Bone Physiology - Formation of Bone. Intramembranous ossification. Flashcards
What does osteoblasts do ?
BUILDS BONE
(Forms bone)
What do Osteoclasts do ?
Cut down the bone !!
(Reabsorb bone)
It releases enzymes and H+ ions, which form with cl- ions to form HCL and demineralise the bone by breaking down calcium and phosphate.
What are osteogenic cells ?
- Undifferentiated stem cells, which develop into osteoblasts.
What do osteocytes do ?
Maintain bone mineral matrix
What are the four types of bone cells?
- Osteogenic cells
- Osteoblasts
- Osteocytes
- Osteoclasts
What is ossification (osteogenesis)?
Is the process of bone formation.
The process of converting other types of connective tissue into bone.
What is the process of converting other types of connective tissue into bone ?
Officiation or osteogenesis.
There are two types of ossification.
What are they?
What do they do?
Intramembranous - Bone develops from mesenchyme and forms mostly flat bones.
Endochondral ossification - Bone replaces existing cartilage, and this forms short and long bones.
Explain intramembranous ossificaation.
- When does it begin
- What does it develop form
- What bones does it form ?
- Give an example of these bones.
What process forms flat bones ?
Intramembranous ossification.
What do trapped osteoblasts eventually turn into ?
Osteocytes
In intramembranous ossification, what cells convert into osteoblasts?
Mesenchymal cells directly convert into osteoblasts.
in Intramembranous ossification Accumulating osteoid between the embryonic blood vessels form a random network called what ?
Trabeculae
in Intramembranous ossification Vascularised Mesenchyme condenses on the external face of the woven bone to form what ?
Periosteum
What forms the spongy bone ?
The central trabeculae and its vasculature forms spongy bone – becomes red bone marrow
In intramembranous ossification, the trabeculae beneath the periosteum thicken; what does this form?
Compact bone
Give a summary of intramembranous ossification.
