Lecture 11: Osteogenesis and joints

Question 1

Aggregation of mesenchymal cells is controlled by

Answer 1

Wnt, Hedgehog, FGF, TFG-B

Question 2

Mesenchymal cells become

Answer 2

Osteoblasts

Question 3

Mineralization occurs via

Answer 3

Calcium ions

Question 4

Primary ossification center becomes

Answer 4

Trabecula

Question 5

Step one of intramembranous ossification

Answer 5

Mesenchymal cells aggregate without a cartilage intermediate. Process controlled by Wnt, hedgehog, FGF, TGF-B

Question 6

Step two of intramembranous ossification

Answer 6

Mesenchymal cells differentiate into osteoblasts.

Bone blastema is formed

Question 7

Step three of intramembranous ossification

Answer 7

Bone matrix is deposited by osteoblasts. Later Calcium, transported by blood vessels, is used in the mineralization process and primary bone tissue is formed

Question 8

Step one EBF

Answer 8

Chondrocytes become hypertrophic

Question 9

Step two EBF

Answer 9

Chondrocytes secrete vascular endothelial growth factor

Question 10

Step three EBF

Answer 10

Blood vessels break through perichondrium, bringing osteoprogenitor cells with them

Question 11

Step four EBF

Answer 11

Hypertrophic chondrocytes undergo apoptosis, leaving behind thin strands of calcified matrix

Question 12

Step five EBF

Answer 12

Osteoblasts use calcified strands as substrates for deposition of osteoid

Question 13

Step six EBF

Answer 13

Osteoid is calcified

Question 14

Cartilage is added to the _______ end of the epiphyseal plate

Answer 14

Distal end

Question 15

Cartilaginous joints

Answer 15

Symphysis

Synchondrosis

Question 16

Symphysis

Answer 16

Joined by fibrocartilage

Include intervertebral discs and pubic symphysis

Question 17

Synchondrosis

Answer 17

Joined by hyaline cartilage

Include epiphyseal plate and first sternocostal joint

Question 18

Synarthroses (fibrous) joints

Answer 18

Suture-joints between bones of calvaria
Gomphosis- peg-in-socket.. teeth in alveoli
Syndesmosis-interosseous membrane

Question 19

Monoaxial joints

Answer 19

Hinge-humeroulnar

Pivot-radioulnar

Question 20

Biaxial

Answer 20

Condyloid-metacarpophalangeal

Saddle- first carpometacarpal joint

Question 21

Triaxial

Answer 21

Ball and socket- glenohumeral

Question 22

Synovial joint structures

Answer 22

Articular cartilage
Joint capsule
Synovial membrane
Synovial fluid
Synovial cells

Question 23

Articular cartilage

Answer 23

Hyaline cartilage
Lacks perichondrium
Not line by synovial membrane

Question 24

Joint capsule

Answer 24

Vascularized dense CT
Lined by synovial membrane
Attached to edges of articular cartilage

Question 25

Synovial membrane

Answer 25

Highly vascularized
1-3 layers of synovial cells
No basal lamina

Question 26

Synovial fluid

Answer 26

Contains mucin

Produced by synovial cells

Question 27

Synovial cells

Answer 27

Type A- Macrophage like

Type B- Fibroblast like