ECG depicts the depolarisation and repolarisation processes during the cardiac cycle. In the ECG of a normal healthy individual one of the following waves is not represented.
Depolarisation of atria
Repolarisation of atria
Depolarisation of ventricles
Repolarisation of ventricles
The correct option is D Repolarisation of atria
ECG that is electrocardiogram is the wave diagram that represents the travel of action potential in the heart chambers.
The wave of ECG for a normal heart is made up of PQRST.
The wave P is representation the depolarization the atrial muscles as the muscles of the atria enter a state of excitation after receveing an stimulus.
The wave QRS is the longest wave in EGC this wave represents the depolarization of the ventricles and along with depolarization of the ventricle repolarization of the atria also takes place but it is not represented by any wave in the ECG.
The last wave that is the T way is representing the repolarization of the ventricles as they come down from their excited state to the normal state.
Therefore the answer is "Repolarisation of atria" correct.