describe the two layers of the pericardium. what is the function of pericardial fluid
Surrounding the heart is a fibrous sac called the pericardium. This sac protects the heart, and is actually composed of two layers: an inner visceral one and an outer parietal one. When the heart moves (i.e. when the heart beats), these two layers move with it.For this to happen, it is important that there is no friction between the two layers of the pericardium, which is why pericardial fluid lines the inner space between the them.Much like oil in an engine, the pericardial fluid makes for less friction between the inner and outer layer of the pericardium.he pericardial cavity or sac is the potential space between the parietal and visceral layers of serous pericardium. In other words, two different layers of cardiac tissue.