Assertion: collagen | /r/AtLocation | cartilage
Facets:
Source sentences:
text: Collagen is a natural protein found in bone, cartilage, skin, and tendons; there are 27 different types of naturally occurring collagens in the body.
text: It is found in many tissues such as skin, tendons, ligaments, cartilage and
text: Collagen can also be found in the skin, cornea, blood vessels, cartilage, digestive tract, and intervertebral disc.