Bone tissue. Coloured scanning electron micrograph (SEM) of cancellous (spongy) bone. Bone tissue can be either compact or cancellous. Cortical bone usually makes up the exterior of the bone, while cancellous bone is found in the interior. Cancellous bone is characterised by a honeycomb arrangement, comprising a network of trabeculae (rod-shaped tissue). These structures provide support and strength to the bone. The spaces within this tissue contain bone marrow, a blood forming substance. Magnification: x34 when printed at 10 centimetres wide.