In histology,<unk>  is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the<unk>  as several specific proteins. When the<unk>  becomes mineralized, it and the adjacent bone cells have developed into new bone tissue.<unk>  makes up about fifty percent of bone volume and forty percent of bone weight. It is composed of fibers and ground substance. The predominant type of fiber is type I collagen and comprises ninety percent of the<unk> . The ground substance is mostly made up of chondroitin sulfate and osteocalcin.
Osteoid
Osteon
Sesamoid bone
Favus
Ainhum
Keloid
Pectus
Osteotome