Here are the essential concepts you must grasp in order to answer the question correctly.
Pericardium
The pericardium is a double-walled sac that encloses the heart, providing protection and anchoring it within the thoracic cavity. It consists of two main layers: the fibrous pericardium, which is a tough outer layer, and the serous pericardium, which is a thinner inner layer that produces serous fluid to reduce friction during heartbeats.
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Fibrous Pericardium
The fibrous pericardium is the outermost layer of the pericardium, composed of dense connective tissue. It serves to protect the heart, limit its motion, and prevent overexpansion. This layer is firmly attached to the diaphragm and the great vessels, providing structural support and stability to the heart.
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Serous Pericardium
The serous pericardium is the inner layer of the pericardium, consisting of two parts: the parietal layer, which lines the fibrous pericardium, and the visceral layer, which adheres directly to the heart's surface. This layer secretes serous fluid, which lubricates the heart and reduces friction as it beats, facilitating smooth cardiac movement.
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