Study Questions - Dr. Sanchez (16Q) Flashcards
(20 cards)
Which of the following is a true fundamental concept of the enteric nervous system?
a. the ENS controls motility, endocrine and exocrine secretions within the GI tract
b. the ENS requires CNS control for all of its functions
c. microcirculation within the intestine is controlled by the CNS without ENS input
d. the ENS functions as an “all-knowing” entity without allowing for feedback control or reflexive responses
a. the ENS controls motility, endocrine and exocrine secretions within the GI tract
Which of the following is true regarding innervation within the ENS?
a. the primary role of the submucous plexus is motor innervation
b. the myenteric plexus is located between the mucosa and circular muscle layers
c. the myenteric plexus is best developed in the small intestine
d. the submucous plexus plays a role in intestinal secretion
d. the submucous plexus plays a role in intestinal secretion
Which of the following neurons projects from the ENS to the brainstem (or spinal cord) to initiate central modulatory responses?
a. intrinsic primary afferent neuron
b. extrinsic primary afferent neuron
c. interneuron
d. enteric motor neuron
b. extrinsic primary afferent neuron
Regarding enteric motor neurons, which of the following neurotransmitters is primarily excitatory for post-ganglionic parasympathetic fibers?
a. norepinephrine
b. vasoactive intestinal peptide (VIP)
c. acetylcholine (ACh)
d. nitric oxide (NO
c. acetylcholine (ACh)
In which type of glandular mucosa are parietal cells located?
a. fundic
b. astral
c. cardiac
a. fundic
Fundic = PC, CC, ECL, DC Pyloric = DC, CC, GC
Which of the following statements is correct regarding the mechanism of acid secretion?
a chloride content in the canaliculus is typically the limiting factor for overall acid secretion
b. chloride is actively secreted through a chloride-calcium ATPase pump
c. hydrogen ions are passively secreted through an ion channel
d. stimulation of the parietal cell results in a morphologic change in the cell such that cytoplasmic tubules disappear and a secretory cannaliculus develops
d. stimulation of the parietal cell results in a morphologic change in the cell such that cytoplasmic tubules disappear and a secretory cannaliculus develops
Which of the following statements is correct regarding neural regulation of acid secretion?
a. acetylcholine can stimulate acid secretion indirectly by stimulating the ECL cell via M1 receptor
b. acetylcholine can stimulate acid secretion directly via H2 receptor
c. acetylcholine can stimulate acid secretion indirectly by stimulating the D cel
d. acid secretion cannot be stimulated by the CNS
a. acetylcholine can stimulate acid secretion indirectly by stimulating the ECL cell via M1 receptor
Which of the following is true regarding regulation of acid secretion?
a. somatostatin, produced by the D cell, is the major paracrine stimulus for acid secretion
b. gastric distension stimulates acid secretion directly by stimulating histamine secretion from the ECL cell
c. Histamine secretion by the ECL cell is stimulated by acetylcholine and gastrin and will stimulate acid secretion
d. acidification of gastric contents stimulates the release of gastrin from the G cell, which in turn stimulates acid secretion
c. Histamine secretion by the ECL cell is stimulated by acetylcholine and gastrin and will stimulate acid secretion
Which of the following statements is true regarding gastric motility and emptying?
a. in the canine stomach, slow wave activity typically starts at the pylorus
b. the rate of liquid gastric emptying is primarily determined by propagating peristaltic wave activity and is typically slower than that of solids
c. during the process of ingestion, the stomach contracts in response to swallowed food
d. trituration is accomplished by retropulsion of large particles from the pylorus back into the fundus by propagating peristaltic wave activity
d. trituration is accomplished by retropulsion of large particles from the pylorus back into the fundus by propagating peristaltic wave activity
Which of the following statements is true regarding pepsin?
a. its conversion from pepsinogen is stimulated by luminal pH <4.0
b. it is secreted in the active form
c. it will not aggravate an ulcerogenic process
d. it is secreted by the parietal cell
a. its conversion from pepsinogen is stimulated by luminal pH <4.0
Which of the following statements is true regarding the gastric mucosal barrier?
a. all types of gastric mucosa secrete mucus and bicarbonate, which are important components of the barrier
b. in addition to secreting mucus and bicarbonate secretion, prostaglandin E2 also enhances the mucosal barrier by increasing mucosal perfusion
c. cellular turnover within gastric mucosal epithelium is extremely slow, contributing to mucosal protection
d. the mucosal barrier helps regulate the change from a luminal pH of 7-7.5 to a mucosal pH of 1-2
b. in addition to secreting mucus and bicarbonate secretion, prostaglandin E2 also enhances the mucosal barrier by increasing mucosal perfusion
a. all types of gastric mucosa secrete mucus and bicarbonate, which are important components of the barrier - incorrect, only glandular
What is the biggest source of bilirubin in the body?
a. neutrophils
b. muscle
c. red blood cells
d. bone
c. red blood cells
Your are presented with a 5 y/o QH mare with a primary complaint of lethargy. During your PE, you keenly notice that the mare’s sclera are moderately incteric. Her total bilirubin is 11.2mg/dl. During an ultrasound exam of her abdomen, you notice that her bile ducts are enlarged and you therefore suspect cholelithiasis resulting in an obstructive hyperbilirubinemia. If you were to request fractionated bilirubin analysis, which fraction would likely be primarily elevated?
a. free
b. conjugated
c. both
d. neither
b. conjugated
Which of the following species will fasting most likely cause hyperbilirubinemia and icterus?
a. equine
b. bovine
c. canine
d. feline
a. equine
Within the cycle of bilirubin metabolism, which of the following is usually the rate-limiting step in most species?
a. reduction of biliverdin to free bilirubin
b. absorption of free bilirubin by hepatocytes
c. secretion of conjugated bilirubin into bile
d. absorption of conjugated bilirubin within the intestine
c. secretion of conjugated bilirubin into bile
Which product of bilirubin metabolism is excreted in the feces?
a. conjugated bilirubin
b. urobilinogen
c. urobilin
d. stercobilin
d. stercobilin
Name 3 major non-immunological factors important which provide protection against enteric pathogens.
saliva, digestive enzymes, motility
Which of the following is NOT a normal response to normal GI contents (normal flora, self- or food-antigens)?
a. cell activation and recruitment
b. inflammation
c. anergy
d. immune suppression
b. inflammation
Which of the following statements is correct regarding peyer’s patches and associated cells?
a. transport at the M cell is slow because it is extremely selective
b. immunoglobulin transport by M cells is primarily Fc-receptor mediated
c. M cells increase in number in response to antigen stimulation
d. M cells are the only antigen-presenting cells in the gastrointestinal associated lymphoid tissue
c. M cells increase in number in response to antigen stimulation
The gastrointestinal tract is the major source of which of the following immunoglobulin classes?
a. IgG
b. IgM
c. IgE
d. IgA
d. IgA
