bone histology

Question 1

type of collagen in hyaline cartilage?

Answer 1

II

Question 2

describe elastic cartilage and 2 places it can be found

Answer 2

hyaline cartilage with addition of elastin. ear & epiglottis

Question 3

describe fibrocartilage and which type of collagen is present. Where is it found?

Answer 3

dense connective tissue with isolated islands of cartilage. Collagen type 1.
IV discs, menisci.

Question 4

4 types of bone cells?

Answer 4

osteo……progentior, cyte, blast and clast

Question 5

where are osteoprogenitor cells found and what is their function?

Answer 5

periosteum & endosteum. give rise to new osteoblasts

Question 6

what is osteoid, what is it made from and which cell makes it?

Answer 6

ECM of bone, Collagen type I, Osteoblasts

Question 7

what is the significance of osteocyte loss?

Answer 7

bone resoprtion

Question 8

histological feature of osteoclast?

Answer 8

multi-nucleate Giant cell

Question 9

marker of osteoclast activity?

Answer 9

Tartrate-resistant acid phosphotase

Question 10

origin of osteoclast? which cell type related to? what happens when not required?

Answer 10

from bone marrow, relative of macrophages, apoptose when not required

Question 11

2 types of bone development?

Answer 11

membranous and endochondral

Question 12

origin of membranous bone and 3 examples.

Answer 12

mesenchyme. Skull, flat bones & calvicles

Question 13

describe endochondral bone formation?

Answer 13

cartilage laid down>blood vessels invade brining osteoprogenitors

Question 14

describe the 5 layers of the growth plate.

Answer 14

1. Resting - normal hyaline cartilage
2. Proliferative - dividing chondrocytes
3. Maturing - chondrocytes mature
4. Hypertrophic - chondrocytes hypertrophy and die
5. Ossification - degenerating cartilage is destroyed and new bone laid.

Question 15

what is a chondrocyte?

Answer 15

only cells found in cartilage

Question 16

what is woven bone. give 3 features. what eventually happens?

Answer 16

new bone (during development or repair). more cellular, more collagen, no haversian systems. Eventually osteoblasts and clasts remodel

Question 17

describe the haversian system

Answer 17

osteoclasts form a cavity in the bone> blood vessel comes in> osteoblasts line cavity> add layers inwardly toward vessel with collagen alternating directions.
Osteocytes present in layers