In a standard ECG which one of the following alphabets is the correct ...
In a standard ECG, the P wave is a small upward wave that represents depolarisation of atria which leads to contraction of both atria.
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In a standard ECG which one of the following alphabets is the correct ...
The Correct Answer is Option 'C': P - depolarisation of the atria.
Explanation:
An electrocardiogram (ECG) is a medical test that measures the electrical activity of the heart. It is a commonly used tool to diagnose and monitor various heart conditions. The ECG waveform consists of several distinct deflections or waves, each representing a specific event in the cardiac cycle.
The correct representation of the respective activity of the human heart in a standard ECG is as follows:
P wave: Depolarization of the Atria
The P wave represents the depolarization (contraction) of the atria. It is a small, upward deflection in the ECG waveform. The electrical signal starts in the sinoatrial (SA) node, the natural pacemaker of the heart, and spreads through the atria, causing them to contract and pump blood into the ventricles.
QRS complex: Depolarization of the Ventricles
The QRS complex represents the depolarization (contraction) of the ventricles. It consists of three deflections: Q, R, and S waves. The Q wave is the first downward deflection, the R wave is the first upward deflection, and the S wave is the downward deflection following the R wave. The QRS complex indicates the initiation of ventricular contraction and the pumping of blood to the rest of the body.
T wave: Repolarization of the Ventricles
The T wave represents the repolarization (relaxation) of the ventricles. It is a small, upward deflection following the QRS complex. During this phase, the ventricles are preparing for the next cardiac cycle. The T wave is important in assessing the electrical health of the heart and can provide information about potential abnormalities.
S wave: Start of Systole
The S wave is not directly associated with the activities of the human heart as mentioned in the options. It is a downward deflection following the R wave in the QRS complex. The S wave represents the depolarization of the last portion of the ventricles.
Therefore, the correct representation of the respective activity of the human heart in a standard ECG is the 'P wave' for depolarization of the atria.
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