FUNCTIONS AND TYPES OF BONE

• Skeletal system includes


  • Bones of the skeleton
  • Cartilages
  • Ligaments
  • Other connective tissues
• Functions of Skeletal System

  • Support
  • Protection
  • Movement
  • Mineral Storage
  • Blood Cell Production
  • Energy Storage
• Support


  Bones provide a framework for the attachment of muscles and other tissues
• Protection


  Bones such as the skull and rib cage protect internal organs from injury
• Movement


  Bones enable body movements by acting as levers and points of attachment for muscles
• Mineral Storage


  Bones serve as a reservoir for calcium and phosphorus, essential minerals for various cellular activities throughout the body
• Blood Cell Production


  The production of blood cells, or hematopoiesis, occurs in the red marrow found within the cavities of certain bones
• Energy Storage


  Lipids, such as fats, stored in adipose cells of the yellow marrow serve as an energy reservoir
• Classification of Bones


  • Long
  • Short
  • Flat
  • Irregular
  • Sesamoid
  • Sutural
• Sutural bones


  Small, flat, oddly shaped bones found between the flat bones of the skull
• Sutural bones range in size from a grain of sand to a quarter
• Irregular bones


  Complex shapes with short, flat, notched, or ridged surfaces
• Examples of irregular bones

  • Vertebrae
  • Bones of the pelvis
  • Several bones in the skull
• Short bones


  Boxlike in appearance
• Examples of short bones

  • Carpal bones
  • Tarsal bones
• Flat bones


  Thin, parallel surfaces
• Examples of flat bones

  • Roof of the skull
  • Sternum
  • Ribs
  • Scapulae
• Long bones


  Relatively long and slender
• Examples of long bones

  • Femur
  • Bones in the arm and forearm
  • Thigh and leg
  • Palms
  • Soles
  • Fingers
  • Toes
• The femur is the largest and heaviest bone in the body
• Sesamoid bones


  Usually small, round, and flat
• Everyone has at least one sesamoid bone, the patella (kneecap)
• Structure of a long bone

  1. Diaphysis

  2. Epiphysis

  3. Metaphysis

  4. Medullary cavity

  5. Articular cartilage

  6. Periosteum

  7. Endosteum
• Diaphysis


  The shaft of a long bone
• Epiphysis


  The wide part at each end of a long bone
• Metaphysis


  Where diaphysis and epiphysis meet
• Medullary cavity


  The hollow area inside the diaphysis of a bone
• Articular cartilage


  A thin layer of cartilage covering each epiphysis
• Periosteum


  A strong fibrous membrane covering a long bone everywhere except at joint surfaces
• Functions of periosteum


  • Isolates bone from surrounding tissues
  • Provides a route for blood vessels and nerves
  • Participates in bone growth and repair
• Endosteum


  A thin membrane that lines the medullary cavity
• Structure of flat bones

  • Consist of spongy bone between two layers of compact bone
  • Within the cranium, the layer of spongy bone is called the diploë