Final answer:
The osteon is the structural unit of compact bone, containing concentric lamellae around a central Haversian canal with blood vessels and nerves. Osteocytes in lacunae receive nutrients through canaliculi, illustrating the bone's intricate support system.
Step-by-step explanation:
The structural unit of compact bone is the osteon, also known as the Haversian system. Each osteon is composed of concentric lamellae, which are rings of calcified matrix. The laminated rings encircle the central canal, or Haversian canal, that houses blood vessels, nerves, and lymphatic vessels. These osteons are the fundamental functional units that provide strength and support to compact bone, allowing it to resist various stresses.
The lamellae are arranged around the central Haversian canal, forming a cylindrical structure. Osteocytes, which are mature bone cells, reside in small cavities called lacunae within the lamellae. Nutrition for the osteocytes is transported through tiny channels called canaliculi that connect the lacunae to the Haversian canal. This sophisticated network allows for nutrients and waste to be efficiently exchanged, maintaining the health of bone tissue.
Furthermore, Volkmann's canals run perpendicular to the Haversian canals, providing an avenue for the vascular and nerve supply from the periosteum and endosteum to reach each osteon. This integration of structure and function makes the osteon an exceptional example of the complex architecture found in compact bone tissue.