During the normal events of the cardiac cycle, which of the following statements is true?
a. Electrical depolarization follows mechan-ical contraction.
b. Electrical depolarization precedes me-chanical contraction.
c. Heart sounds precede electrical depolari-zation.
d. Heart sounds precede cardiac valve open-ing or closing.
ANS: B
The P wave signals atrial depolarization. Within 0.1 sec, the atria contract, causing a slight rise in both atrial and ventricular pressures (the A waves).
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A ________ practices medicine, which is the science of diagnosis, treatment, and prevention of disease, and requires a minimum of nine to ten years of education and training
a. doctor (MD) b. registered nurse (RN) c. registered medical assistant (RMA) d. licensed practical nurse (LPN)
Privileges for licensed independent practitioners are granted for a period not to exceed
A. three years B. two years C. one year