The Innermost Layer of the Heart Wall is The

Question

The innermost layer of the heart wall is the
A)mediastinum.
B)parietal pericardium.
C)epicardium.
D)myocardium.
E)endocardium.

Accepted Answer

The innermost layer of the heart wall is the endocardium, which is a thin layer of endothelial cells that lines the chambers of the heart and the valves. The other options are not the innermost layer of the heart wall: the mediastinum is the space between the lungs where the heart is located, the parietal pericardium is the outer layer of the sac that surrounds the heart, the epicardium is the outermost layer of the heart wall, and the myocardium is the thick, muscular middle layer of the heart wall.