Time taken for electrical conduct from SA node to AV node in ECG is: (A) PR interval, (B) ST segment, (C) QT interval, (D) Cannot be determined by ECG
Answer is A. PR interval is the interval between beginning of p wave to the beginning of QRS. It indicates atrial depolarization and AV nodal delay. (REF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY)