Final answer:
Lacunae are the small spaces in the bone where osteocytes are located, essential for maintaining bone tissue through networks that allow for nutrient and waste exchange.
Step-by-step explanation:
Small spaces in the bone where osteocytes are located are called lacunae (singular = lacuna). These lacunae are found at the borders of adjacent lamellae, which are concentric rings of calcified matrix within the structure known as an osteon, or Haversian system. Osteocytes maintain bone tissue via networks of long processes that stretch through tiny canals called canaliculi, facilitating the exchange of nutrients and wastes.
To understand the significance of lacunae within bone structure, it's crucial to consider the composition of bone, consisting of two types: compact and spongy (cancellous). Both kinds contain osteocytes housed in lacunae, but their arrangement differs. In spongy bone, lacunae and osteocytes form a lattice-like network inside matrix spikes called trabeculae. These trabeculae are designed to follow lines of stress, providing strength to the bone, while the spaces they create make the bone lighter and aid in the movement of muscles. Furthermore, these spaces in some spongy bones house red marrow where hematopoiesis takes place.
The Haversian canal, located centrally in each osteon, contains vital blood vessels, nerves, and lymphatic vessels. From the Haversian canal, these canals branch off to extend to the periosteum and endosteum through perforating canals also referred to as Volkmann's canals. This vascular structure ensures the maintenance of bone through the delivery of nutrients and removal of wastes, demonstrating the complex and dynamic nature of bone tissue.