Term
liver, pancreas, intestinal glands
they are embryological outgrowths of the GI tract |
|
Definition
| list some of the glands of the GI tract and their embryological role in relation to the GI tract. |
|
|
Term
|
Definition
| name the diffuse lymphoid tissue scattered throughout the GI tract |
|
|
Term
1)mucosa
2)submucosa
3)muscularis externa
4)adventitia (serosa) |
|
Definition
| list the 4 layers of the GI tract |
|
|
Term
1)epithelium
2)lamina propria
3)muscularis mucosa
(ELM) |
|
Definition
| list the 3 layers of the mucosa |
|
|
Term
|
Definition
which layer of the gut is being described?
different modifications at different levels of the GI tract
secretory and absorbtive function |
|
|
Term
|
Definition
which layer of the gut is being described?
underlying connective tissue (below epithelium) contains lymphatic nodules, glands, and vessels |
|
|
Term
muscularis mucosa
(note: without the musc. mucosa, the lamina propria and submucosa would be continuous -they are basically the same thing) |
|
Definition
which layer of the gut is being described?
thin layer of smooth muscle, boundary between mucosa and submucosa |
|
|
Term
absorbtion, barrier, and secretion
(ABS) |
|
Definition
| list the 3 functions of mucosa |
|
|
Term
|
Definition
which layer of the gut is being described?
loose to dense irregular connective tissue layer. supports mucosa, contains larger blood vessels, nerves, lymphatics |
|
|
Term
| muscularis externa (propria) |
|
Definition
which layer of the gut is being described?
usually inner circular and outer longitudinal smooth muscle layers. Muscle fibers oriented at right angles to each other. |
|
|
Term
| segmentation, peristalsis |
|
Definition
|
|
Term
|
Definition
| local contractions that allow mixing of food. occur both proximally and distally in either direction |
|
|
Term
|
Definition
| propels food DISTALLY ONLY (aborally), and has less frequent contractions than the other type of gut movement |
|
|
Term
|
Definition
| outer loose connective tissue layer of the gut. Contains major nerves, vessels, and adipose tissue |
|
|
Term
| serosa or visceral peritoneum |
|
Definition
| what is the adventitia referred to within the abdominal cavity |
|
|
Term
| simple squamous (mesothelium) |
|
Definition
| what kind of epithelium lines the adventitia of the gut? |
|
|
Term
| supporting mesentery, and in some areas it merges with retroperitoneal tissue (like the esophagus and rectum) |
|
Definition
| what is the visceral peritoneum of the gut continuous with? |
|
|
Term
| ganglia are located within the wall of the gut, within submucosa and muscularis externa |
|
Definition
| parasympathetic nerves synapse with ganglia located near the effector organ, where is this in the GI tract? |
|
|
Term
Meissner's plexus
parasympathetic |
|
Definition
| which clusters of autonomic ganglia are located within the submucosa? sympathetic or parasymathetic? |
|
|
Term
myenteric plexi aka Aurbach's(remember mye = muscle)
parasympathetic |
|
Definition
| which clusters of autonomic ganglia are located between the inner circular and outer longitudinal muscle layers? sympathetic or parasymathetic? |
|
|
Term
| secretion, absorbtion, and contraction of the muscularis mucosa (functions of the mucosa) |
|
Definition
| what do Meissner's plexi control? |
|
|
Term
| muscle movement in the muscularis externa |
|
Definition
| what do Aurbach's plexi control? |
|
|
Term
|
Definition
| short muscular tube lined with stratified squamous non-keratinized epithelium |
|
|
Term
upper 1/3 is voluntary skeletal muscle
middle 1/3 is mixed smooth and skeletal
lower 1/3 is smooth muscle only |
|
Definition
| which parts of the esophagus are skeletal muscle, and which are smooth muscle? |
|
|
Term
|
Definition
| what is different about the epithelium of the esophagus in birds and cows compared to humans? |
|
|
Term
| the esophageal sphincter (and muscle leading to it) are involuntary smooth muscle |
|
Definition
| what explains why vomiting is (mostly) involuntary? |
|
|
Term
|
Definition
| what is contained in the gastro-esophageal junction? |
|
|
Term
| Doves -All other birds have smooth muscle in their esophagi which means they have to tilt their head back to let gravity allow them to drink |
|
Definition
what are the only birds that can swallow due to the presence of skeletal muscle in their esophagus?
