Final answer:
Osteocytes are the mature bone cells responsible for maintaining the bone tissue's metabolism and mineral concentration. They originate from osteoblasts and are replenished by osteoprogenitor stem cells.
Step-by-step explanation:
Osteocytes are mature bone cells, main cells in bone tissue, and maintain its daily metabolism. Osteocytes, once osteoblasts, become entrapped in their own secretions, which calcify and result in their becoming the primary cells of mature bone. They are found in small spaces called lacunae within the bone matrix. Osteocytes maintain the mineral concentration of the matrix through the secretion of enzymes and communicate through cytoplasmic processes that extend through canaliculi, channels within the bone tissue. Osteoclasts are another type of cell active in the breakdown of bone material for bone remodeling and releasing calcium into the bloodstream. The replenishment of osteoblasts and osteocytes, which cannot divide themselves, is made possible through these osteoprogenitor cells found in the periosteum and marrow.