Problem
Lauren is a 27-year-old assistant manager at a discount department store. One morning, she awakened from a deep sleep and realized that she was more than an hour late for work. She panicked, momentarily regretting her late-night socializing, and then jumped out of bed. Briefly, she felt lightheaded and thought she might faint. She had the sensation that her heart was "racing." Had she not been so late for work, she would have returned to bed. As she walked toward the bathroom, she noticed that her light-headedness dissipated. The rest of her day was uneventful.
Task
• When Lauren moved rapidly from a supine (lying) position to a standing position, there was a brief, initial decrease in arterial pressure that caused her light-headedness. Describe the sequence of events that produced this transient fall in arterial pressure.
• Why did the decrease in arterial pressure cause Lauren to feel light-headed?
• Lauren's light-headedness was only transient because a reflex was initiated that rapidly restored arterial pressure to normal. Describe the specific effects of this reflex on heart rate, myocardial contractility, and capacitance of the veins. What receptors are involved in each of these responses?
• In addition to the reflex correction of blood pressure, the fact that Lauren walked to the bathroom helped return her arterial pressure to normal. How did walking help?
The response should include a reference list. One-inch margins, Using Times New Roman 12 pnt font, double-space and APA style of writing and citations.