cells that synthesize the organic components of the bone matrix are called
1 Osteoblasts. 2  Cells that are derived from osteoprogenitor cells and are responsible for the synthesis of the organic components of bone matrix, which is called osteoid. 3  They are located on the surface of bone tissue and resemble epithelium. Endosteum: Thin layer of osteoprogenitor cells, osteoblasts and a small amount of connective tissue that lines all internal surfaces of cavities within bone including the osteonic canals and marrow spaces. 2  Bone Matrix. 3  Mature bone is made up of approximately 70% inorganic salts and 30% organic matrix by weight.