Which statement is true regarding osteoblasts?

Which statement is true regarding osteoblasts?

• A. They resorb bone matrix
• B. They produce bone matrix
• C. They differentiate into osteoclasts
• D. They reside only in cartilage

Answer: (B)

Osteoblasts are the bone-forming cells responsible for producing the bone matrix. They synthesize and secrete the organic component of the matrix (osteoid), mainly type I collagen and various non-collagenous proteins, and they initiate mineralization to form new bone. These cells originate from mesenchymal stem cells in the periosteum and endosteum and line active bone surfaces. As bone formation proceeds, some osteoblasts become embedded in the matrix to become osteocytes, or remain on surfaces as bone-lining cells; they do not resorb bone. Resorption is carried out by osteoclasts, which come from a different lineage. Also, osteoblasts do not reside only in cartilage; cartilage contains chondroblasts and chondrocytes, whereas osteoblasts function in bone-forming sites.

Osteoblasts are the bone-forming cells responsible for producing the bone matrix. They synthesize and secrete the organic component of the matrix (osteoid), mainly type I collagen and various non-collagenous proteins, and they initiate mineralization to form new bone. These cells originate from mesenchymal stem cells in the periosteum and endosteum and line active bone surfaces. As bone formation proceeds, some osteoblasts become embedded in the matrix to become osteocytes, or remain on surfaces as bone-lining cells; they do not resorb bone. Resorption is carried out by osteoclasts, which come from a different lineage. Also, osteoblasts do not reside only in cartilage; cartilage contains chondroblasts and chondrocytes, whereas osteoblasts function in bone-forming sites.