Bone Growth Flashcards
What tissue forms the blueprint of the skeleton
Cartilage (bone later replaces this)
Define endochondral ossification
The process of forming bone from cartilage during growth in utero
Describe step 1 of endochondral ossification
Nucleation of CaCO3 minerals in centre of cartilage
Describe step 2 of endochondral ossification
Blood vessels form on surface, bring fibroblast, differentiate into OB
Describe step 3 of endochondral ossification
OB begin to lay down bone
Describe step 4 of endochondral ossification
Blood vessels become inside bone
Describe step 5 of endochondral ossification
OB create more bone in centre = create bone shaft
What is the location of primary ossification?
In the diaphyses (shafts)
What is the secondary site of ossification?
In the epiphyses
What is the growth plate known as?
The epiphyseal plate
What is the function of the growth/epiphyseal plate?
To enable lengthwise bone growth throughout childhood, as the diaphyses is not not attached to anything and thus can continue to grow
What process occurs in bones from about puberty onwards?
The epiphyses start to fuse with the diaphyses
Define appositional growth
Bone growth widthwise
What role do osteoblasts play in appositional growth?
OB adds bone matrix to the bone surface, create extra lamellae
What role do osteoclasts play in appositional growth and what is the purpose of this?
OC removes bone from the medullary cavity, ensuring that the cavity also gets wider and isn’t too dense (heavy and hard to move)
