Bicuspid valves are present at :

Options

A. Left atrioventricular junction
B. Right atrioventricular junction
C. At the base of pulmonary artery
D. At the base of aorta

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where bicuspid valves are located in the heart. Bicuspid valves are also known as mitral valves.

2. **Identifying the Bicuspid Valve**: The bicuspid valve is located between the left atrium and the left ventricle of the heart. This valve allows blood to flow from the left atrium into the left ventricle while preventing backflow.

3. **Analyzing the Options**:
- **Option 1**: Left atrioventricular junction - This is the correct answer as it is the location of the bicuspid (mitral) valve.
- **Option 2**: Right atrioventricular junction - This option is incorrect because the valve at this junction is the tricuspid valve, not the bicuspid valve.
- **Option 3**: Base of pulmonary artery - This option is incorrect as the valve present here is the pulmonary valve, not the bicuspid valve.
- **Option 4**: Base of aorta - This option is also incorrect because the valve at the base of the aorta is the aortic valve.

4. **Conclusion**: After analyzing all the options, the bicuspid valve is present at the left atrioventricular junction.

**Final Answer**: The bicuspid valves are present at the left atrioventricular junction.

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