Bone Structure & Composition

Question 1

long bone composed of…

Answer 1

• diaphysis
• medullary cavity
• epiphysis
• epiphyseal plate
• epiphyseal line
• endosteum
• periosteum membrane
• articular cartilage

Question 2

long bone: diaphysis

Answer 2

• shaft/body of bone

- compact bone

Question 3

long bone: medullary cavity

Answer 3

• red bone marrow (child)
• yellow bone marrow (adult)
• lined with endosteum

Question 4

long bone: epiphysis

Answer 4

proximal and distal parts

Question 5

long bone: epiphyseal plate

Answer 5

• hyaline cartilage

- bone growth occurs (endochondral ossification)

Question 6

long bone: epiphyseal line

Answer 6

• replaces plate after growth

Question 7

long bone: endosteum

Answer 7

• delicate CT
• lines internal surfaces + canals in compact bone
• osteoblasts + osteoclasts

Question 8

long bone: periosteum membrane

Answer 8

• fibrous CT

- allows diameter growth

Question 9

long bone: articular cartilage

Answer 9

• prevents friction

- epiphysis surface

Question 10

bone

Answer 10

• compact/spongy
• osteoprogenitor cells give rise to: osteoblasts, clasts, cytes
• cells of CT are separated by matrix (collagen fibers, ground substance, water)

Question 11

compact bone

Answer 11

• exterior surface of bones

- composed of osteon + haversian system

Question 12

compact bone: osteon consists of…

Answer 12

• lamellae: circle of bone matrix (osteocytes between)
• canaliculi: connect cells to blood vessels
• haversian canal: contain blood vessels + nerves
• volkmann’s canal: right angles of blood vessels and nerves (connects periosteum to endosteum)

Question 13

spongy bone

Answer 13

• plates called trabeculae
• irregular lamellae
• found in epiphysis of long bone + flat bones
• contain red bone marrow
• produce blood cells + blood supply to osteocytes

Question 14

functional classification

Answer 14

1) synarthrotic: immoveable joints
2) amphiarthrotic: slightly moveable joints
3) diarthrotic: freely moveable joints

Question 15

structural classification

Answer 15

1) fibrous joints: no joint cavity (fibrous CT)
2) cartilaginous: no joint cavity (hyaline cartilage)
3) synovial joints: - cavity filled with synovial fluid
- cavity + ligaments hold bones

Question 16

synovial joints consists of…

Answer 16

articular cartilage
joint cavity
joint capsule

Question 17

synovial joints: articular cartilage

Answer 17

• cartilage at end of bones

- reduce friction

Question 18

synovial joints: joint cavity

Answer 18

contains synovial fluid

Question 19

synovial joints: joint capsule

Answer 19

• outer layer > periosteum

- inner synovial membrane secretes synovial fluid

Question 20

types of synovial joints

Answer 20

1) gliding: flat surfaces
2) hinge: concave or convex surface
3) pivot:
4) ball + socket: freedom of movement