Question

The QRS complex in a standard ECG represents:

Answer 1

Correct option is B. Depolarisation of ventricles

An ECG shows consecutive waves: P, QRS complex, and T.

• The P wave represents the depolarization of atria and leads to contraction of both atria.
• The QRS complex represents the depolarization of ventricles which leads to the initiation of ventricular contraction.
• T wave represents the return of ventricles from excited to the normal state (repolarisation of ventricles).

So, the correct answer is 'Depolarisation of ventricles'.