito 4 parts
cardia
fundus
body
pylorus
cardia
portion of stomach immediately surrounding the esophageal opening
fundus
superior portion on the stomach, dome shaped upper the diaphragm
body
middle, main portion of the stomach between the fundus and pylorus
pylorus
distal portion of the stomach which narrows into pyloric antrum
lesser curvature
the right border of the stomach with a concave curve
greater curvature
the left border of the stomach, 4-5x longer than the lesser; convex curvature
gastric ruggae
thick inner mucosal lining of the body of the stomach with numerous folds whose mechanical actions bless and churns chyme
openings between the esophagus and stomach
esophagogatric junction
gastro-esophageal junction
cardiac orifice
cardiac valve or sphincter (1 way)
openings between the stomach and small intestine
pyloric orifice
pyloric valve/sphincter (1 way)
the small intestine
extends from pyloric sphincter of stomach to the opening of the large intestine called the ileocecal valve
the small intestine is divided into three distinct portions
duodenum (proximal)
jéjunum (middle)
ileum (distal)
the inner mucosa layer of the small intestine contains a series of finger like projections called
villi
villi are
membranes that allow nutrients to be absorbed and have even smaller projections called microvilli
duodenum
c-shaped, 8-10” long, widest/shortest portion of the small bowel, first portion called duodenal bulb; biliary system enters small intestine in bulb
the romance of the abdomen
head of pancreas adjacent to the c-loop of the duodenum
jejunum
second largest portion of the small bowel, has a coiled spring and feathery appearance when filled with barium
ileum
longest and most distal portion of small bowel but smallest in diameter, terminates at ileocecal valve
large intestine
approx 5-6’ begining at junction of small intestine and ending at anus.
main function of the large intestine
absorption of water and elimination of waste product
large intestine includes
ileocecal valve cecum vermiform appendix ascending colon right colic (hepatic) flexure transverse colon left colic (splenic) flexure descending colon sigmoid portion rectum anal canal
ileocecal valve
opening between small and large intestine
cecum
pouch like portion below the junction of the ileum and colon
vermiform appendix
narrow worm like tube attached to the posteromedial side of the cecum
ascending colon
passes superior from the junction of the colon
right colic (hepatic) flexure
sharp angle at ascending and transverse
transverse colon
has greatest amount of potential movement
left colic (splenic) flexure
sharp angle at junction of transverse/descending
descending colon
passes inferiorly
sigmoid portion
forms s shaped loop and ends at rectum at level of third sacral segment
rectum
extends from sigmoid to anal canal
anal canal
terminated at the anus
haustra
series of pouches along the large intestine
taeniae coli
muscular bands that form the pouches known as haustra
peristalsis
rhythmic, muscular waves of contraction by which the alimentary canal moves its contents toward the rectum
chole
bile
cysto
sac/bladder
cholani
bile ducts
cholecyst
gallbladder
choledoch
common bile duct
cholecystogram
radiographic exam of gallbladder
cholangiogram
radiographic exam of biliary ducts
cholelithiasis
presence of gallstones
cholecystectomy
surgical removal of the gallbladder
t-tube cholangiogram
radiographic exam of biliary ducts via a surgically placed removable tubing
liver
largest gland in bodying RUQ, produces bile
the liver produces
bile
peritoneum
double walled serous membrane that lines the abdimino-pelvic cavity with three portions - parietal, visceral, and peritoneal
the lining of the abdominal wall is
perietal peritoneum
the lining of the intestines
visceral peritoneum
the spaces between layers
peritoneal cavity
folds of the peritoneum surround and support the abdominal organs with
omentum
mesentery
omentum contains
greater and lesser - peritoneal folds fat like aprons that insulate
greater omentum
greater curvature of the stomach to the transverse colon
lesser omentum
lesser curvature of the stomach to the duodenum
mesentery
peritoneal folds connect bowel loops together and to abdominal wall
blood vessels, nerve and lymph are used
for portal circulation from intestines to liver - mesenteric vein
bile is produced by the
LIVER - not the gallbladder
blood is conveyed to the liver through the
portal vein and hepatic artery
the two main hepatic ducts join to form the
common hepatic ducts
the common hepatic duct and the cystic duct join together to form
the common bile duct
the common bile duct and the and the pancreatic duct join together and enter into a chamber called the
hepatopancreatic ampulla aka the ampula of vater
the hepatopancreatic ampula opens into the descending portion of the duodenum and is controlled by a circular muscle called the
sphincter of oddi
the distal end of the common bile duct is controlled by the
choledochal sphincter as it enters the duodenum
