Which statement best describes lamellae in compact bone?

Which statement best describes lamellae in compact bone?

• A. They Are Composed of Osteocytes
• B. They Surround the Central Canal
• C. They Form Trabeculae
• D. They Are Found Only in Cartilage

Answer: (B)

Lamellae are the concentric layers of mineralized bone matrix that form around the central canal of an osteon in compact bone. They’re not themselves cells; osteocytes live within lacunae inside these layers and connect via canaliculi. The alternating orientation of collagen fibers from one lamella to the next gives bone greater strength, especially against twisting. This arrangement—lamellae surrounding the central canal—is the best description because it captures how compact bone is organized: the central canal runs through the middle, with lamellae wrapping around it to create the rigid, hollow cylinder of the osteon. The other options mischaracterize lamellae: they’re not made of osteocytes, they don’t form trabeculae (that’s a feature of spongy bone), and they aren’t found in cartilage.

Lamellae are the concentric layers of mineralized bone matrix that form around the central canal of an osteon in compact bone. They’re not themselves cells; osteocytes live within lacunae inside these layers and connect via canaliculi. The alternating orientation of collagen fibers from one lamella to the next gives bone greater strength, especially against twisting. This arrangement—lamellae surrounding the central canal—is the best description because it captures how compact bone is organized: the central canal runs through the middle, with lamellae wrapping around it to create the rigid, hollow cylinder of the osteon. The other options mischaracterize lamellae: they’re not made of osteocytes, they don’t form trabeculae (that’s a feature of spongy bone), and they aren’t found in cartilage.