Asked by Peter Ivery on May 25, 2024
Verified
The cardiac electrical impulse normally begins spontaneously in the SA node because
A) of the superior location of the SA node in the right atrium.
B) the SA node is the only area of the heart capable of spontaneous depolarization.
C) of the rich sympathetic innervation of the SA node.
D) this area produces action potentials more rapidly than any other portion of the conduction system.
E) of action potentials from the cardioregulatory center.
SA Node
The sinoatrial node, a group of cells in the right atrium of the heart that sets the pace for the heart rate by generating electrical impulses.
Spontaneous Depolarization
The self-initiated transition of a cell's membrane potential to a less negative value.
Cardiac Electrical Impulse
The electrical signals that stimulate the heart to contract, crucial for maintaining a consistent heart rhythm.
- Describe the principal components and their duties in the cardiac conduction system.
- Ascertain the determinants affecting and adjusting cardiac performance.
Verified Answer
JA
Jeffrey AtkinsonMay 29, 2024
Final Answer :
D
Explanation :
The SA node (sinoatrial node) acts as the natural pacemaker of the heart because its cells can generate action potentials more rapidly than other parts of the heart's conduction system, ensuring a consistent heart rhythm under normal conditions.
Learning Objectives
- Describe the principal components and their duties in the cardiac conduction system.
- Ascertain the determinants affecting and adjusting cardiac performance.