Question

The heart is enclosed in a double layered sack called​

Answer 1

Answer:

pericardium

The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. The pericardial sac has two layers, a serous layer and a fibrous layer. It encloses the pericardial cavity which contains pericardial fluid.

Answer 2

Answer:

pericardium

The heart is enclosed within a double-walled sac called the pericardium.