Light micrograph of a section through the interior of a bone showing cancellous, or spongy, bone tissue. Cancellous bone is characterised by a honeycomb arrangement, comprising a network of trabeculae of light porous bone (pink). Within the bone are osteocytes (purple), which sense mechanical stress and are involved in bone remodelling. The spaces between the trabeculae contain bone marrow (white and purple), a blood forming substance. Magnification: x400 when printed at 15cm tall.