What histologic feature defines a central passage in an osteon?

What histologic feature defines a central passage in an osteon?

• A. Central Haversian Canal With Lamellae And Osteocytes In Lacunae
• B. Lacunae Without Lamellae
• C. Blood Vessel-Free Channel
• D. Periosteal Strands Surrounding a Canal

Answer: (A)

The central passage in an osteon is the Haversian canal—the central, vascular channel that runs through the core of each osteon. Its defining feature is the surrounding concentric lamellae of compact bone, with osteocytes housed in lacunae between those lamellae and connected by canaliculi. This arrangement forms the Haversian system, providing a route for nutrients and blood vessels to reach osteocytes embedded within the lamellar bone. The periosteal layer forms the outer covering, not the central passage, and a channel without a vascular supply or lacunae without lamellae does not describe the organized osteon structure.

The central passage in an osteon is the Haversian canal—the central, vascular channel that runs through the core of each osteon. Its defining feature is the surrounding concentric lamellae of compact bone, with osteocytes housed in lacunae between those lamellae and connected by canaliculi. This arrangement forms the Haversian system, providing a route for nutrients and blood vessels to reach osteocytes embedded within the lamellar bone. The periosteal layer forms the outer covering, not the central passage, and a channel without a vascular supply or lacunae without lamellae does not describe the organized osteon structure.