Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
100 Cards in this Set
- Front
- Back
|
What additional smooth muscle layer does the stomach have?
|
Innermost oblique layer. Allows for churning
|
|
|
Where are the exocrine secretions of the pancreas and liver released?
|
duodenum
|
|
|
Is there an adventitia anywhere in small intestine?
|
Yes, in the part of the duodenum that is retroperitoneal
|
|
|
What are villi composed of?
|
Core of lamina propria covered by epithelium. Increase surface area 10X.
|
|
|
The presence of ______ are diagnostic for small intestine
|
Villi
|
|
|
What are permanent folds, involving mucosa and submucosa, that increase surface area 2-3 times in the small intestines?
|
Plica circulares
|
|
|
What is composed of two serosal layers and an intervening layer of loose CT that serves to suspend (most of) small intestine from body wall?
|
mesentery
|
|
|
What are the layers of the small intestine?
|
1) Mucosa
2) Submucosa (forms the core of the plicae) 3) Muscularis externa 4) Serosa |
|
|
What type of epithelium is in the small intestine mucosa? What are some cells in it?
|
Simple columnar. It's highly adapted for absorption. Contains goblet cells (secrete mucus) and microvilli (increase surface area 20x)
|
|
|
What are the absorptive cells of the Small Intestine?
|
Enterocytes
|
|
|
What are lacteals?
|
Blind-ended lymphatic channels in lamina propria core of villi
|
|
|
What are the four cell types forming intestinal glands?
|
Goblet cells, absorptive cells, Paneth cells, and enteroendocrine cells
|
|
|
Which direction do secretory granules of enteroendocrine cells face and why?
|
Face towards lamina propria (toward capillaries) because they secrete into blood stream, NOT into lumen
|
|
|
What type of cells are enterocytes?
|
Epithelium - simple columnar
|
|
|
What is the glycocalyx?
|
"Sugar coating" that lines the EC surface, sequesters enzymes impt in digestion and in transport of nutrients
|
|
|
What type of glands are intestinal glands? Where are they located?
|
Simple tubular, formed by invagination of epithelium into lamina propria. They lie between the villi.
|
|
|
Where are the intestinal lymphatics located ? (what layer)
|
Lamina propria
|
|
|
What are groups of nodular aggregates of lymphatics called?
|
Peyer's patches
|
|
|
Where are Brunner's glands?
|
Duodenum submucosa ONLY
|
|
|
What are lipids absorbed thru?
|
Lacteals. Emulsified with bile.
|
|
|
What do Paneth cells produce? What's their function?
|
Produce lysozyme, an enzyme with antibacterial activity. Thought to be involved in killing bacteria in food.
|
|
|
How can the duodenum be differentiated from the rest of the small intestine?
|
Presence of <b>Brunner's glands in submucosa</b>
|
|
|
What do Brunner's glands produce?
|
An alkaline mucus that neutralizes the acidic chyme coming out of stomach
|
|
|
In what part of GI tract are goblet cells most numerous?
|
As you move distally they become more numerous (they never become the dominant cell type, though)
|
|
|
Dark red granules in the bases of intestinal glands are characteristic of what type of cell?
|
Paneth
|
|
|
Between what layers is Auerbach's plexus located?
|
Between inner (circular) and outer (longitudinal) layers of muscularis externa
|
|
|
What is MALT?
|
mucous associated lymphoid tissue
|
|
|
What structure MOST increases the surface area of small intestine?
|
microvilli
|
|
|
What triggers secretion of secretin?
|
The acidity of chyme
|
|
|
What does secretin do?
|
Stimulates secretion of bicarbonate by centroacinar cells of pancreas
|
|
|
What triggers secretion of cholecystokinin (CCK?)
|
Fatty acids and L-amino acids in the duodenum
|
|
|
What does CCK do?
|
stimulates release of secretory granules by pancreatic acinar cells. Also stimulates contraction of smooth muscles of gall bladder wall
|
|
|
Are there any plicae or villi in the large intestine?
|
No
|
|
|
What are the functions of the large intestine?
