EVERYDAY SCIENCE

Detailed explanation-1: -compact bone, also called cortical bone, dense bone in which the bony matrix is solidly filled with organic ground substance and inorganic salts, leaving only tiny spaces (lacunae) that contain the osteocytes, or bone cells.

Detailed explanation-2: -Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix. Between the rings of matrix, the bone cells (osteocytes) are located in spaces called lacunae.

Detailed explanation-3: -Compact bone: also known as cortical bone, this hard-outer layer is strong and dense. Cancellous bone: also known as trabecular bone, this spongy inner layer network of trabeculae is lighter and less dense than cortical bone.

Detailed explanation-4: -Like compact bone, spongy bone, also known as cancellous bone, contains osteocytes housed in lacunae, but they are not arranged in concentric circles. Instead, the lacunae and osteocytes are found in a lattice-like network of matrix spikes called trabeculae (singular = trabecula) (Figure 7).

Detailed explanation-5: -The central canal of an osteon contains the nerves and blood vessels that supply that area of bone. The central canal, also called the haversian canal, is an open space that runs through the middle of the osteon. Bone is living tissue, and it must have blood flow and nerves connected to it.