The Skeletal System

• The skeletal system consists of?

  • bones
  • cartilages
  • tendons
  • ligaments
• Made up of hydroxyapatite crystals.

  Bones
• Collagen fibers, hyaline, elastic & fibrocartilage.

  Cartilage
• Attaches bone to muscles.

  Tendons
• Attaches bone to bone.

  Ligaments
• What are the functions of the skeletal system?

  • Support
  • Protection
  • Movement
  • Storage
  • Hematopoiesis (blood production)
• Stores minerals in bones such as calcium and phosphorus.

  Storage
• 99% of calcium is stored in?

  Bone
• 1% of calcium is stored in?

  Blood
• Hema means?

  Blood
• Poesis means?

  Production
• Long bones consist of?

  • Epiphysis
  • Diaphysis
• Center portion of the bone.

  Diaphysis
• Ends of a long bone.

  Epiphysis
• It covers the ends of the epiphyses where the bones articulate (join) with other bones.

  Articular cartilage
• Between each epiphysis and diaphysis.

  Epiphyseal plate (growth plate)
• When bone growth stops, the cartilage of each epiphysis is replaced by bone and be?

  Epiphyseal line
• It is where the growth of the bone by length.

  Epiphyseal plate
• Has red bone marrow and this is where hematopoiesis occurs.

  Epiphysis
• Has yellow bone marrow.

  Diaphysis
• The cavity inside the diaphysis.

  Medullary cavity
• It is filled with soft tissue called marrow.

  Medullary cavity
• Consists mostly of adipose tissue.

  Yellow marrow
• Consists of blood-forming cells and is the only site of blood formation in adults.


  Red marrow
• In adults, red marrow is confined to the bones in the central axis of the body and in the most proximal epiphyses of the limbs.
• Hematopoiesis happens here.


  Red marrow
• Dense connective tissue that covers the outer surface of the bone.

  Periosteum
• Thinner connective tissue membranes that line the surface of the medullary cavity.

  Endosteum
• What are the cells of the bone?

  • Osteoblasts
  • Osteocytes
  • Osteoclasts
• Bone-forming cells

  Osteoblasts
• Function in the formation of the bone.

  Osteoblasts
• This cell of the bone forms fibers.

  Osteoblasts
• Repair and remodeling of the bone.

  Osteoblasts
• Mature bone-cells.

  Osteocytes
• When osteoblasts are surrounded by matrix, they become?

  Osteocytes
• Bone-destroying cells.

  Osteoclasts
• Responsible for bone resorption and remodeling.

  Osteoclasts
• Cells or tissues are destroyed so that the minerals stored in the bones can be released a little into the blood to maintain calcium homeostatic levels.

  Bone resorption
• In what instances do repairs and remodeling happen?

  If there is a fracture.
• What are the two major types of bone based on their histological structure?

  • Compact bone
  • Spongy (cancellous bone)