Which cell type is NOT one of the main bone cells?

Which cell type is NOT one of the main bone cells?

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

Answer: (D)

The key idea is distinguishing bone cells from cartilage cells. In bone tissue, the three main cell types involved in formation, maintenance, and remodeling are osteoblasts, which build new bone; osteocytes, which are mature bone cells embedded in the bone matrix and serve as strain sensors that coordinate remodeling; and osteoclasts, which resorb bone during turnover. Chondrocytes are cartilage cells responsible for creating and maintaining cartilage matrix. They reside in cartilage, not bone, and do not serve as primary bone-maintaining cells in mature bone tissue. So, identifying the cell type that is not a main bone cell points to chondrocytes, the cartilage cells.

The key idea is distinguishing bone cells from cartilage cells. In bone tissue, the three main cell types involved in formation, maintenance, and remodeling are osteoblasts, which build new bone; osteocytes, which are mature bone cells embedded in the bone matrix and serve as strain sensors that coordinate remodeling; and osteoclasts, which resorb bone during turnover. Chondrocytes are cartilage cells responsible for creating and maintaining cartilage matrix. They reside in cartilage, not bone, and do not serve as primary bone-maintaining cells in mature bone tissue. So, identifying the cell type that is not a main bone cell points to chondrocytes, the cartilage cells.