<prompt> Which of the following represents ventricular depolarization on ECG?PQPRQRSST  <response>: P wave which represents atrial depolarization.The QRS complex represents ventricular depolarization and the ST-T-U complex ST segment, T wave, and U wave represents ventricular repolarization.The J point is the junction between the end of the QRS complex and the beginning of the ST segment.Atrial repolarization ST and T is usually too low in amplitude to be detected, but it may become apparent in conditions such as acute pericarditis and atrial infarction. 