GENERAL HISTOLOGY

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: 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-3: -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).