The pericardium is which structure?

The pericardium is which structure?

• A. Double membrane sac that lines the outside of the heart
• B. Inner lining of the heart chambers
• C. Thick muscular layer
• D. Fatty tissue around

Answer: (A)

The pericardium is a protective double-layered sac that surrounds the heart. It consists of an outer fibrous layer and an inner serous layer that splits into a parietal part lining the sac and a visceral part (the epicardium) that covers the heart itself. The space between these serous layers, the pericardial cavity, contains a small amount of fluid to reduce friction as the heart beats. Because it forms a two-layered membrane around the outside of the heart, this description fits best. The inner lining of the heart chambers is the endocardium, the thick muscular layer is the myocardium, and the fatty tissue around is epicardial fat, not the pericardium.

The pericardium is a protective double-layered sac that surrounds the heart. It consists of an outer fibrous layer and an inner serous layer that splits into a parietal part lining the sac and a visceral part (the epicardium) that covers the heart itself. The space between these serous layers, the pericardial cavity, contains a small amount of fluid to reduce friction as the heart beats. Because it forms a two-layered membrane around the outside of the heart, this description fits best. The inner lining of the heart chambers is the endocardium, the thick muscular layer is the myocardium, and the fatty tissue around is epicardial fat, not the pericardium.