An atrioventricular valve prevents the back flow or leakage of blood from-

Options

A. The right ventricle into the right atrium
B. The left atrium into the left ventricle
C. The aorta into the left ventricle
D. The pulmonary vein into the right atrium

Answer

**Step-by-Step Solution:**

1. **Understanding Atrioventricular Valves**: The atrioventricular (AV) valves consist of two main valves: the tricuspid valve (located between the right atrium and right ventricle) and the bicuspid (or mitral) valve (located between the left atrium and left ventricle).

2. **Function of AV Valves**: The primary function of the AV valves is to prevent the backflow of blood from the ventricles to the atria during ventricular contraction (systole). This ensures that blood flows in a unidirectional manner from the atria to the ventricles.

3. **Location of Blood Flow**: During the cardiac cycle, blood flows from the atria (upper chambers) into the ventricles (lower chambers). When the ventricles contract, the AV valves close to prevent blood from flowing back into the atria.

4. **Identifying the Correct Answer**: The question asks where the AV valves prevent backflow. The correct answer is that the AV valves prevent the backflow of blood from the right ventricle into the right atrium. This is specifically the function of the tricuspid valve.

5. **Conclusion**: Therefore, the atrioventricular valve prevents the backflow or leakage of blood from the right ventricle into the right atrium.

**Final Answer**: The atrioventricular valve prevents the backflow of blood from the right ventricle into the right atrium.

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