Assertion: endocardium's layer | /r/CapableOf | lubricate the heart
Facets:
value: to prevent friction
type: PURPOSE
Source sentences:
text: , this structure contains two layers that lubricate the heart to prevent friction from occurring during heart activity.
text: : Located deeper than the fibrous pericardium, this structure contains two layers that lubricate the heart to prevent friction from occurring during heart activity.