Final answer:
The serous membranes surrounding the heart consist of the fibrous pericardium and the inner serous pericardium. The myocardium refers to the thick wall of the heart composed of cardiac muscle tissue.
Step-by-step explanation:
The serous membranes surrounding the heart consist of two layers: the fibrous pericardium and the inner serous pericardium. The fibrous pericardium is made of tough, dense connective tissue that protects the heart, while the inner serous pericardium consists of the parietal pericardium fused to the fibrous pericardium and the visceral pericardium (epicardium) fused to the heart. The serous pericardial cavity is filled with lubricating serous fluid that reduces friction as the heart contracts.
The myocardium refers to the thick wall of the heart composed mainly of cardiac muscle tissue. It is responsible for the contraction and pumping action of the heart. The myocardium is covered by the epicardium and the endocardium, which is a thin epithelial tissue.