 Section 1 of Grey's Anatomy, Part 2. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org. Recorded by Laurie Ann Walden. Anatomy of the Human Body, Part 2, by Henry Gray. Sin Dismology, Introduction. The bones of the skeleton are joined to one another at different parts of their surfaces, and such connections are termed joints or articulations. Where the joints are immovable, as in the articulations between practically all the bones of the skull, the adjacent margins of the bones are almost in contact, being separated merely by a thin layer of fibrous membrane named the sutral ligament. In certain regions at the base of the skull, this fibrous membrane is replaced by a layer of cartilage. Where slight movement combined with great strength is required, the osseous surfaces are united by tough and elastic fibrocartilages, as in the joints between the vertebral bodies and in the inter pubic articulation. In the freely movable joints, the surfaces are completely separated. The bones forming the articulation are expanded for greater convenience of mutual connection, covered by cartilage and enveloped by capsules of fibrous tissue. The cells lining the interior of the fibrous capsule form an imperfect membrane, the synovial membrane, which secretes a lubricating fluid. The joints are strengthened by strong fibrous bands called ligaments, which extend between the bones forming the joint. Bone. Bone constitutes the fundamental element of all the joints. In the long bones, the extremities are the parts which form the articulations. They are generally somewhat enlarged and consist of spongy, cancelous tissue with a thin coating of compact substance. In the flat bones, the articulations usually take place at the edges, and in the short bones at various parts of their surfaces. The layer of compact bone which forms the joint surface and to which the articular cartilage is attached is called the articular lamella. It differs from ordinary bone tissue in that it contains no heversian canals and its lacunae are larger and have no canaliculi. The vessels of the cancelous tissue as they approach the articular lamella turn back in loops and do not perforate it. This layer is consequently denser and firmer than ordinary bone and is evidently designed to form an unyielding support for the articular cartilage. Cartilage. Cartilage is a non-vascular structure which is found in various parts of the body. In adult life, chiefly in the joints, in the parietes of the thorax, and in various tubes such as the trachea and bronchi, nose and ears. All complete. Ready to continue?