Assertion: bone marrow's cell | /r/CapableOf | serve as matrix
Facets:
Source sentences:
text: Another method classified tissues into four broad groups according to cell composition: epithelial tissues, composed of cells that make up the body’s outer covering and the membranous covering of internal organs, cavities, and canals; endothelial tissues, composed of cells that line the inside of organs; stroma tissues, composed of cells that serve as a matrix in which the other cells are embedded; and connective tissues, a rather amorphous category composed of cells and an extracellular matrix that serve as a connection from one tissue to another.