Once cells in the SA node reach threshold,
A. nothing happens until the AV node is innervated.
B. the heart stops beating.
C. an action potential is triggered.
D. a heart attack occurs.
Answer: C
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Which is defined as the amount of air that remains in the lungs after a maximum exhalation?
A) minimal volume B) inspiratory reserve volume C) vital capacity D) expiratory reserve volume E) residual volume
Describe the importance of afferent visceral information in normal ANS function
What will be an ideal response?
________ is the volume of air inspired during a normal inspiration.
Fill in the blank(s) with the appropriate word(s).
An autorhythmic heart cell is one in which
A. action potentials always occur at exactly the same frequency. B. action potentials are stimulated by internal stores of acetylcholine. C. action potentials fire spontaneously. D. action potentials are initiated by the autonomic nervous system. E. all filaments contract and relax with a high degree of synchrony.