Which of the following waves of an ECG pattern is correctly described? Pwave-depolarization of atria B. QRS complex-repolarization of ventricles Twave-depolarization of ventricles D. All of these are correct Moving to another question will save this response
The Correct Answer and Explanation is :
The correct answer is A. P wave – depolarization of atria.
Explanation:
An ECG (electrocardiogram) is a recording of the electrical activity of the heart. It is made up of several waves, each corresponding to a specific electrical event that occurs in the heart during a heartbeat.
- P wave: This represents the depolarization of the atria.
- Depolarization is the process by which the electrical charge inside the cells of the atria changes, leading to contraction. The P wave is the first deflection in an ECG trace and is typically small and upward. It reflects the electrical impulse as it travels through the atria from the sinoatrial (SA) node to the atrioventricular (AV) node.
- QRS complex: This wave corresponds to the depolarization of the ventricles.
- The QRS complex is usually the largest and most noticeable wave on an ECG. It represents the electrical impulse traveling through the ventricles, leading to their contraction. The Q wave is the initial downward deflection, the R wave is the sharp upward deflection, and the S wave is a downward deflection that follows the R wave. This complex indicates the rapid spread of electrical activity through the ventricles and is critical for efficient pumping of blood from the heart.
- T wave: This represents the repolarization of the ventricles.
- Repolarization is the process by which the heart muscle cells reset their electrical state after contraction, allowing them to prepare for the next heartbeat. The T wave is typically a broad, upward wave following the QRS complex. It shows the recovery phase of the ventricles after they contract.
Thus, the only correct statement in the options is A. P wave – depolarization of atria, because the other choices contain incorrect descriptions of the wave functions. The QRS complex deals with depolarization of the ventricles, and the T wave corresponds to repolarization, not depolarization.