The pacemaker of the heart is normally which structure?
a. atrioventricular (AV) node
b. sinoatrial (SA) node
c. mitral valve
d. bundle of His
e. left ventricle
Answer: b. sinoatrial (SA) node
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Cerebral lateralization refers to the
A. difficulty in assigning a precise function to a specific region of the cortex. B. generalization that both cerebral hemispheres receive their sensory information from and project motor commands to the opposite side of the body. C. separation of the various lobes of the brain from each other. D. crisscrossing of information between the two hemispheres. E. functional differences between the right and left hemispheres.
The pelvic inlet of the female pelvis is ________.
A. more than 90o B. less than 90o C. oval-shaped D. heart-shaped
Mary is 50 years old and has entered menopause. During a checkup, a bone scan reveals the beginnings of osteoporosis. Her physician suggests hormone therapy. What hormone might she prescribe for Mary?
A) thyroid hormone B) growth hormone C) estrogen D) parathyroid hormone E) calcitonin
When smooth muscle is stretched for a prolonged period of time, it responds by
A. relaxing. B. contracting.