Final answer:
The wave with the highest amplitude on a normal electrocardiogram is the R-wave, part of the QRS complex, which represents ventricular depolarization.
Step-by-step explanation:
In a normal electrocardiogram (ECG or EKG), the wave with the highest amplitude is the R-wave, which is part of the QRS complex. The P wave represents atrial depolarization, which is when the atria contract to pump blood into the ventricles. However, the QRS complex, and specifically the R-wave within that complex, indicates ventricular depolarization, which involves a much stronger electrical signal due to the larger muscle mass of the ventricles. This depolarization causes the ventricles to contract and pump blood to the lungs and body. Lastly, the T wave represents the repolarization of the ventricles. The repolarization of the atria occurs during the QRS complex and is consequently masked on the ECG.