In electrocardiography P-Q interval represents :

Options

A. Atrial depolarization
B. Ventricular depolarization
C. Conduction time through atria , A.V node and rest of conducting tissue
D. Ventricular repolarization

Answer

To solve the question regarding what the P-Q interval represents in electrocardiography (ECG), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Components of the ECG**:
- The ECG is a graphical representation of the electrical activity of the heart during a cardiac cycle. It consists of several waves: P wave, QRS complex, and T wave.

2. **Identify the Waves**:
- **P Wave**: Represents atrial depolarization (the electrical activation of the atria).
- **QRS Complex**: Represents ventricular depolarization (the electrical activation of the ventricles).
- **T Wave**: Represents ventricular repolarization (the return of the ventricles to their resting state).

3. **Define the P-Q Interval**:
- The P-Q interval (also known as the P-R interval) is the time between the onset of the P wave and the onset of the QRS complex. It reflects the time taken for the electrical impulse to travel from the atria to the ventricles.

4. **Analyze the Options**:
- The options provided include:
- Atrial depolarization
- Ventricular depolarization
- Conduction time through atria, AV node, and rest of conducting tissue
- Ventricular repolarization
- From our understanding, the P-Q interval does not represent atrial depolarization (which is the P wave), nor does it represent ventricular depolarization (which is the QRS complex), or ventricular repolarization (which is the T wave).

5. **Conclusion**:
- The P-Q interval specifically represents the conduction time through the atria, AV node, and the rest of the conducting tissue. Therefore, the correct answer is that the P-Q interval represents the conduction time through the atria, AV node, and the rest of the conducting tissue.

### Final Answer:
The P-Q interval represents the conduction time through the atria, AV node, and the rest of the conducting tissue.

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