ANATOMY

Detailed explanation-1: -The myocardium contains a large number of mitochondria, providing energy for the heart muscle. The endocardium forms the inner lining of the heart, and the flaps which form the valves of the heart.

Detailed explanation-2: -Three layers of tissue form the heart wall. The outer layer of the heart wall is the epicardium, the middle layer is the myocardium, and the inner layer is the endocardium.

Detailed explanation-3: -The endocardium is the innermost layer of the heart. It lines the inner surfaces of the heart chambers, including the heart valves.

Detailed explanation-4: -Endocardial cells are specialized endothelial cells that, during embryogenesis, form a lining on the inside of the developing heart, which is maintained throughout life.

Detailed explanation-5: -Pericardium, or the layer surrounding the heart. Epicardium, the outside layer of the heart. Myocardium, the middle layer of the heart. Endocardium, the innermost layer of the heart.