Respuesta :

If you are talking about the pericardium sac it is a 2 layered fluid filled sac that surrounds the heart to protect it
 

Answer:

a sac around the heart that protects the heart and chest tissues

Explanation:

Pericardium

Pericardium: the protective saclike membrane enclosing the heart and its vessels

Gives protection

Reduces friction

Limits movement

Is found externally