MCQ IN MEDICINE

Detailed explanation-1: -The muscles of the heart, termed the myocardium, make up the middle and thickest layer of the heart wall. This layer lies between the single-cell endocardium layer, which lines the inner chambers, and the outer epicardium, which makes up part of the pericardium that surrounds and protects the heart.

Detailed explanation-2: -The epicardium is the outer layer that contains blood vessels. 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.