ESS 205 Anatomy and Physiology Lecture 10Outline of Last Lecture I. Bone TissueII. Functions of Bony SkeletonIII. Structure of flat boneIV. Structure of long boneOutline of Current LectureV. Structure of Compact Bonea. PartsVI. Histology of Spongy boneVII. Cells of Osseous TissueVIII. Matrix of Osseous TissueIX. Bone DisordersCurrent Lecture1. Compact bone is made up of a bunch of osteons. *Not every osteons runs the complete length of the bone. Many times they are stacked on top of each other*. There are five parts to compact bone. The first is Haversian (central) canal. It is a canal where blood and nerve vessels pass. The next is the Perforating (Volkman) Canal. It crosses the matrixand feeds into the central canal. Third are Canaliculi. It is a channel that provides nourishment and connects osteocytes (bone cells.) Lacuna is a cavity that the osteocytesgroup in. Lamellae are concentric rings that surround Lacunae. 2. The first cell that makes up osseous tissue is called the osteogenic cell. It resides in endosteum, periosteum, or central canals. It arises from fibroblasts and is the only source for new osteoblasts. They multiply continuously and turn into amitotic osteoblastThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.in response to stress and fractures. Osteoblasts form and help mineralize organic matter of matrix. Osteocytes are former osteoblasts that have become trapped in matrix they formed. Lacunae are connected by gap junctions and they signal mechanical stress. Osteoclasts develop in bone marrow by fusion of 3-50 of same stem cells that give rise to monocytes found in blood. They reside in resorption bays. Bones are constantly remodeling. It is a delicate balance of osteoblastic and osteoclastic activity based on needs of the body.3. The matrix of the osseous tissue is a third organic and two thirds inorganic. The organic matter consists of collagen, glycosaminoglycans, proteoglycans, and glycoproteins. The inorganic matter is 85% hydroxyapatite and 10% calcium carbonate. The combination provides strength and resilience. The minerals resist compression and the collagen resists tension. The bone adapts to tension and compression by varying proportions of minerals and collagen fibers. 4. Bone Disorders. Osteomalcia is inadequate mineralization that causes bone softening and deformation. Rickets is where the epiphyseal plates do not ossify. It causes dwarfismand deformation. Myositis Ossificans stems from severe hematoma incorrectly treated. It causes depositing of bone into muscles. Osteoporosis is the most common bone disease. When the bone loses mass it causes brittleness in the