PATHOPHYSIOLOGY--NU545-- UNIT 6-- GI EXAM
QUESTIONS AND ANSWERS WITH COMPLETE
SOLUTIONS GRADED A++
Enteric Plexus
Intrinsic nerves are located solely within the GI tract and are controlled by local and autonomic nervous
system stimuli through the enteric plexus, which comprises 3 nerve plexuses located in different layers of
the GI walls.
-these enteric nerve circuits regulate motility reflexes, blood flow, absorption, secretions, and immune
responses.
Submucosal Plexus
Meissner plexus. Intrinsic nerve located soley in the GI tract and is controlled by the ANS. Located in the
muscularis mucosae
Myenteric Plexus
Auerback plexus. Intrinsic nerve located soley in the GI tract and is controlled by the ANS. Located b/w
the inner circular and outer longitudinal muscle layers (tunica muscularis).
Subserosal Plexus
Located just beneath the serosa. Intrinsic nerve located soley in the GI tract and is controlled by the ANS.
Upper esopagheal sphincter
(cricopharyngeal muscle) prevents entry of air into the esophagus during respiration.
,Lower esophageal sphincter (LES)
(cardiac sphincter) prevents regurgitation from the stomach; located near the esophageal hiatus—the
opening in the diaphragm where the esophagus ends at the stomach.
Peritoneal cavity
Space b/w the visceral peritoneum and parietal perioteneum; normally contains just enough fluid to
lubricate the 2 layers and prevent friction during organ movement.
Dumping Syndrome
The rapid emptying off hypertonic chime from the surgically created, residual stomach into the small
intestine 10 to 20 minutes after eating (early dumping syndrome).
Saliva
Secreted in the mouth. Consists mostly of water that contains varying amounts of mucus; sodium;
bicarbonate; chloride; potassium; and salivary alpha-amylase (ptyalin).
Ptyalin
An enzyme that initiates carbohydrate digestion in the mouth and stomach.
Saliva
The bicarbonate concentration sustains a pH of about 7.4, which neutralizes bacterial acids and prevents
tooth decay.
Viral Hepatitis
A relatively common systemic disease that affects primarily the liver.
Fulminant hepatitis
, A clinical syndrome resulting in severe impairment or necrosis of liver cells and potential liver failure.
Hepatitis G
-discovered in the 1990s
-parenterally and sexually transmitted
-may decrease HIV viral load, increase CD4+T cell levels, and slow down HIV disease progression
-NO association with hepatocellular carcinoma
Hepatitis E
-transmitted by the fecal-oral route or by contaminated water
-found in developed countries and must be differentiated from drug-induced liver injury
-animal reservoirs of HEV include: domestic pigs, wild boars, and deer
-more prevalent among adults and has the highest mortality rate among pregnant women
-no vaccine for HEV but in progress
Hepatitis D
-the delta virus depends on HBV for its replication because the coat of the delta virus consists of HBsAg
molecules that are on the surface of HBV
-shown to suppress replication of HBV
-parenteral drug users have high incidence of HDV
-clinical course is similar to hep. A and B (although sometimes more severe)
-treatment for chronic HDV may best be treated with antiviral drugs.
Hepatitis C
-previously known as non-A, non-B hepatitis--a parenterally transmitted flavivirus with 6 genotypes--40%
of cases involve IV drug users (with high incidence of HIV)--co-infection with HBV is prevalent--most
QUESTIONS AND ANSWERS WITH COMPLETE
SOLUTIONS GRADED A++
Enteric Plexus
Intrinsic nerves are located solely within the GI tract and are controlled by local and autonomic nervous
system stimuli through the enteric plexus, which comprises 3 nerve plexuses located in different layers of
the GI walls.
-these enteric nerve circuits regulate motility reflexes, blood flow, absorption, secretions, and immune
responses.
Submucosal Plexus
Meissner plexus. Intrinsic nerve located soley in the GI tract and is controlled by the ANS. Located in the
muscularis mucosae
Myenteric Plexus
Auerback plexus. Intrinsic nerve located soley in the GI tract and is controlled by the ANS. Located b/w
the inner circular and outer longitudinal muscle layers (tunica muscularis).
Subserosal Plexus
Located just beneath the serosa. Intrinsic nerve located soley in the GI tract and is controlled by the ANS.
Upper esopagheal sphincter
(cricopharyngeal muscle) prevents entry of air into the esophagus during respiration.
,Lower esophageal sphincter (LES)
(cardiac sphincter) prevents regurgitation from the stomach; located near the esophageal hiatus—the
opening in the diaphragm where the esophagus ends at the stomach.
Peritoneal cavity
Space b/w the visceral peritoneum and parietal perioteneum; normally contains just enough fluid to
lubricate the 2 layers and prevent friction during organ movement.
Dumping Syndrome
The rapid emptying off hypertonic chime from the surgically created, residual stomach into the small
intestine 10 to 20 minutes after eating (early dumping syndrome).
Saliva
Secreted in the mouth. Consists mostly of water that contains varying amounts of mucus; sodium;
bicarbonate; chloride; potassium; and salivary alpha-amylase (ptyalin).
Ptyalin
An enzyme that initiates carbohydrate digestion in the mouth and stomach.
Saliva
The bicarbonate concentration sustains a pH of about 7.4, which neutralizes bacterial acids and prevents
tooth decay.
Viral Hepatitis
A relatively common systemic disease that affects primarily the liver.
Fulminant hepatitis
, A clinical syndrome resulting in severe impairment or necrosis of liver cells and potential liver failure.
Hepatitis G
-discovered in the 1990s
-parenterally and sexually transmitted
-may decrease HIV viral load, increase CD4+T cell levels, and slow down HIV disease progression
-NO association with hepatocellular carcinoma
Hepatitis E
-transmitted by the fecal-oral route or by contaminated water
-found in developed countries and must be differentiated from drug-induced liver injury
-animal reservoirs of HEV include: domestic pigs, wild boars, and deer
-more prevalent among adults and has the highest mortality rate among pregnant women
-no vaccine for HEV but in progress
Hepatitis D
-the delta virus depends on HBV for its replication because the coat of the delta virus consists of HBsAg
molecules that are on the surface of HBV
-shown to suppress replication of HBV
-parenteral drug users have high incidence of HDV
-clinical course is similar to hep. A and B (although sometimes more severe)
-treatment for chronic HDV may best be treated with antiviral drugs.
Hepatitis C
-previously known as non-A, non-B hepatitis--a parenterally transmitted flavivirus with 6 genotypes--40%
of cases involve IV drug users (with high incidence of HIV)--co-infection with HBV is prevalent--most
