Image by Professor P. Motta. This image is a false-color scanning electron micrograph (SEM) of normal human cancellous (spongy) bone. The shafts of long bones such as the femur are comprised of two types of bone of differing densities: compact bone forms the outer region, with the core formed by spongy or cancellous bone. In spongy bone the bony tissue is arranged as an open honeycomb.
Compact bone, from human femur. Bone is made up of two types of tissue: the compact bone forms a shell around the spongy cancellous bone that makes up the marrow space in the centre. Compact bone provides strength and rigidity and is solid in appearance. It is composed of a layered matrix of organic substances and inorganic salts that form around an intricate network of vasculature called Haversian canals. Credit: Ivor Mason, KCL, Wellcome Images.