Multiple Choice
The normal pacemaker of the heart is the __________.
18. The Heart
Electrical Conduction System of the Heart
Back18. The Heart
Electrical Conduction System of the Heart
- Multiple Choice
Which feature of cardiac tissue allows for the rapid spread of action potentials through the heart?
- Multiple Choice
Which statement best describes intrinsic conduction of the heart?
- Multiple Choice
The intrinsic conduction system ensures a coordinated and efficient heartbeat. If the sinoatrial (SA) node malfunctions, which part of the heart’s conduction system is most likely to take over as the pacemaker?
- Multiple Choice
Which answer choice below correctly matches the cardiac conduction structure to where it’s found in the heart?
- Multiple Choice
The AV node has fewer gap junctions than the SA node, leading to slower conduction. How does this slower conduction help the heart function?
- Multiple Choice
What is the primary function of the pacemaker cells in the SA node in the heart?
- Multiple Choice
Which structure or structures are most directly responsible for allowing contraction of the ventricles to begin at the apex of the heart rather than in the septum closer to the AV node?
- Multiple Choice
Which center in the medulla oblongata controls the sympathetic neurons that stimulate the heart?
- Multiple Choice
Which statement best describes a difference between how the sympathetic and parasympathetic nervous system affects the heart?
- Multiple ChoiceWhich of the following is a difference between cardiac muscle and skeletal muscle?
- Multiple ChoiceThe contractile cardiac muscle fibers of the myocardium behave as a single, coordinated unit called a __________.
- Multiple ChoiceWhich of the following factors gives the myocardium its high resistance to fatigue?
- Open QuestionThe autonomic division of the nervous system directs (a) voluntary motor activity, (b) conscious control of skeletal muscles, (c) unconscious control of skeletal muscles, (d) processes that maintain homeostasis, (e) sensory input from the skin.
- Open QuestionWhich four ganglia serve as origins for postganglionic fibers involved in control of visceral structures in the head?