Flashcards in GI Deck (71)
What is the major function of the GI system?
Why is the GI tract susceptible , and how does this compare to the respiratory tract?
Both the GI and respiratory tract are open to the environment
-Susceptible for invasion by microbes
What are examples of your bodies defenses that help protect your GI and respiratory tract?
-Normal flora (to outcompete most ingested microbes)
What are the 4 layers of the digestive tract? (inner to outer)
-Muscle (longitudinal and circular)
Describe the function of teeth
Teeth break down food by tearing and grinding it
Describe the function of saliva (what does it specifically start to break down?)
Saliva begins carbohydrate digestion
Describe how food gets to the stomach?
Esophagus moves food bolus to the stomach via peristalsis
What are the 3 things that are leased by the stomach?
What does pepsinogen do?
Begins protein digestion
What does gastrin do?
-Stimulates gastric acid secretion
-Stimulates pancreatic enzyme release
-Liver bile production
What does Somatostatin do?
-Inhibits insulin secretion
What produces Somatostatin?
The small intestine receives 3 components to help in digestion?
What does bile do?
What does pancreatic amylase and lipase do?
Fat and carbohydrate digestion
What allows the SI to absorb large amounts?
Large surface area with villi and microvilli for ABSORPTION
What does the LI do?
-Absorb water and electrolytes
-Compacts feces and transports them to the rectum for storage
Where are wastes emptied from?
Describe the mesentery
-Double layered sheet of peritoneum that SUSPENDS THE BOWEL and ATTACHES IT TO THE BODY WALL
What provides a path for arteries and veins to an from the GI tract?
These are macroscopic folds in the SI that help add to the increase in surface area?
_____ are numerous and on the mucosal surface
The small intestine also contains _________
Submucosal collections of lymphoid tissue (Peyer patches)
What covers each villus?
Columnar epithelial cells with a "BRUSH BORDER" of microvilli
(Further increases surface area)
These are mucus secreting cells that are spread out in the intestinal epithelium
_______ is caused by bacteria that erode enamel and invade tooth structure (arguably the most common disease in the world).
______ results from bacterial invasion of gingival pockets around the tooth root
______ is inflammation of the superficial gums, leading to retraction and exposure of the root
What is the root cause of periodontitis
Bacterial invasion downward into the soft tissues around the tooth root
These are small shallow ulcers of unknown etiology that heal quickly
-Also known are Canker sores
T/F- Most people have been infected by oral herpesvirus by age 5
Why/how does reactivation of oral herpesvirus occur?
-Reactivation as cold sores or fever blisters
-Actually represent the reactivation and replication of the dormant virus from within the nerve tissue (usually the trigeminal ganglion)
What are 3 main causes of thrush?
Can you scrape off thrush?
This is a white patch of oral squamous mucosa
What can leukoplakia lead to?
-Squamous cell carcinoma
What are the major risk factors for leukoplakia and squamous cell carcinoma?
What areas in the mouth are these located and often missed on examination?
-Under the tongue on the floor of the oral cavity
-Survival rates here are worse than the lip
This is inflammation of the salivary glands
What causes sialadenitis?
-Sialolith (calcified stone most common in SUBMANDIBULAR GLAND)
What are other causes of sialadentis?
-Bacteria (S. aureus)
-Virus (mumps-effects parotid gland- but yes vaccine)
This is a salivary and lacrimal gland autoimmune inflammation
What are S&S for Sjögren syndrome
This is a tumor, mostly benign, of the salivary glands
What salivary gland is most effected by pleomorphic adenoma
Parotid gland- removal is difficult because due to the fear of damaging facial nerves
What are some symptoms of esophageal disease?
-Odynophagia (pain with swallowing)
______ is a spastic (increased muscle tone) condition of the lower esophageal sphincter
What does Achalasia produce?
-Functional partial obstruction in the lower esophagus
-Causes dysphagia and esophageal pain
______ is a protrusion of the cardia region of the stomach through the esophageal hiatus into the thoracic cavity
What are S&S for hiatal hernias?
________ is lacerations in the esophagus secondary to retching/vomiting (e.g. bulimia, alcoholism).
This is esophageal rupture
_______ are dilated veins due to re-routing of blood from the portal circulation back to the systemic circulation (they form for the same reasons that hemorrhoids form)
Patients with ______ often have esophageal varices
Describe why esophageal varices occur in cirrhosis
-Lower esophagus veins drain into the IVC or gastric/portal vein
-Goes through the liver
-Liver becomes fibrotic in cirrhosis
-Back up of portal blood
-Esophageal veins become more dilated and prone to rupture
-Most common GI disorder
-Backward movement of gastric contents to the esophagus
Fancy word for heart burn
What are some risks for GERD
Explain the progression from normal to Barretts esophagus
-Weak esophageal sphincter
-Reflux of gastric contents
-Inflammation and hyperemia
-Metaplasia aka Barretts esophagus
Normal esophagus epithelium= _______ cells
Normal stomach epithelium= _______ cells
S&S of Barretts esophagus
-Narrowing because of fibrous scars
Risk factors for Barretts esophagus
What is the most common cancer from Barretts esophagus?
-Esophageal squamous cell carcinoma
This is inflammation of the gastric mucosa
What cause gastritis?
Pathogenesis of gastritis
-Mucosal breakdown and repeated acid injury
-Acute inflammatory response
-Bleeding may occur
These are multiple superficial ulcers in patients with brain injury
Acute gastric ulcers
What color is the blood on the ulcers surface in an acute gastric stress ulcer
Black- due to the acid environment
Are acute stress ulcers superficial or deep?