SKELETAL

• Bones


  • Rigid & Strong; major
• Cartilage


  • Firm yet flexible, supports within structures, acts as padding within joints
• Ligaments


  • Strong fibrous connective tissue, connect bone to bone, prevent excessive movement
• Tendons


  • Strong connective tissue, connect muscle to bone
• Joints


  Two bones joined together
• Bone components


  • Collagen (Type 1) - provides flexibility & structure to withstand stress, acts as a reinforcing mesh
  • Water (10-20%) - hydrates and makes bones dynamic
  • Osteoblasts - bone formation
  • Osteocytes - bone maintenance, slows down
  • Osteoclasts - bone-resorbing, remodeler
  • Osteoid - mix of collagen + proteins
  • Inorganic mineral salts (45%) - part of bone matrix, provide strength & rigidity, act as "cement", include Hydroxyapatite crystals
  • Bone marrow - site of cell production, contains red and white blood cells
• Woven bone


  Temporary bone in babies
• Lamellar bone


  Permanent bone
• Spongy bone


  • Porous
• Compact bone


  • Solid
• Types of bone


  • Long - smaller width, found in limbs
  • Short - wide and long, found in wrist and ankle
  • Flat - thin and flat, act as barriers
  • Irregular - specialized
• Axial bones


  • Skull
  • Vertebral column (spine)
  • Thoracic cage (rib cage)
• Appendicular bones


  • Shoulder blades (scapular)
  • Pelvis
  • Limbs
• Cartilage


  • Contains chondroblasts, chondrocytes, lacuna (spaces for chondrocytes), and is surrounded by perichondrium with blood vessels and nerves
• Growth of cartilage


  1. Appositional growth - at the start and end

  2. Interstitial growth - in the middle
• Joint classification by structure

  • Synarthroses - no movement (fibrous)
  • Amphiarthroses - slight movement (cartilaginous)
  • Diarthroses - free movement (synovial)
• Joint classification by function

  • Synarthroses - no movement (fibrous)
  • Amphiarthroses - slight movement (cartilaginous)
  • Diarthroses - free movement (synovial)