Verne is suffering from cardiac arrhythmias and is brought into the emergency room of a hospital. In the emergency room, he begins to exhibit tachycardia and as a result loses consciousness. His anxious wife asks why he has lost consciousness. What should the attending physician say to Verne's wife?
What will be an ideal response?
During tachycardia, the heart beats at an abnormally fast rate. The faster the heart beats, the less time there is between contractions for the chamber to fill with blood again. As a result, over a period of time the heart fills with less and less blood and thus pumps less blood out. The stroke volume decreases, as does the cardiac output. When the cardiac output decreases to the point where not enough blood reaches the central nervous system, loss of consciousness occurs.
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A. endochondral ossification. B. orthodontia. C. mesenchymal ossification. D. bone remodeling. E. intramembranous ossification.
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A. parietal; visceral B. respiratory; pleural C. visceral; parietal D. fibrous; serous E. thoracic; pulmonary
The descending __________ tract carries signals for precise, coordinated limb movements.
Fill in the blank(s) with the appropriate word(s).