ANA1 L5 Skeletal

• How does the proportion of bones and cartilage in the skeleton change as a person grows?


  The younger the person, the more cartilage they have
• What are the functions of bones?


  • Provides support and protection
  • Allows body movements through skeletal muscle contraction
  • Stores minerals (calcium and phosphorus) and fats
  • Site of blood cell production within bone marrow
• What is the primary characteristic of bone?


  Hard and makes up most of the skeleton
• What is the primary characteristic of cartilage?


  Resilient and semirigid, avascular and aneural
• What is the function of articular cartilage?


  Provides smooth, low-friction, gliding surfaces for free movement
• What is the periosteum?


  A fibrous connective tissue covering surrounding each bone
• What is the perichondrium?


  A fibrous connective tissue covering surrounding cartilage
• What are the functions of the periosteum and perichondrium?


  • Cover each bone/cartilage
  • Lay down more bone/cartilage during fractures
  • Nourish the external aspects
  • Provide interface for attachment of tendons and ligaments
• What are the types of bones according to shape?

  1. Long
  2. Short
  3. Flat
  4. Irregular
  5. Sesamoid
• What are the characteristics of long bones?


  Longer than they are wide
• Give examples of long bones.

  Humerus, ulna, radius, femur, tibia, fibula, metacarpals, metatarsals, phalanges
• What are the characteristics of short bones?


  As broad as they are flat
• Give examples of short bones.

  Carpals, tarsals
• What are the characteristics of flat bones?


  Thin, flattened shape
• Give examples of flat bones.

  Skull, scapulae, sternum, ribs
• What are the characteristics of irregular bones?


  Irregular shape
• Give examples of irregular bones.


  Vertebrae, facial bones
• What are the characteristics of sesamoid bones?


  Develop in certain tendons
• Give an example of a sesamoid bone.


  Patella
• What are the types of bones according to histological structure or porosity?

  1. Compact
  2. Cancellous or spongy
• What are the characteristics of compact bone?


  Mostly solid matrix and cells, has haversian system
• Where is compact bone located?


  Diaphysis of long bones and surfaces of all other bones
• What are the characteristics of cancellous or spongy bone?


  Consists of a lacy network of bone with many small marrow-filled spaces
• Where is cancellous bone located?


  Epiphysis of long bones and interior of all other bones
• What are the types of bones according to location?

  1. Axial
  2. Appendicular
• What does the axial skeleton consist of?


  Head, neck, and trunk
• How many bones are in the axial skeleton?


  80 bones
• What does the appendicular skeleton consist of?


  Bones of the limbs and girdles
• How many bones are in the appendicular skeleton?


  126 bones
• What are the bones in the pectoral girdle and upper limbs?

  • Pectoral Girdle: Scapula (2), Clavicle (2)
  • Upper Limbs: Humerus (2), Radius (2), Ulna (2), Carpals (16), Metacarpals (10), Phalanges (28)
• What are the bones in the pelvic girdle and lower limbs?

  • Pelvic Girdle: Coxal bones (2)
  • Lower Limbs: Femur (2), Tibia (2), Fibula (2), Patella (2), Tarsals (14), Metatarsals (10), Phalanges (28)
• What are the types of bones according to bone ossification?

  1. Intramembranous ossification
  2. Endochondral ossification
• What is intramembranous ossification?


  Bone formation occurs within the connective tissue membrane
• Where does intramembranous ossification begin?


  In areas called ossification centers
• What is endochondral ossification?


  Bone formation occurs from cartilage
• What are the types of bone growth?


  1. Growth in diameter
  2. Growth in length
• How does bone grow in diameter?

  Osteoblasts deposit new bone matrix on the surface of bones
• How does bone grow in length?


  Occurs in the epiphyseal plates
• What are the parts of a long bone?

  1. Epiphysis
  2. Diaphysis
  3. Metaphysis
  4. Periosteum
• What is the epiphysis of a long bone?


  Ends of the long bone