Skip to main content
Back

Chapter 6

Control buttons has been changed to "navigation" mode.
1/16

Terms in this set (16)

  • Classify sternum, humerus, vertebra, os coxa
    Sternum and vertebra are axial bones; humerus and os coxa are appendicular bones.
  • Define foramen, fossa, condyle, tuberosity
    Foramen: small passageway for vessels or nerves.
    Fossa: shallow depression.
    Condyle: smooth rounded articular projection.
    Tuberosity: small rough projection over a broad area.
  • Difference between red and yellow marrow
    Red marrow produces blood cells.
    Yellow marrow stores fat (adipose) as an energy reserve.
  • What is an osteogenic cell?
    A stem cell that differentiates into osteoblasts; essential for fracture repair.
  • Function of osteoclasts
    Cells that break down bone matrix through osteolysis, releasing minerals.
  • Describe the structure of an osteon
    Concentric lamellae surround a central canal with blood vessels; osteocytes reside in lacunae connected by canaliculi.
  • What are trabeculae?
    Struts and plates of lamellae forming spongy bone; provide strength with low weight and house red marrow.
  • Intramembranous vs. endochondral ossification
    Intramembranous: mesenchymal cells become osteoblasts directly (skull roof, mandible, clavicle).
    Endochondral: hyaline cartilage model replaced by bone (long bones like femur).
  • How does a bone widen?
    By appositional growth: osteogenic cells in periosteum form osteoblasts adding circumferential lamellae; osteoclasts enlarge medullary cavity.
  • What is the epiphyseal plate and what happens at closure?
    Cartilage plate that grows and is replaced by bone to lengthen bone; at puberty, osteoblasts outpace chondrocytes, plate closes leaving an epiphyseal line.
  • Body's response to low blood calcium
    Parathyroid hormone (PTH) increases: osteoclasts release calcium, intestines absorb more, kidneys conserve calcium; calcitonin lowers blood calcium.
  • Other physiological roles of calcium
    Calcium is essential for muscle contraction, blood clotting, and nerve impulse transmission.
  • Four stages of bone repair
    Hematoma: clot forms.
    Soft callus: fibrocartilage bridge.
    Hard callus: spongy bone replaces soft callus.
    Remodeling: reshaping into compact and spongy bone.
  • Name these fractures: shattered; distal radius; bone through skin
    Comminuted: shattered bone.
    Colles: fracture of distal radius.
    Open (compound): bone breaks through skin.
  • Difference between gigantism and acromegaly
    Gigantism occurs before epiphyseal plate closure, causing longer bones; acromegaly occurs after closure, causing thicker bones.
  • Why does immobilization cause bone loss?
    Lack of mechanical stress reduces osteoblast activity; osteoclasts exceed osteoblasts, leading to net bone loss and decreased density.