Week 5- Digestive Flashcards
activities of the digestive system are controlled by ______ and __________-
hormones
autonomic nervous system.
Layers of digestion system
(inside out)
mucosa
submucosa
muscularis
serosa
Neurons forming the ________ nervous system are located solely within the GI tract and are controlled by local and autonomic nervous system stimuli
enteric
who makes Secretory IgA
goblet cells, Paneth cells, and plasma cells.
The________ plexus mainly regulates motility through relaxation and contraction of the intestinal wall
myenteric
The__________ plexus senses the lumen environment and regulates gastrointestinal blood flow as well as controlling the epithelial cell functions and secretion.
submucosal
____________-is stimulated when afferent fibers distributed along the length of the esophagus sense changes in wall tension caused by stretching as food passes
Peristalsis
prevents entry of air into the esophagus during respiration
The upper esophageal sphincter (UES)
prevents regurgitation from the stomach
lower esophageal sphincter (LES)
voluntary phase of swallowing
oralpharyngeal
involuntary phase of swallowing
esophageal
difficulty swallowing that results from mechanical obstruction of the esophagus or a functional disorder that impairs esophageal motility
dysphasia
dysphagia can be from intrinsic and extrinsic cause, what’s the difference
intrinsic= tumor or mass is part of the esohpagus
extrinsic= mass is not a part of the esophagus
caused by neural or muscular disorders that interfere with voluntary swallowing or peristalsis
functional dysphagia
Discomfort occurring 2 to 4 seconds after swallowing is associated with
upper esophageal obstruction.
Discomfort occurring 10 to 15 seconds after swallowing is more common in obstructions of the
lower esophagus.
Dysphagia DX Tests
- Barium swallow
- Esophageal endoscopy
- CT scan
reflux of acid and pepsin from the stomach to the esophagus that causes esophagitis
GERD ( Gastroesophageal Reflux Disease)
Risk factors for GERD include
- obesity
-hiatal hernia
-drugs or chemicals that relax the LES
The resting tone of the________ tends to be lower than normal from either transient relaxation or weakness of the sphincter in those who develop GERD.
LES (lower esophageal sphincter)
Precancerous lesions associated with GERD
Barrett esophagus
Clinical Manifestations of GERD
-heartburn from acid regurgitation
-chronic cough, asthma attacks and laryngitis
-Upper abdominal pain usually occurs within 1 hour of eating
-worse with laying down
GERD treatment
-PPI
-histamine-2 (H2) receptor antagonists, -prokinetics antacids.
-Elevation of the head of the bed 6 inches prevents reflux
-Weight reduction
-stop smoking
-rare, idiopathic inflammatory disease of the esophagus
-characterized by esophageal infiltration of eosinophils associated with atopic disease, including asthma and food allergies
Eosinophilic Esophagitis
necessary for the intestinal absorption of vitamin B12
intrinsic factor
facilitates small intestinal absorption of iron.
gastroferrin
secrete hydrochloric acid, intrinsic factor, and gastroferrin.
parietal cells
secret pepsinogen
chief cells
synthesizes and releases the hormone gastrin from G cells
pyloric gland mucosa
secrete histamine
Enterochromaffin-like cells
secrete somatostatin (an inhibitory hormone for the release other hormones throughout body)
D cells
major functions of gastric hydrochloric acid
dissolve food fibers, act as a bactericide against swallowed organisms, and convert pepsinogen to pepsin.
Acid secretion by parietal cells is stimulated by
- acetylcholine (ACh)
- gastrin
- histamine
strongest stimulation for pepsin secretion
acetylcholine (ACh)
proteolytic enzyme that breaks down protein forming polypeptides in the stomach
pepsin
what degrades stomach mucus
-aspirin or other nonsteroidal anti-inflammatory drugs
-Helicobacter pylori
-ethanol
-regurgitated bile
- ischemia
Breaks cause inflammation and ulceration.
where is B12 absorbed
ileum
a gram-negative spiral bacterium with a flagella and is a major cause of acute and chronic gastritis, peptic ulcer disease in the duodenum and stomach, gastric adenocarcinoma, and gastric mucosa–associated lymphoid tissue (MALT)
H pylori
H PYLROI transmission
transmitted through the fecal-oral route and is usually acquired in childhood
