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As soon as you come in! Define these words . Osteon Haversian Canal Lamella Osteocyte canaliculi. Microscopic Anatomy of the Bone. The Structural Unit of Compact Bone is called Osteon or Haversian System. Functional unit of the team.
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As soon as you come in!Define these words Osteon Haversian Canal Lamella Osteocyte canaliculi
Microscopic Anatomy of the Bone • The Structural Unit of Compact Bone is called • Osteon or Haversian System Functional unit of the team
Has concentric tubes of bone matrix called lamellae • surrounding a central canal that serves as a passageway for blood vessels and nerves.
Volkmann’s (perforating) canals lie at right angles to long axis • connect the blood and nerve supply of the periosteum to these central canals and medullary cavity.
Circumferential lamellae = just beneath the periosteum around the entire circumference of bone. • Interstitial Lamellae = lie between intact osteons filling the space in between
Spongy bones lacks osteons, but has trabeculae that align along lines of stress.
Bone Composition • Organic: • A. osteogenic, osteoblasts, osteocytes, osteoblast -- all cell types • B. Osteoid -- ~1/3 of matrix including ground substance and collagen fibers • Resilent and great tensile strength “sacrificial bonds” dissipate energy thus preventing fractures
Inorganic: ~65% by mass of inorganic salts. Mainly calcium phosphate crystals. This accounts for the hardness of bones which resists compression. Drink your milk!!
This mix of collagen, proteins, and minerals makes bone durable and strong. • ½ as strong as steel at resisting compression and just as strong as resisting tension. • And obviously bones remain long after death, leaving remains that allow us to study humans from the past