The two layers of the pericardium produce and release serous fluid into the pericardial sac. Which of the following best describes these layers?

• A. Peritoneum
• B. Meninges
• C. Pleura
• D. Pericardium

Answer: (D)

Verified step by step guidance

1. Step 1: Begin by understanding the pericardium's role in the body. The pericardium is a double-layered membrane that surrounds the heart, providing protection and reducing friction during heartbeats.
2. Step 2: Learn about the two layers of the pericardium: the outer fibrous pericardium and the inner serous pericardium. The serous pericardium itself has two sublayers: the parietal layer (lining the fibrous pericardium) and the visceral layer (adhering directly to the heart).
3. Step 3: Understand the function of serous fluid. The serous fluid is secreted by the serous pericardium into the pericardial sac, which lies between the parietal and visceral layers. This fluid reduces friction as the heart contracts and relaxes.
4. Step 4: Compare the pericardium to other membranes mentioned in the options. The peritoneum lines the abdominal cavity, the meninges surround the brain and spinal cord, and the pleura surrounds the lungs. None of these are associated with the heart.
5. Step 5: Conclude that the correct answer is 'Pericardium,' as it is the membrane responsible for producing and releasing serous fluid into the pericardial sac surrounding the heart.