Osteochondrogenesis/Joint Components Flashcards
What are the two types of bone histogenesis?
Intromembranous and endochondral bone formation
What is bone remodeling?
The combination of bone formation and resorption
Is remodeling faster in primary or secondary bone?
Primary Bone
What is the relationship of Ca and bone?
Bone stores Ca used to buffer the levels of Calcium present in the blood.
Describe the mineral and H2O content of old osteons.
Highest mineral concentration and lowest H2O content
Describe the process of osteoclast activity.
Erosion tunnel and 2 weeks later, apoptosis
Describe the process of new bone being laid down
Osteoblasts –> cementing substance (forms cementing/reversal line) –> blasts get caught, become cytes.
Name flat bones.
Skull, facial bones, mandible, clavicle, pelvis
What type of tissue houses intramembranous bone formation?
Highly vascular mesenchymal tissue
List a few signalling factors involved in intramembranous bone formation.
Wnt, hedgehog, FGF, TGF-beta
What forms a primary ossification center?
Condensed mesenchymal cells, which differentiate into osteoblasts
What do the osteoblasts in intramembranous bone formation secrete?
Osteoid collagen
Whats another term for the bone formed with osteoid collagen?
Woven Bone
Collagen secretion eventually causes osteoblasts to…
become caught in the matrix, becoming osteocytes. These unite to form trabeculae.
How is spongy bone made?
Fusion of bony trabeculae, followed by invasion of blood vessels, and mesenchymal differentiation into bone marrow.
What does mesenchymal tissue that doesn’t undergo ossification become?
Periosteum and Endosteum
Woven bone is eventually converted into _______ ____ in the outer layers.
Lamellar Bone
Endochondral bone formation is used to make ____ _____ using _______ _________ as a scaffold.
Long Bones. Hyaline Cartilage.
What are the two stages of endochondral bone development?
Development of primary ossification center, development of secondary ossification centers.
Where does the primary center of ossification occur?
The midriff of the diaphysis
What does vascularization do to the perichondrium?
Converts chondrogenic cells to osteoprogenitor cells (which form osteoblasts)
After osteoprogenitor cell development, perichondrium converts to….
Periosteum
First region of bone generated by osteoprogenitors is…
Subperiosteal bone collar