GENERAL HISTOLOGY

Detailed explanation-1: -Spongy (cancellous) bone is lighter and less dense than compact bone. Spongy bone consists of plates (trabeculae ) and bars of bone adjacent to small, irregular cavities that contain red bone marrow. The canaliculi connect to the adjacent cavities, instead of a central haversian canal, to receive their blood supply.

Detailed explanation-2: -Compact Bone It can be found under the periosteum and in the diaphyses of long bones, where it provides support and protection. The microscopic structural unit of compact bone is called an osteon, or Haversian system. Each osteon is composed of concentric rings of calcified matrix called lamellae (singular = lamella).

Detailed explanation-3: -Spongy bone is commonly found at the end of long bones, as well as the ribs, skull, pelvic bones and vertebrae. Located in the spaces, between the trabeculae of some spongy bones is red bone marrow. Blood vessels within red bone marrow supply osteocytes of spongy bone and aid in removing waste products.