MICROANATOMY

Detailed explanation-1: -The walls of the heart are composed of three layers: Epicardium-the outer layer. Myocardium-the middle, muscular layer. Endocardium-the inner layer.

Detailed explanation-2: -The myocardium is the middle muscular layer of the heart. It is the thickest layer which lies between the single-cell endocardium layer, and the outer epicardium, which makes up the visceral pericardium that surrounds and protects the heart. The myocardium is composed of specialized muscle cells called cardiomyocytes.

Detailed explanation-3: -The wall of the heart separates into the following layers: epicardium, myocardium, and endocardium. These three layers of the heart are embryologically equivalent to the three layers of blood vessels: tunica adventitia, tunica media, and tunica intima, respectively.

Detailed explanation-4: -The myocardium is the middle layer that is composed of contractile tissues. The endocardium is the innermost layer and composes the valves, inner lining of the chambers, and contains vessels and nerves.

Detailed explanation-5: -The pericardium is the fibrous sac that surrounds the heart. It can be divided into three layers, the fibrous pericardium, the parietal pericardium, and the visceral pericardium. The parietal and visceral pericardia together form the serous pericardium.