CHAPTER 5 appositional growth articular cartilage canaliculi comminuted fracture compact bone compound fracture compression fracture diaphysis epiphyseal plate epiphyses greenstick fracture hematopoiesis lacunae ossification osteoblasts osteoclasts osteocytes osteon (Haversian system) periosteum rickets sesamoid bones Sharpey's fibers simple fracture spongy bone (24) I. Bones (overview) A. skeleton subdivisions 1. ______skeleton – bones that form longitudinal axis of body 2. _______skeleton – bones of limbs and girdles B. bone functions 1. __________ a. forms internal framework b. supports and anchors all soft organs 2. __________ protect soft body organs 3. __________ attachment for skeletal muscles via tendons 4. __________ a. stores _____ in internal cavities b. storehouse for minerals (> imp. is Ca & P) 5. ___________________________ a. also called _____________ b. occurs in marrow cavities of certain bones c. red marrow blood cells C. bone classification 1. 2 basic types of bone (osseous) tissue: a. __________ bone – dense, looks smooth and homogeneous b. __________ bone – composed of small needle-like pieces of bone & open space 2. classified according to shape: a. _____ bones 1. longer than they are wide 2. have a shaft w/ heads @ both ends 3. bones of limbs (except wrist & ankle) b. ________ bones 1. usu. cube-shaped & spongy bone 2. bones of wrist & ankle 3. __________ bones – *special type of short bone *form w/i tendons (patella) c. _________ bones 1. thin, flattened, usu. curved 2. layer of spongy bone b/t 2 layers of compact bone 3. most bones of skull d. __________ bones 1. vertebrae (make up spinal col.) 2. hip bones (coxal) Long – yellow Short – light green Flat – purple Irregular – light blue Sesamoid – orange Axial skeleton – red Appendicular skeleton - blue D. Long bone structure 1. gross anatomy a. __________ *shaft *makes up most of bone’s length *composed of compact bone b. __________ *protective membrane-covering of diaphysis c. __________ __________ *also called perforating fibers *c.t. fibers that secure periosteum to bone d. __________ *ends of long bones *area of spongy bone enclosed in thin layer of compact bone e. __________ __________ *covers external surface of epiphyses *glassy hyaline cartilage *provides a smooth, slippery surface to reduce friction @ joints f. ____________ __________ *flat plate of hyaline cartilage *seen in young, growing bone *causes _________ growth of a long bone g. __________ __________ *also called the ______ ______cav. *cavity of the shaft *adultsstorage area for adipose tissue *infantscontains red marrow & forms blood cells (adults: red marrow is found only in spongy bone cavities of flat bones & epiphyses) Epiphysis – dark green Epiphyseal line – light green Diaphysis – brown Articular cartilage – purple Periosteum – blue Spongy bone/red marrow – red Compact bone – pink Medullary cavity/yellow marrow – yellow Nutrient artery - orange 2. microscopic anatomy a. ____________ *mature bone cells b. ____________ *tiny cavities w/i matrix *contain osteocytes c. ____________ *concentric circles in wh/ lacunae are arranged d. ____________ _______ *central canals around wh/ the lamella form NOTE: see page 92 for micrograph of the structure of bone e. __________ *also called ______________ system *each complex consisting of a central canal + matrix rings *canals run lengthwise carrying blood vessels & nerves to all areas of bone f. ____________ *transportation system *connect bone cells to __________ __________ *radiate o/w from the central canals to all lacunae *reason bone cells are well nourished 3. bone markings (pg.134) a. __________ *shallow, basinlike depression in a bone *may serve as an _________ surface b. __________ *narrow, slit-like opening c. __________ *round/oval opening through a bone *for blood vessels &/ nerves E. Bone formation, growth, remodeling 1. formation & growth a. ______________ *process of bone formation *2 phases -____________ (bone forming cells) cover hyaline cartilage -hyaline cartilage is digested away forming medullary cavity b. ____________ growth *increase in diameter of bone c. ____________ *bone-destroying cells 2. bone remodeling a. nec. for bones to retain normal prop. & strength as body increases in size & strength b. PTH (____________ ____________) *determines when bone is to be broken down/formed *___________ (muscle pull, gravity) determine where bone matrix is to be broken down/formed c. allows skeleton to remain as strong & vital as possible during growth, injury, etc. F. Problems 1. __________ a. childhood disease in wh/bones fail to calcify b. bones soften bowing of legs c. usu. due to lack of ___ or lack of Vit. D wh/ is needed to absorb Ca into bloodstream 2. Fractures (bone breaks) a.__________ (closed) *bone breaks cleanly *does NOT penetrate the skin b. __________ (open) *bone ends penetrate through the skin Simple fracture Compound fracture comminuted c. __________ fracture *bone breaks i/t many fragments *common in elderly (bones are more brittle) d. __________ fracture *bone is crushed *common in porous bones e. __________ compression *incomplete break *common in children (flexible bones) Greenstick ---------- 3. fracture repair (pg. 138) 4 mj. Events: a.___________ forms blood-filled swelling b. break is splintered by a __________ callus c. __________ __________is formed fibrocartilage is gradually replaced by spongy bone d. bone remodeling occurs