musculoskeletal system

• Functions of the skeleton

  • Supports the body
  • Working with the muscular system, moves the body
  • Protection
  • Produces blood cells
  • Stores minerals and fat
• Osteocytes


  Bone cells responsible for forming new bone
• Osteoblast


  Bone cells that maintain the mineral concentration of the matrix via the secretion of enzymes
• Osteoclast


  Bone cells responsible for bone resorption, or breakdown
• Osteon


  A unit of bone containing central canal and matrix rings
• Ossification


  Process of bone formation
• Types of bone tissue

  • Compact bone
  • Spongy bone
• Epiphysis


  • Ends of the bone, composed mostly of spongy bone enclosed by thin layer of compact bone
• Epiphyseal plate/line


  • Flat plate of hyaline cartilage seen in young, growing bone, causes lengthwise growth of a long bone
• Articular cartilage


  • Covers the external surface of the epiphyses, made of hyaline cartilage, decreases friction at joint surfaces
• Diaphysis


  • Shaft of the bone, makes up most of bone's length, composed of compact bone
• Periosteum


  • Outside covering of the diaphysis, fibrous connective tissue membrane
• Marrow (medullary) cavity


  • Cavity inside the shaft, contains yellow marrow (mostly fat) in adults, contains red marrow for blood cell formation in infants
• Organization of the skeleton

  • Axial skeleton
  • Appendicular skeleton
• Axial skeleton


  • Skull
  • Hyoid bone
  • Vertebral column
  • Ribs and sternum
• Vertebral column


  • Protects spinal cord
  • Regions: cervical, thoracic, lumbar, sacral, coccygeal
• Intervertebral disks


  • Cushion vertebrae, assist in movement and flexibility
• Ribs

  • Protect the thoracic cavity, 12 pair, 10 pair attached to vertebrae and sternum, 2 pair are "floating"
• Sternum

  • Breastbone, protects heart
• Skeletal muscle


  Attaches to skeleton and provides strength and mobility
• Cardiac muscle


  Exclusively in the heart
• Smooth muscle


  Walls of digestive tract, blood vessels, uterus, ureters
• Skeletal muscles


  • 600 skeletal muscles
  • synergistic muscles - work together, help prime move.
  • antagonistic muscles - oppose each other
  • agonist - chiefly responsible for reproducing a movement
  • attach to bones via tendons
• Origin

  End of muscle that attaches to relatively stationary bone
• Insertion

  End of muscle attached to movable bone.
• Structural classification of joints

  • Fibrous joints
  • Cartilaginous joints
  • Synovial joints
• Synovial joints


  • Articulating bones separated by a joint cavity, contain synovial fluid
• Types of synovial joints based on shape

  • Plane joint
  • Hinge joint
  • Pivot joint
  • Condylar joint
  • Saddle joint
  • Ball-and-socket joint
• Joints, also known as articulations, are a form of connection between bones
• Joints


  Hold bones together and allow for mobility
• Structure of cranial bones

  frontal, parietal, temporal, sphenoid, ethmoid, occipital, nasal, lacrimal
• how many bones are found in adult?

  206
• How are bones classified based on shape?

  
  

  long

  short

  flat

  irregular
• what do cranial bones do?

  protect the brain
• cranial bones (8)

  parietal - 2

  temporal - 2

  frontal

  occipital

  sphenoid

  ethmoid
• facial bone (14)

  nasal - 2

  zygomatic - 2

  maxilla - 2

  mandible - 1

  lacrimal - 2

  palatine - 2

  inferior nasal conchae - 2

  vomer - 1
• What is sinuses?

  air spaces within sevral cranial and facial bones.
• What are three types of muscles?

  skeletal, cardiac, smooth
• four distinguishing features of synovial joints

  articular cartilage, articular capsule, joint cavity, reinforcing ligaments
• cells involved in the development and maintanance of bone

  • chondroblast - cartilage-forming cells.
  • osteoblasts - young bone-forming cells.
  • osteocytes - mature bone cells. maintain bone matrix.
  • osteoclasts - bone-dissolving cells.