Hint: they regurgitate pigeon milk |
|
|
Term
| heart burn, due to regurgitation of stomach acid into distal esophagus from cardia of stomach |
|
Definition
| what is pyrosis? what causes it? |
|
|
Term
|
Definition
| distensible organ used for food storage |
|
|
Term
mechanical: muscular activity
chemical: gastric secretions known as chyme |
|
Definition
| in the stomach, food undergoes mechanical breakdown from ___ and chemical break down from ____ |
|
|
Term
| means 1 stomach chamber, and it is the case with most animals |
|
Definition
| what does monogastric mean, and is this common? |
|
|
Term
| the stomach has a third inner oblique layer in the muscularis externa (about a 45 degree angle to the other layers) |
|
Definition
| what is special about the stomach musculature? name it! |
|
|
Term
| LITTLE, exceptions: water, alcohol, and some drugs like aspirin |
|
Definition
| what is absorbed in the stomach? |
|
|
Term
|
Definition
| what are the names of the prominent longitudinal folds of the stomach? |
|
|
Term
| cardia, fundus, body, pylorus |
|
Definition
| name the regions of the stomach north to south |
|
|
Term
|
Definition
| part of the stomach that is surrounded by the smooth muscle cardiac sphincter |
|
|
Term
| predominantly mucus secreting glands |
|
Definition
| what type of glands are found in the cardia? |
|
|
Term
|
Definition
| glandular portion of the stomach |
|
|
Term
| acid, pepsin and SOME mucus |
|
Definition
| what does the glandular portion of the stomach secrete? |
|
|
Term
| primarily mucus, and gastrin secreting glands |
|
Definition
| what type of glands are in the pylorus? |
|
|
Term
| smooth musc. pyloric sphincter |
|
Definition
| controls outflow from stomach into duodenum |
|
|
Term
|
Definition
| loss of stomach epithelium/mucosa (in stomach or duodenum) |
|
|
Term
ulcer
bleeding because of the blood vessels in the lamina propria |
|
Definition
| damage to stomach lining extending below the basement membrane to cause bleeding |
|
|
Term
|
Definition
| partial loss of epithelium in the stomach with no bleeding |
|
|
Term
antacids: tagamet, cimetidine
and long-term antibiotics |
|
Definition
| what do you treat ulcers with? |
|
|
Term
|
Definition
| chronic bacterial infection associated with 75% of stomach ulcers |
|
|
Term
the line between the glandular and non-glandular portions of the stomach of a rat or horse.
IF humans had this, it would be between the cardia and fundus (possibly between fundus and pylorus too) |
|
Definition
| what is a margo plicadis? where would you find this in a human being? |
|
|
Term
| foveolae are gastric pits (that form the entrance to gastric glands) found in the glandular body of the stomach |
|
Definition
| what are foveolae and where are they found? |
|
|
Term
|
Definition
| what kind of glands are gastric glands |
|
|
Term
foveolae = gastric pits
they secrete: 2 L of gastric juice/day consisting of
1) HCl
2) pepsinogen
3) gastrin
4) renin
5) lipase |
|
Definition
| what do foveolae secrete? |
|
|
Term
| HCl cleaves pepsinogen to pepsin and pepsin breaks down proteins |
|
Definition
| what converts pepsinogen to pepsin, and what does pepsin do? |
|
|
Term
1)mucus secreting cells
2) acid secreting cells
3) pepsin secreting cells
4) enteroendocrine cells
5) stem cells |
|
Definition
| what are the 5 classes of cells that gastric glands contain? |
|
|
Term
found on luminal surface and upper 1/3 of the pit
renewed every 3-5/4-7 days |
|
Definition
| how often are mucus cells renewed and where are they found in the foveolae? |
|
|
Term
