Bone Flashcards
What are the 4 functions of bone?
Weight bearing/support
Protection
Mineral Store
Blood formation
Name the 6 structures of bone.
Compact bone Trabecular bone Blood Vessels Medullary Cavity Bone marrow Membranes (periosteum/endosteum)
How is compact bone organised?
Into circular structures called Osteons/Haversian systems.
Define osteons.
Made up of sheets of bone around the Haversian canal.
What is trabecular bone made of?
Lamellated trabeculae filled with bone marrow.
Nme 6 types of bones and an example.
Flat bone - skull Sutural bone - joints in skull Long bone - limbs Short bones - hands and feet Irregular bone - vertebra Sesamoid bones - patella
Define endochondral bone formation.
Most common, includes long bone growth found inside cartilage.
Define intramembranous bone formation.
Flat bone e.g clavicle and found between membranes.
Define ossification.
In bone remodelling it is the process of laying down new bone material by cells called osteoblasts.
What is the process of endochondral ossification?
Forms as cartilage model first Blood vessels invade Cartilage is replaced by bone Cartilage remains in epiphyseal growth plate Growth plate eventually ossifies
What is the process of intramembranous ossification?
No cartilage phase
Mesenchymal cells develop into osteoprogenitor cells which mature into osteoblasts
Residual mesenchymal develop blood vessels and bone marrow
What is bone made of?
Cells (osteoblasts, osteocytes and osteoclasts) and extracellular matrix.
What are the functions of minerals and collagen in the bone?
Minerals keep them stiff and good for support whilst collagen gives the bone flexibility, reducing the risk of fracture.
Define bone remodelling.
A constant process which occurs in healthy bone as it will continue to remove and reform.
Define osteoblasts.
Immature bone cells which produce bone matrix and initiate calcification.