|
Water absorption; Vitamin absorption
|
|
|
What are diagnostic features of the large intestine?
|
1) Lack of villi
2) Parallel arrangement of intestinal glands |
|
|
What is the name for the outer longitudinal portion of the muscularis externa in large intestine, divided into three separate bands?
|
Taeniae coli
|
|
|
What type of epithelium is mucosa of large intestine?
|
Simple columnar. Contains absorptive and goblet cells.
|
|
|
What type of glands are the intestinal glands of colon?
|
Simple tubular
|
|
|
What type of glands are the intestinal glands of <b>appendix</b>?
|
Simple tubular
|
|
|
What are distinguishing features of appendix?
|
1) Muscularis externa similar to small intestine - no taeniae coli and complete outer longitudinal layer
2) prominent lymphoid tissue 3) Mucosa resembles that of the colon - straight intestinal glands and no villi |
|
|
How does the rectum change at the recto-anal border change?
|
Goes from a simple columnar epithelium to stratified squamous moist (anal canal)
Inner circular layer of muscularis externa becomes internal anal sphincter. External anal sphincter is skeletal muscle. |
|
|
Where is the only place in GI system that apocrine glands are located?
|
ANUS!
|
|
|
What are the anal columns of Morgagni?
|
number of vertical folds, produced by an infolding of the mucous membrane and some of the muscular tissue in the upper half of the lumen of the anal canal. 5-10 longitudinal columns
|
|
|
What is another term for the junction of the rectum and anal canal?
|
Pectinate line
|
|
|
What type of glands are apocrine sweat glands?
|
Simple coiled tubular glands
|
|
|
What is the name of endocrine component of pancreas?
|
Islets of Langerhans
|
|
|
What type of gland is the exocrine portion of the pancreas?
|
Compound acinar
|
|
|
What hormones are the exocrine portions of pancreas dependent on?
|
Secrtin and CCK (enteroendocrine cell secretions)
|
|
|
What are the three types of cells in islets of Langerhans?
|
Beta, Alpha, Delta
|
|
|
What is a centroacinar cell?
|
Cell in the middle of the acinus that form the beginning of intralobular ducts
|
|
|
What do beta cells secrete?
|
Insulin
|
|
|
What do alpha cells secrete?
|
Glucagon
|
|
|
What do delta cells secrete?
|
Somatostatin
|
|
|
What do acinar cells of exocrine pancreas secrete?
|
Inactive forms of digestive enzymes which get activated in duodenum.
|
|
|
The pancreas is unique in that duct system begins with ______________ cells within the acinus.
|
centroacinar
|
|
|
Zymogen granules: Defn
|
Secretory granules that contain enzymes
|
|
|
How do the Islets of Langerhans differ in appearance from the acini?
|
They appear as lighter clusters. (spherical clusters of cells and fenestrated capillaries)
|
|
|
What type of capillaries are the Islets of Langerhans supplied by?
|
Because they're endocrine cells, they're supplied by <b>fenestrated</b> capillaries.
|
|
|
What do the centroacinar cells produce?
|
The bicarbonate-rich component of exocrine pancreas
|
|
|
What is the ampulla of Vater?
|
The papilla where the main pancreatic duct opens into the duodenum.
|
|
|
What are the two main pancreatic ducts that empty into the duodenum?
|
1) Main duct (of Wirsung)
2) Accessory duct (of Santorini) |
|
|
What are the secretory canaliculi?
|
The first part of duct system at center of acini, where granules are released into
|
|
|
What are the intercalated ducts lined with?
|
Simple cuboidal and low columnar epithelium
|
|
|
What are the interlobular ducts lined with?
|
Simple or stratified columnar epithelium
|
|
|
What are the excretory ducts lined with?
|
Stratified columnar
|
|
|
What is the largest gland in body?
|
Liver.
|
|
|
What is the endocrine function of liver?
|
Synthesizes and Releases osmotic-controlling proteins in blood (eg albumin)
|
|
|
What are the two main vessels thru which the liver receives blood?
|
1) Portal vein
2) Hepatic artery |
|
|
What is the exocrine function of liver?