surface mucus cells-secrete thick INSOLUBLE mucus + bicarb ions, located on the surface
mucus neck cells-secrete SOLUBLE mucus, located in the upper 1/3 of the gastric pit at the "neck" of the gastric gland
SINS (Surface Insouble, Neck Soluble) |
|
Definition
| what is the difference between surface mucus cells and mucus neck cells? |
|
|
Term
| parietal aka oxyntic cells |
|
Definition
|
|
Term
| parietal/oxyntic cells- they secrete intrinsic factor which is needed for b12 absorption from the ileum |
|
Definition
| which stomach secretory cells are essential to B12 absorbtion? |
|
|
Term
|
Definition
| where in a gastric gland are acid secreting cells most numerous? |
|
|
Term
bottom 1/3 of gastric glands
chief cells, peptic cells, zymogenic cells |
|
Definition
| where are pepsin secreting cells found? what are other names for these cells? |
|
|
Term
mucus: look clear
parietal: pink to purple
chief: purple due to LOTS of ribosomes |
|
Definition
| describe how the cells in a gastric gland will stain |
|
|
Term
|
Definition
| how long do parietal and chief cells live? |
|
|
Term
| ANS + hormones from endocrine cells in the pylorus |
|
Definition
| what controls parietal and chief cell activity? |
|
|
Term
amine precursor uptake and decarboxylation
they are paracrine cells that secrete a variety of peptide hormones in response to local factors. They control GI motility and gastric secretion. |
|
Definition
| describe the function of APUD(enteroendocrine) cells |
|
|
Term
|
Definition
| stimulates secretion of HCl and pepsin or secretin (secreted by S cells) |
|
|
Term
|
Definition
| inhibits gastric secretions and stimulates smooth muscle contraction |
|
|
Term
|
Definition
| where are stem cells found in gastric glands? |
|
|
Term
they divide and replace lost or damaged epithelial cells and as they mature they migrate up OR down the gland
in the small intestine the stem cells migrate UP the villus, mature, and shed |
|
Definition
| what is the function of stem cells in the stomach and where do they move? how is this different from stem cells in the small intestine? |
|
|
Term
4-6 meters
d: 25cm/1ft
j: 2m
i: 3m |
|
Definition
how long is the small intestine?
duodenum?
jejunum?
ileum? |
|
|
Term
|
Definition
| where in the GI tract is the primary site of absorbtion and digestion? |
|
|
Term
plica circulares or Valves of Kerkring
note: they are not functioning open/close valves, they just contact each other from either side of the intestine tube like valves do |
|
Definition
| mucosa & submucosa arranged into valve-like folds/rings throughout the small intestine called ______ |
|
|
Term
plica circulares have a submucosal core
villi have a lamina propria core |
|
Definition
| compare the core of a plica circulares to a villi |
|
|
Term
|
Definition
| what is the space between villi called? |
|
|
Term
| capillaries & lymphatics for absorbtion of nutrients |
|
Definition
| what is found within the lamina propria? |
|
|
Term
| simple columnar epithelium |
|
Definition
| what kind of "-thelia" is found on villi? |
|
|
Term
simple columnar epithelium
enterocytes |
|
Definition
| what kind of "-thelia" is found on villi? what kind of cells are these? |
|
|
Term
| microvilli - striated or brush border |
|
Definition
| highly folded, modified, apical surface of villi in the small intestine |
|
|
Term
| glycocalyx of disaccharides, this is the site of membrane digestion |
|
Definition
| what coats the surface of microvilli? what is this the site of? |
|
|
Term
| mucinogen which becomes mucus, secreted by goblet cells |
|
