Final answer:
The extracellular material of the connective tissue is called the extracellular matrix, which is made of protein fibers embedded in protein-polysaccharide molecules called proteoglycans. Collagen is the main protein in connective tissue.
Step-by-step explanation:
Connective tissues, such as bone and blood, are made up of cells that are separated by non-living material called the extracellular matrix. The extracellular matrix is made of protein fibers embedded in an amorphous mixture of protein-polysaccharide molecules called proteoglycans. The most abundant protein in connective tissue is collagen.