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Chapter 21. Hormonal Control of Calcium & Phosphate Metabolism & the Physiology of Bone
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A patient with parathyroid deficiency developing 10 days after inadvertent damage to the parathyroid glands during thyroid surgery would probably have
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A. low plasma phosphate and Ca2+ levels and tetany.
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B. low plasma phosphate and Ca2+ levels and tetanus.
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C. a low plasma Ca2+ level, increased muscular excitability, and spasm of the muscles of the upper extremity (Trousseau sign).
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D. high plasma phosphate and Ca2+ levels and bone demineralization.
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E. increased muscular excitability, a high plasma Ca2+ level, and bone demineralization.
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In an experiment, a rat is infused with a small volume of a calcium chloride solution, or sodium chloride as a control. Compared to the control condition, which of the following would result from the calcium load?
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B. Increased formation of 1,25-dihydroxycholecalciferol
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C. Decreased secretion of calcitonin
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D. Decreased blood coagulability
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E. Increased formation of 24,25-dihydroxycholecalciferol
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In the same rat, which of the following would be increased?
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A. Intestinal absorption of calcium
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B. Expression of TRPV5 in the renal proximal tubule
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C. NaPi-IIb abundance in the enterocyte apical membrane
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D. Urinary excretion of calcium
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E. Expression of calbindins
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Which of the following is not involved in regulating plasma Ca2+ levels?
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1,25-Dihydroxycholecalciferol affects intestinal Ca2+ absorption through a mechanism that
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A. includes alterations in the activity of genes.
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B. activates adenylyl cyclase.
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C. decreases cell turnover.
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D. changes gastric acid secretion.
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E. involves degradation of apical calcium channels.
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Which of the following would you expect to find in a patient whose diet has ...