Bone and Cartilage

Question 1

types of bone

Answer 1

cortical, compact
- 80-98%, external
cancellous, spongy bone
- 15-20%, internal

Question 2

alveolar bone

Answer 2

nutrients canals with blood vessels
lines tooth socket, peentrated by collagen sharpeys fibres

Question 3

composition of bone

Answer 3

60% inorganic - hydroxyapatie
25% irganic - collagen
15% water

Question 4

woven and lamellar bone

Answer 4

woven - rapidly laid down, fracture repair, many osteocytes
lamellar - slowly laid down, normal in adult, few osteocytes

Question 5

compact bone structure

Answer 5

laid down like lamellar [slow], longitudinal columns, contain blood, volkmans canals

Question 6

bone cells

Answer 6

osteoblasts - lie on surface of bone, mesenchymal stem cells, secrete collagen fibres
osteocytes - odontoblasts trapped in bone
osteoclasts - large multinucleate cells, relates to macrophages, absorb bone

Question 7

bone remodelling

Answer 7

regulated by hormones [parathyroud, caclitonin, cytokines]
replacement wihtout change in shape, controlled by osteoblasts

Question 8

cartilage

Answer 8

semi-rigid, un mineralised connective tissue, similar to bone
hyaline - widespread, larynx, nasal
fibrocartilage - invertebral discs
elastic - external ear, epiglottis
cells formed by chondroblasts

Question 9

endochonral and intramembranous ossification

Answer 9

endochondral - long bone, cartilage then bone
intramembranous - flat bones, no cartilage precusrosr

Question 10

achondroplasia

Answer 10

genetic defect of cartilage growth
endochondral bone growth impaired, intramembranous unaffected