A patient faints if he gets up out of bed too quickly. Which one of the following events would most likely account for such fainting? A) Reduced baroreflex function. B) Exaggerated increase in renal sympathetic nerve activity. C) A baroreflex-mediated reduction in heart rate. D) Increased blood pressure. E) Activation of the Cushing response. 2. Mean arterial pressure readings over 3 months are between 95 and 105 mmHg for patient X and between 140 and 150 mmHg for patient Y. What is the effect of a rapid decrease in carotid sinus pressure? A) Increase in both sympathetic and parasympathetic nerve activity only in patient X. B) Increase in sympathetic and decrease parasympathetic nerve activity only in patient X. C) Increase in firing in the baroreceptor afferents about equally in both patients. D) Increase in plasma renin activity only in patient Y. E) Decrease in parasympathetic nerve activity about equally in both patients.
Added by Rhonda R.
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The correct answer is A) Reduced baroreflex function. Baroreceptors are specialized nerve endings located in the walls of blood vessels that detect changes in blood pressure. When blood pressure drops, baroreceptors send signals to the brain to increase heart rate Show more…
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