MDCAT Physics MCQ #632

A person uses a cardiac pacemaker to regulate their heartbeat. What is the primary mechanism of the pacemaker's action?

MDCAT Physics MCQ #632

  1. Question 1

    Q1. A person uses a cardiac pacemaker to regulate their heartbeat. What is the primary mechanism of the pacemaker's action?

    • A) The pacemaker generates an electrical signal that stimulates the sinoatrial node to fire.
    • B) The pacemaker generates an electrical signal that blocks the sinoatrial node's natural firing.
    • C) The pacemaker generates an electrical signal that modulates the release of neurotransmitters involved in heart rhythm regulation.
    • D) The pacemaker generates an electrical signal that increases the strength of the sinoatrial node's natural firing.

    Answer: The pacemaker generates an electrical signal that stimulates the sinoatrial node to fire.

    Explanation: The pacemaker generates an electrical signal that stimulates the sinoatrial node to fire, ensuring a regular heartbeat.