1. To do list for today functions of the skeleton bone shapes general features of bone – parts bone histology = cells + matrix Vitamin D, calcium & bones structural disorders of bone osteoporosis

2. long shortflatirregular

3. Fig. 6.2a(TE Art) Epiphysis Diaphysis Spongy bone Epiphyseal line Compact bone Medullary cavity Endosteum Articular cartilage Periosteum Articular cartilage osteo = bone peri = around endo = within artic = joint

4. Compact bone Spongy Bone (diploe) Suture Flat bones

5. Bone tissue = bone cells = matrix

6. periosteum endosteum osteon Central canal trabeculae Perforating canal Perforating fibers Compact bone Spongy bone Bone marrow

7. Osteoprogenitor ** osteocyte ** ** Osteoblast ** Bone cells canaliculi

8. Stem cells osteoclast Bone dissolving macrophages ** Osteoclast ** Why dissolve bone?? Paget’s disease (osteitis deformans) = increased osteoclast activity

9. Bone matrix 1/3 organic = flexibility collagen protein-carbo complexes 2/3 inorganic = strength calcium phosphate salt magnesium, sodium, potassium… Osteogenesis imperfecta = impaired osteoblast function, collagen unorganized, brittle bones Calcium and vitamin D need vitamin D to absorb calcium in the small intestine need UV to make vitamin D osteomalacia (rickets) = deficient vit D, soft bones

10. Shell-less chick no calcium, no ossified bone

11. Bone deposition = resorption Osteoporosis = porous bones decreased deposition increased resorption spongy bone affected bones become brittle women > men less bone mass lose it earlier & faster decrease in estrogen build bone mass ???!

12. Drink milk? What about my latte milk? Does that count? Things that affect bone resorption or deposition: corticosteroids – reduce osteoblast activity (matrix synthesis) increase osteoclast activity estrogen & testosterone – increase osteoblast activity caffeine – binds Ca so it’s excreted smoking – decrease osteoblast production, impairs Ca absorption, interferes with ERT

13. www.pdrhealth.com/ Osteoporosis and Anatomy…. Areas with more spongy bone kyphosis

14. Hip fracture complications