Assertion: muscle fiber's myofibril | /r/HasProperty | actin
Facets:
value: basically
type: DEGREE
Source sentences:
text: Myofibrils are composed of long proteins including actin, myosin, and titin, and other proteins that hold them together.
text: The myofibrils are basically composed of two filamentous, contractile proteins, actin and myosin.