Where are osteocytes located in mature bone?

• A. In lacunae within mineralized matrix
• B. In the central canal
• C. On the bone surface lining endosteum
• D. In the periosteum

Answer: (A)

Osteocytes are mature bone cells embedded within the mineralized bone matrix. They sit in small spaces called lacunae that are nestled between the lamellae of the tissue. Each osteocyte sends out long processes through tiny channels called canaliculi, connecting with neighboring osteocytes and with cells on the bone surface via gap junctions. This positioning—inside lacunae in mineralized matrix—explains their role in sensing strain and coordinating remodeling. The central canal houses blood vessels and nerves, not osteocytes; the periosteum lines the outer surface, and the endosteum lines internal surfaces.