Which cells migrate to bone surfaces during remodeling to deposit bone matrix?

Which cells migrate to bone surfaces during remodeling to deposit bone matrix?

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

Answer: (D)

During bone remodeling, after the bone surface is prepared by resorption, new bone is formed by cells that migrate to the surface and lay down the matrix. These cells are osteoblasts. They synthesize osteoid, the organic component of bone matrix (primarily type I collagen and other proteins), which then mineralizes to become mature bone. Osteoblasts originate from mesenchymal stem cells on the bone surfaces and, as remodeling progresses, some become osteocytes embedded in the matrix or bone lining cells; others participate in ongoing deposition. Osteoclasts, in contrast, are the cells that resorb bone rather than deposit it. Chondroblasts produce cartilage, not bone, and osteocytes are mature bone cells embedded within the matrix rather than the cells actively laying down new matrix.

During bone remodeling, after the bone surface is prepared by resorption, new bone is formed by cells that migrate to the surface and lay down the matrix. These cells are osteoblasts. They synthesize osteoid, the organic component of bone matrix (primarily type I collagen and other proteins), which then mineralizes to become mature bone. Osteoblasts originate from mesenchymal stem cells on the bone surfaces and, as remodeling progresses, some become osteocytes embedded in the matrix or bone lining cells; others participate in ongoing deposition.

Osteoclasts, in contrast, are the cells that resorb bone rather than deposit it. Chondroblasts produce cartilage, not bone, and osteocytes are mature bone cells embedded within the matrix rather than the cells actively laying down new matrix.