Which bone cell resides in lacunae within the bone matrix?

Which bone cell resides in lacunae within the bone matrix?

• A. Osteoblasts
• B. Osteoclasts
• C. Osteocytes
• D. Fibroblast

Answer: (C)

Osteocytes are mature bone cells that reside within lacunae—tiny spaces carved into the mineralized bone matrix. They originate when an osteoblast becomes embedded in its own secreted matrix during bone formation and then differentiate into an osteocyte. Once trapped in this matrix, osteocytes stay inside lacunae and extend slender processes through canaliculi to communicate with neighboring cells and help regulate mineral balance. This is different from osteoblasts, which stay on the bone surface to build new matrix, and osteoclasts, which resorb bone from the surface. Fibroblasts are connective-tissue cells found outside the bone matrix. So, the cell living inside lacunae in the bone matrix is the osteocyte.

Osteocytes are mature bone cells that reside within lacunae—tiny spaces carved into the mineralized bone matrix. They originate when an osteoblast becomes embedded in its own secreted matrix during bone formation and then differentiate into an osteocyte. Once trapped in this matrix, osteocytes stay inside lacunae and extend slender processes through canaliculi to communicate with neighboring cells and help regulate mineral balance. This is different from osteoblasts, which stay on the bone surface to build new matrix, and osteoclasts, which resorb bone from the surface. Fibroblasts are connective-tissue cells found outside the bone matrix. So, the cell living inside lacunae in the bone matrix is the osteocyte.