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SECTION IV. GASTROINTESTINAL PHYSIOLOGY
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Water is absorbed in the jejunum, ileum, and colon and excreted in the feces. Arrange these in order of the amount of water absorbed or excreted from greatest to smallest.
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A. Colon, jejunum, ileum, feces
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B. Feces, colon, ileum, jejunum
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C. Jejunum, ileum, colon, feces
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D. Colon, ileum, jejunum, feces
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E. Feces, jejunum, ileum, colon
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Following a natural disaster in Haiti, there is an outbreak of cholera among displaced persons living in a tent encampment. The affected individuals display severe diarrheal symptoms because of which of the following changes in intestinal transport?
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A. Increased Na+–K+ cotransport in the small intestine
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B. Increased K+ secretion into the colon
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C. Reduced K+ absorption in the crypts of Lieberkühn
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D. Increased Na+ absorption in the small intestine
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E. Increased Cl− secretion into the intestinal lumen
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A 50-year-old man comes to see his clinician complaining of severe epigastric pain, frequent heartburn, and unexplained weight loss of 20 pounds over a 6-month period. He claims to have obtained no relief from over-the-counter H2 antihistamine drugs. He is referred to a gastroenterologist, and upper endoscopy reveals erosions and ulcerations in the proximal duodenum and an increased output of gastric acid in the fasting state. The patient is most likely to have a tumor secreting which of the following hormones?
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Which of the following has the highest pH?
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B. Colonic luminal contents
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E. Contents of the intestinal crypts
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A 60-year-old woman undergoes total pancreatectomy because of the presence of a tumor. Which of the following outcomes would not be expected after she recovers from the operation?
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