Papillary muscles occur in

Options

A. Ventricles
B. Auricles
C. Atrioventricular valves
D. Pulmonary valves

Answer

**Step-by-Step Solution:**

1. **Understanding Papillary Muscles**: Papillary muscles are specialized muscles located within the ventricles of the heart. They play a crucial role in the functioning of the heart.

2. **Location**: These muscles are specifically found in the ventricles, which are the lower chambers of the heart responsible for pumping blood out to the lungs and the rest of the body.

3. **Function**: Papillary muscles are connected to the heart valves (specifically the atrioventricular valves, which include the mitral and tricuspid valves) via tendinous cords known as chordae tendineae.

4. **Role in Valve Function**: During ventricular contraction (systole), the papillary muscles contract, which helps to prevent the inversion (or prolapse) of the atrioventricular valves. This action ensures that blood flows in the correct direction and prevents backflow into the atria.

5. **Conclusion**: Therefore, papillary muscles occur in association with the atrioventricular valves of the heart, specifically in the ventricles.

**Final Answer**: Papillary muscles occur in the ventricles of the heart, associated with the atrioventricular valves (mitral and tricuspid valves).

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