anatomy 3

Question 1

What does the skeletal system include?

Answer 1

• Bones
• Cartilage
• Joints
• Ligaments
• Other connective tissues

Question 2

What are 5 functions of the skeletal system?

Answer 2

• Support against gravity
• Storage of calcium and fat
• Blood cell production
• Protection of soft internal organs
• Leverage for muscle action

Question 3

What are characteristics of bone(osseous tissue)?

Answer 3

• Specialized cells; 2% of bone weight
• Strong matrix made of calcium phosphate; 2/3 of weight
• collagen fibers

Question 4

What are the general shapes of bones and give an example?

Answer 4

• Long bone
  •humerus/femur
• Short bone
  •carpal bones
• Flat bone
  •Parietal bone
• Irregular bone
  •vertebra

Question 5

What are features of a long bone?

Answer 5

• Diaphysis(shaft)
  • contains compact bone
  • marrow cavity
• Epiphyses(ends)
  • Spongy bone
• Articular cartilage
• Periosteum(covering)
• Endosteum(lining)

Question 6

What are features of the periosteum?

Answer 6

• Outer fibrous layer
• Inner cellular layer

Question 7

What are features of osteocytes?

Answer 7

• In the lacunae(holes) in matrix
• Between lamellae of matrix
• Branches with canaliculi

Question 8

What are other features of the bone?

Answer 8

• Osteon - the basic functional unit of compact bone; column shape
• Strong in long axis of bone
• Concentric layers of osteocytes and. matrix
• Central canal; axial tunnel for blood vessels
• Perforating canal; radial tunnel for blood vessels

Question 9

What are features of spongy bone?

Answer 9

• No osteons
• Lamellae as trabeculae
  • Arches, rods, plates of bone
  • Branching network of bony tissue
  • Strong in many directions
  • Red marrow space

Question 10

What are the cells in bone?

Answer 10

• Osteocytes
  • Mature bone cells between lamellae
• Osteoclasts
  • Source of acid, enzymes for osteolysis
  • Calcium homeostasis
• Osteoblasts
  • Responsible for osteogenesis (new bone)
  • Source of collagen, calcium salts

Question 11

What is Intramembranous Ossification ?

Answer 11

• Ossification—Process of converting other tissues to bone
• Forms flat bones of skull, mandible, clavicle
• Stem cells differentiate to osteoblasts
• Produces spongy bone, then compact bone