Biology - Body Fluids and Circulation Question with Solution | TestHub
P-wave of ECG indicates:
(A). Depolarization of atrial muscles
(B). Activation of SA node
(C). Spread of excitation from AV node to SA node
(D). Repolarization of atria and depolarization of ventricles
Choose thecorrectanswer from the options given below:
Options:
Answer:
Solution:
The P-wave in an electrocardiogram (ECG) represents the electrical excitation or depolarization of the atria, which leads to the contraction of both the atria.
Statement (A) is correct as it accurately describes the P-wave.
Statement (B) is incorrect because the activation of the SA node occurs just before the P-wave begins, but the P-wave itself represents the spread of this depolarization across the atrial muscles.
Statement (C) is incorrect because the excitation spreads from the SA node to the AV node, not the other way around.
Statement (D) is incorrect because the depolarization of the ventricles is represented by the QRS complex, and the repolarization of the atria is generally obscured by the QRS complex.
Therefore, only statement (A) is correct.
Answer: (A) is correct
