During an annual health examination of a 46-year-old woman, a physician finds hyper- secretion of norepinephrine from her supra- renal medulla. Which of the following types of nerve fibers are most likely overstimulated?
(A) Preganglionic sympathetic fibers
(B) Postganglionic sympathetic fibers
(C) Somatic motor fibers
(D) Postganglionic parasympathetic fibers
(E) Preganglionic parasympathetic fibers
Answer: (A) Preganglionic sympathetic fibers
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Indicate whether the statement is true or false
Late one night, while studying for your anatomy class, you open a box of saltine crackers to do a little snacking. After chewing on a starchy morsel for a few minutes, you begin to notice a sweet taste in your mouth. What accounts for this?
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Red blood cells (RBCs) have been placed in three different solutions: hypotonic, hypertonic, isotonic. What is the condition of the RBC in solution "C"?
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Which best describes an event that occurs as part of the crossed-extensor reflex?
A. It stimulates contraction of the contralateral flexor and inhibits contraction of the contralateral extensor. B. It stimulates contraction of the contralateral extensor and inhibits contraction of the contralateral flexor. C. It is initiated by stretch in the ipsilateral extensor muscle. D. Inhibitory interneurons are activated, which synapse onto contralateral extensor muscles. E. Monosynaptic excitatory stimulation of ipsilateral extensor muscles occurs.