Question

Choose the incorrect statement.

• A. The end of P-wave marks the end of the systole
• B. The ventricular contraction starts shortly after Q and marks the beginning of the systole
• C. The number of QRS complexes per unit time period determine the heart rate of an individual
• D. The end of T-waves mark the end of systole

Answer 1

The correct option is A The end of P-wave marks the end of the systole

An electrocardiogram — EKG or ECG — is a graphical representation of the electrical activity of the heart measured across a cardiac cycle. During every heart beat, an electrical impulse (or “wave”) travels through the heart.

It is marked by three entities – a P-wave, a QRS complex and a T-wave – each has a fairly unique pattern.

The P-wave represents atrial depolarisation. The QRS complex represents ventricular depolarisation. The T-wave represents ventricular repolarisation.

The P-wave which represents the electrical depolarisation of the atria only and leads to the atrial systole (contraction of both the atria). All systolic phases (atrial and ventricular) are completed only by the end of P and QRS waves combined.