Definition
| stored in membrane bound granules; lubricates and protects epithelium of the GI tract. what secretes this? |
|
|
Term
| at the base of the crypts of leiberkuhn |
|
Definition
| where are stem cells and Paneth cells found in the small intestine? |
|
|
Term
|
Definition
| how often is the epithelial lining in the small intestine replaced? |
|
|
Term
|
Definition
| this makes up 30% of feces |
|
|
Term
|
Definition
| cells that contain large eosinophillic granules called defensins and enzymes, including lysozyme |
|
|
Term
1)S cells: secretin, stimulates release of bicarbonate from the pancreas
2)I cells: CCK(cholycystekinen) stimulates pancreatic secretion and contraction of gallbladder
3)A cells: glucagon, increases blood sugar
4)also there are cells that make G1P that don't have a name |
|
Definition
| list the secretory products of the 3(4) APUD cells and what their secretions stimulate |
|
|
Term
| lamina propria & submucosa |
|
Definition
| in what gut layer would you find MALT? |
|
|
Term
|
Definition
| contains plasma cells and secretes IgA (in the small intestine) |
|
|
Term
| microfold cells - squamoid enterocytes modified for antigen sampling and uptake of macromolecules |
|
Definition
| what are M cells and where are they found? |
|
|
Term
|
Definition
| dome shaped grossly visible patches of MALT that can project into the lumen, located mainly in the ileum, but can be seen throughout the small intestine |
|
|
Term
|
Definition
| where are Brunner's glands found (in what part of the gut and what layer?) |
|
|
Term
|
Definition
| large numbers of highly convoluted branched tubuloalveolar submucosal glands that secrete mucus and zymogens unique to the duodenum |
|
|
Term
neutralize gastric acid and pepsin
this is assisted by the pancreas and gallbladder |
|
Definition
| what is the main function of the duodenum? |
|
|
Term
|
Definition
| name of the part of the duodenum that the pancreatic duct and bile duct empty at |
|
|
Term
chyme from the stomach hitting the duodenum
secretin and CCK promote secretion of the exocrine pancreas |
|
Definition
| stinulates the release of 2 hormones from APUD cells: secretin and CCK |
|
|
Term
| highly alkaline due to bicarbonate ions to neutralize stomach acid |
|
Definition
| what pH are pancreatic secretions? |
|
|
Term
|
Definition
| promotes secretion of exocrine pancreas, stimulates contraction of gallbladder and & release of bile acids |
|
|
Term
|
Definition
| act as emulsifying agents for digestion of lipids by forming micelles |
|
|
Term
secreted as inactive precursors(zymogens) trypsinogen and chymotrypsinogen in the pancreas
-they help digest proteins (also amylase and lipase) |
|
Definition
| what do trypsin and chymotripsin do (in general) and where are they secreted? |
|
|
Term
| luminal digestion and membrane digestion |
|
Definition
| what are the two componenets of digestion? |
|
|
Term
|
Definition
| involves mixing of chyme with pancreatic enzymes leading to molecular breakdown |
|
|
Term
|
Definition
| digestion that involves enzymes of the glycocalyx on plasma membrane of enterocytes |
|
|
Term
| peptidases, peptide hydrolases, disaccharidases |
|
Definition
| what enzymes do enterocytes synthesize? |
|
|
Term
| absorbtion of carbs and amino acids |
|
Definition
| what are carrier proteins produced by enterocytes used for? |
|
|
Term
1) denatured by HCl from parietal cells, then hydrolyzed by pepsin into fragments
2) pancratic enzymes: trypsin, chymotrypsin, elastase, and carboxypepsidase -> formation of small polypsptide fragments.
3) amino acids are absorbed by enterocytes via active transport by peptide hydrolases (this is done my membrane digestion with the glycocalyx)
4) go to the liver |
|
Definition
| describe protein digestion |
|
|
Term
1) salivary & pancreatic amylase hydrolyzes starch to disaccharides (sucose and maltose)
2) disaccharides -> monosaccharides (glucose, galactose, fructose) and then they are absorbed by facilitated diffusion
3) BOTH amino acids and monsaccharides are absorbed by enterocytes lining the villi, transported across epithelium, enter capillaries within the lamina propria which go through the portal vein to the liver for storage |
|
Definition
| describe carbohydrate digestion & absorbtion (primary starches, poly-, oligo-, and di- saccharides) |
|
|
Term
| 1) primary triglycerides from the diet emulsified by action of bile acids 2) further broken down into monglycerides & FA's by pancreatic lipse forming extracellular micelles 3) micells are absorbed by enterocyes, re-synthetized into triglycerides within the enterocytes & coated with proteins and phospholipids to form inTRAcellular chylomicrons 4) chylomicrons are trasported across the mucosa to lacteals, then carried to the thoracic duct & general circulation |
|
Definition
| describe lipid digestion & absorbtion |
|
|
Term
| blind-ended lymph vessels within the lamina propria of villi where chylomicrons go |
|
Definition
|
|
Term
| they would gum up the blood vessels |
|
Definition
| why don't lipids go directly into the blood stream? |
|
|
Term
| cecum, appendix, acending, transverse, descending, and sigmoid colon & rectum |
|
Definition
| what (organs)are included in the "large intestine"? |
|
|
Term
| no, it is not used for absorbtion as much |
|
Definition
| does the large intesting have villi or plica circulares? why? |
|
|
Term
|
Definition
small blind-ended sac, 2-13 cm in length distal to ileo-ceal junction
vestigeal cecum |
|
|
Term
|
Definition
| what is used for bacterial digestion of herbivores and contains a large amount of submucosal MALT that is very active in children? |
|
|
Term
H20 absorbtion and electrolyte resorbtion
also produces mucus for elimination of undigested food and waste |
|
Definition
| what is the primary function of the colon? other functions? |
|
|
Term
| goblet cells in epithelium, colonic glands in submucosa |
|
Definition
| in which gut layer are goblet cells and colonic glands found in the colon? |
|
|
Term
| its like the small intestine except Paneth cells are not found in adults |
|
Definition
| what is the mucosal epithelium of the colon like? |
|
|
Term
| no, but the colon still has MALT |
|
Definition
| are peyer's patches or lymph vessels found in the colon? |
|
|
Term
| every 5 days, stem cells are at the base of the crypts |
|
Definition
| how often are epithelial cells replaced in the colon? |
|
|
Term
| its reduced or incomplete and forms 3 strips called taenia coli |
|
Definition
| what is special about the longitudinal layer of the muscularis externa in the colon? |
|
|
Term
| taenia coli form the haustra which are sacculations of the large intestine |
|
Definition
| what forms haustra? what are haustra? |
|
|
Term
|
Definition
| any mass arising from the wall of the colon that protrudes into the lumen |
|
|
Term
| usually they are asymptomatic, but rectal bleeding is the most common sign |
|
Definition
| whats the most common sign of polyps? |
|
|
Term
| adenocarcinoma, in can be prevented by increased fiber/roughage, which decreases transit time and increases GI motility (stuff moves faster so less time to absorb toxins) |
|
Definition
| what is another name for colon cancer? what can supposedly prevent it? |
|
|
Term
|
Definition
| short, dilated terminal portion of large intestine |
|
|
Term
| transverse rectal folds & longitudinal folds called anal columns or columns of Morgani |
|
Definition
| describe the folds of the rectum |
|
|
Term
|
Definition
| where in the GI tract is the transition of mucosa from simple columnar epithelium to stratified squamous epithelium? |
|
|
Term
|
Definition
| with in the anal canal _______ extend into the submucosa and muscularis externa (these are branched , straight, tubular glands that secrete mucus) |
|
|
Term
internal = involuntary
external = voluntary |
|
Definition
| muscle surrounding the rectum forms the internal and external anal sphincters, which is voluntary skeletal muscle, and which is involuntary smooth? |
|
|
Term
| hemorrhoids - they are like varicose veins |
|
Definition
| occasional enlargement and irritation of submucosal veins around the anal canal |
|
|
Term
term given to metaplastic columnar epithelium at risk of developing dysplasia and invasive adenocarcinoma
(due to repeat healing from acid damage) |
|
Definition
| what is Barrett's oesophagus? |
|
|
Term
immunologic response to gluten, that causes loss of intestinal villi, and increase in plasma cells & lymphocytes, and marked increase in intraepithelial t lymphocytes
get symptoms of malabsorbtion....inspecific |
|
Definition
| what is Celiac's disease/sprue/ gluten sensitive enteropathy? |
|
|
Term
| if you have bone marrow problems, people get liver and spleen hematopoetic sites causing those organs to enlarge |
|
Definition
| what is extramedullary hematopoesis? |
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|
