Duration of Auricular diastole is

Options

A. 0.7 sec
B. 0.5 sec
C. 0.9 sec
D. 1.5 sec

Answer

To determine the duration of auricular diastole, we will analyze the cardiac cycle and its components step by step.

### Step-by-Step Solution:

1. **Understanding the Cardiac Cycle**:
- The cardiac cycle consists of a series of events that occur during one heartbeat. It includes both contraction (systole) and relaxation (diastole) phases of the heart chambers (atria and ventricles).

2. **Duration of the Cardiac Cycle**:
- The entire cardiac cycle lasts approximately 0.8 seconds in a normal resting adult.

3. **Components of the Cardiac Cycle**:
- The cardiac cycle includes:
- Atrial systole (contraction of the atria)
- Atrial diastole (relaxation of the atria)
- Ventricular systole (contraction of the ventricles)
- Ventricular diastole (relaxation of the ventricles)

4. **Duration of Atrial Diastole**:
- Atrial diastole occurs when the atria are relaxed and filling with blood.
- In a typical cardiac cycle, the duration of atrial diastole is approximately 0.7 seconds.

5. **Evaluating the Options**:
- Given options for the duration of auricular diastole are:
- Option 1: 0.7 seconds
- Option 2: 0.5 seconds
- Option 3: 0.9 seconds
- Option 4: 0.5 seconds
- From our analysis, the correct duration of auricular diastole is 0.7 seconds, which corresponds to Option 1.

6. **Conclusion**:
- Therefore, the correct answer is **0.7 seconds**.