Final answer:
The QRS complex arises from ventricular depolarization, representing the electrical activity of the ventricles during the cardiac cycle.
Step-by-step explanation:
The QRS complex arises from ventricular depolarization. It represents the electrical activity of the ventricles during the cardiac cycle. The QRS complex is a result of the depolarization of the ventricular muscle, leading to ventricular contraction.
Ventricular depolarization is a phase in the cardiac cycle during which the ventricles of the heart undergo an electrical activation that leads to contraction. This process is a key component of the heart's rhythm, allowing it to efficiently pump blood throughout the body.