Question

The diagram given here is the standard ECG of a normal person. The P wave represents the

A. Contraction of both the arteries.
B. Initiation of ventricular contraction
C. Beginning of the systole
D. End of systole

Answer 1

An electrocardiogram or ECG is a test that can be used to check the heart's rhythm and its electrical activity. The sensors will be attached to the skin which is used to detect the electrical signals produced by the heart each time it beats. ECG consists of waveform components that indicate electrical events during one heartbeat. The waveforms are labelled as P, Q, R, S, T and U.

Complete answer:
Option A Contraction of both the arteries: P wave is the initial short upward movement of the ECG that indicates the atria are contracting and pumping blood into the ventricles. This option is correct.
Option A is correct.
Option B initiation of ventricular contraction: In electrocardiogram, the QRS complex denotes the depolarisation of the ventricles which initiates the ventricular contraction.
Option B is incorrect.
Option C Beginning of systole: The systole is the part of the cardiac cycle during which the chambers of the heart muscle contract after refilling with blood. In an electrocardiogram the beginning of systole is marked by the deflections of the QRS complex.
Option C is incorrect.
Option D End of systole: End of systole denotes the volume of blood that remains in the ventricle after contraction. In electrocardiogram the end systolic volume will be seen at the end of T wave.
Option D is incorrect.

Option A Contraction of both the arteries is the correct answer.

Note:
ECG is usually done to detect any abnormalities in the heart. ECG can detect abnormal heart rhythms, blocked or narrowed arteries, heart attack, arterial wall disease, pulmonary embolism etc. A person should get ECG if he/she experiences shortness of breath, murmurs, fainting and seizures. ECGs can be recorded as short intermittent monitoring or continuous ECG monitoring.