Question

The pericardial sac that encloses the heart is a two-layered structure. The outer layer is the ________.

Answer 1

The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made of serousmembrane (serous pericardium).