bone formation and repair Flashcards
what 4 situations does bone formation occur
in embryo and foetus
growth
remodeling
repair of fractures
name the 2 mechanisms of bone formation
intramembranous ossification
endochondral ossification
which mechanism of bone formation is the simplest
intramembranous ossification
what is the basics of intramembranous ossification
bone forms directly in mesenchyme layers
what is the basics of endochondral ossification
forms within hyaline cartilage developed from mesenchyme
what is mesenchyme
an embryonic tissue layer model that is replaced with bone
name the stages of intramembranous ossification
1 development of ossification center
2 calcification
3 formation of trabeculae
4 mesenchyme condenses at periphery
describe the development of the ossification center during intramembranous ossification
mesenchyme cells differentiate into osteogenic cells and then to osteoblasts
osteoblasts secrete organic matrix
describe calcification during intramembranous ossification
lacunae extend cytoplasmic processes to each other
deposit calcium and other mineral salts
describe the formation of trabeculae during intramembranous ossification
spongy bone
blood vessels grow in and red marrow is formed
describe mesenchyme condenses during intramembranous ossification
periphery turns into periosteum
name the steps of Endochondral Ossification
1 develop a cartilage model
2 growth
3 ossification
4 osteoblasts break some bone down
5 blood vessels enter epiphysis
describe the development of a cartilage model during Endochondral Ossification
mesenchyme cells crowd together in shape of a bone and turn into chondroblasts
describe growth during Endochondral Ossification
chondroblasts secrete cartilage
perichondrium forms on the surface
internal chondrocytes in lacunae die and form small cavities