|
Makes bile
|
|
|
What is the basic structural unit of liver?
|
The classical lobule
|
|
|
what is the classical lobule outlined by?
|
Interlobular CT
|
|
|
What is Glisson's capsule?
|
The covering of the liver that protects it and makes it hard(ish) to lacerate. Spleen is much more easily lacerated.
|
|
|
What is the path of blood thru the basic lobule?
|
Comes in from terminal branches of portal vein and hepatic artery and flows thru sinusoids to central vein.
|
|
|
What separates the anastomosing rows of dark red hepatocytes?
|
Sinusoids
|
|
|
What is the portal triad?
|
Branches of hepatic portal vein, hepatic artery, bile duct
|
|
|
What contains the portal triad?
|
Portal canals
|
|
|
What are the three definitions of lobulation patterns?
|
1) Classical hepatic lobule - hexagon with portal canals at each corner
2) Portal lobule - triangle with central vein at each corner and portal canal in center 3) Liver acinus - diamond shaped - takes into account blood and bile flow |
|
|
Which lobulation pattern is based on blood flow?
|
Classical hepatic lobule - hexagon with portal canals at each corner.
Endocrine secretions of hepatocytes carried away in sinusoids towards central vein |
|
|
Which lobulation pattern is based on bile flow?
|
Portal lobule - triangle with central vein at each corner and portal canal in center. Drains toward bile duct located (as in other exocrine glands) with vascular supply in center of lobule.
|
|
|
Which lobulation pattern is based on bile and blood flow?
|
Liver acinus - diamond shaped
|
|
|
What % of blood to liver is brought by hepatic artery? portal vein?
|
30%; 70%
|
|
|
What type of epithelium is bile duct?
|
Simple cuboidal
|
|
|
What do the liver lymphatic channels do?
|
Drain lymph made by hepatocytes (lymph contains a large concentration of what will eventually be plasma proteins) - drains to <b> thoracic duct</b>
|
|
|
Bile flow is toward the ___________ (center or periphery) of liver lobule.
|
Periphery
|
|
|
A _________ is located in the center of the classical lobule.
|
Central vein
|
|
|
What is the space of Dissi?
|
Between free surface of hepatocytes and sinusoidal lining cells. Contains blood plasma and microvilli of hepatocytes, area of metabolite exchange
|
|
|
What are Kuppfer cells?
|
specialized macrophages located in the liver lining the walls of the sinusoids; Phagocytose aging RBCs and other debris
|
|
|
What is the bile canaliculus?
|
Tiny tunnels that exist between hepatocytes that drain to bile duct
|
|
|
What's unique about hepatocyte nuclei?
|
They're so active many are binucleate and most are polyploid
|
|
|
What is the <b>zone of permanent function</b>?
|
In hepatic sinuisoid, most metabolically active and least susceptible to damage.
|
|
|
What is the <b>zone of varying activity</b>?
|
Variable metabolic activity in hepatic sinuisoid
|
|
|
What is the <b>zone of permanent repose</b>?
|
Least metabolically active and most susceptible to damage.
"Canary in coal mine." Used to scan for disease; they're the first cells to die in disease (aka Tylenol poisoning) |
|
|
What are the Canals of Herring?
|
Lie in septae between adjacent classical hepatic lobules, finest branch of bile duct
|
|
|
What is the function of the gall bladder?
|
Stores and concentrates bile made in liver
|
|
|
What are pseudodiverticulae?
|
in gallbladder, they resemble glands due to convoluted architecture.
|
|
|
What's the epithelium of gallbladder?
|
Simple columnar with brush border
|
|
|
What area of Simple columnar cells of gallbladder epithelium have highest [organelles?]
|
Apical area. This is because they're involved in active transport of Na+ from lumen to intercellular space, causing water to follow, thus concentrating the bile.
|
|
|
What histological feature is characteristic of gallbladder?
|
The numerous infoldings
|
|
|
What layer is lacking in gallbladder?
|
Muscularis mucosa
|
|
|
What stimulates the contraction of the muscularis in gall bladder, an irregular network of smooth muscle fibers?
|
CCK
|
