The diagram given here is the standard ECG of a normal person. The P-wave represents the:
Correct answer: C. Contraction of both the atria
- A. Beginning of the systole
- B. End of systole
- C. Contraction of both the atria
- D. Initiation of the ventricular contraction
Explanation
P-wave represents the electrical excitation (or depolarisation) of the atria, which leads to the contraction of both the atria. The QRS complex represents the depolarisation of the ventricles, which initiates the ventricular contraction. The contraction starts shortly after Q and marks the beginning of the systole. The T wave represents the return of the ventricles from excited to normal state. (repolarisation). The end of the T-wave marks the end of systole.
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