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Haversian System. http://webs.ashlandctc.org/mflath/KEY%20SKELETAL%20I%20OBJECTIVES.htm. Clopton Harvers. Born in 1655 in England Studied at Cambridge Both a Physician and an Anatomist Practiced medicine in London for most of his life
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Haversian System http://webs.ashlandctc.org/mflath/KEY%20SKELETAL%20I%20OBJECTIVES.htm
Clopton Harvers • Born in 1655 in England • Studied at Cambridge • Both a Physician and an Anatomist • Practiced medicine in London for most of his life • Credited for his in-depth studies of the bones that ultimately led to the discovery of the 'Haversian canals' in them • Died in 1702
What exactly is a Harversian System? • Compact bone contains many cylinder-shaped structural units called osteons (Haversian systems) • Each osteon runs lengthwise through the bone • These Haversian systems makeup the structural framework of compact bone • The unique composition of the osteons allows for the delivery of nutrients and the removal of certain waste products produced from metabolically active bone cells
Composition of the Haversian System • Four types of structures make up each osteon (haversian system) • 1. Lamellae • 2. Lacunae • 3. Canaliculi • 4. Haversian Canal
Lamellae (la-MEL-ay) • Concentric, cylinder-shaped layers of calcified matrix http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Lacunae (la-KYOO-nay) • Latin for “little lakes” • Small spaces containing tissue fluid in which bone cells lie imprisoned between the hard layers of the lamellae http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Canaliculi (CAN-uh-LIK-you-lye) • Very tiny canals radiating in all directions from the lacunae and connecting them to each other and into the Haversian canal http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Haversian Canal • Extends lengthwise through the center of each osteon • Contains blood vessels, lymphatic vessels, and nerves from the Haversian canal • Nutrients and oxygen move through canalculi to the lacunae and their bone cells • Each Haversian canal is connected by tansverse Volkmann’s canals (contain nerves and vessels that carry blood and lymph to the osteons) http://newscenter.lbl.gov/feature-stories/2008/08/06/the-toughness-of-bone/