Learn about The Structure of Bones in this educational video from dizzo95.
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Male Speaker: This is the structure of a bone, spongy or cancellous bone forms the centre belt of all our bones. Its honey comb structure keeps the bones light, in contrast to the heavier compact bone, which gives it strength. Bone cells or osteocytes are contained in spaces called lacunae. The minute projections of bone cells trail into a joining channels known as canaliculi. Tissue fluid, which fills the lacunae allows the transfer of materials between bone cells and capillaries. Haversian systems each about 160 of an inch wide make up the structure of compact bone. Each system is formed by a series of rings called lamellae, which are deposits of mineral salts and collagen fibers. Haversian canals, which run through the centre of each Haversian system, contain the blood and the emphatic vessels supplying the bone. Here, arteries carrying oxygenated blood are shown in red. Veins carrying deoxygenated are shown in blue, with emphatic vessels are show in white. A section through the shaft of the femur along bone shows a central mass of spongy bone surrounded by the branching tubular Haversian systems. Blood vessels on the bone surface reach into the centre of each Haversian system supplying the bone cells.