Bone Ossification Flashcards
stimulates osteoclasts to degrade bone matrix and release Ca into blood
parathyroid hormone
in bone growth, ___ “run” & ___ “chase”
chondrocytes
osteoclasts
Identify A-F.
A. epiphysis
B. resting cartilage
C. proliferation
D. hypertrophy
E. calcification
F. ossification
forms mid-shaft (diaphysis). impedes diffusion to cells in center- acts as signal to calcify fetal hyaline cartilage
periosteal bone collar
Identify zones 1-5.
- Resting cartilage
- Proliferating cartilage
- Hypertrophic cartilage
- Calcified cartilage
- Ossification
Identify 1-3.
- hyaline cartilage
- bone collar
- periosteum
2 controls impacting bone remodeling?
Calcitonin/Parathyroid hormone
bone response to mechanical stress/gravity
stimulates calcium salt deposit in bone. inhibits osteoclasts.
calcitonin
calcified cartilage contains ___ collagen.
Bone contains __ collagen.
type 2
type 1
type of ossification?
intramembranous ossification
steps of endochondral ossification?
- fetal hyaline cartilage develops
- cartilage calcifies, periosteal bone collar forms
- primary ossification centers in diaphysis
- secondary ossification centers in epiphysis
- bone replaces cartilage
- epiphyseal plates ossify- form epiphyseal lines
Identify 1-5.
- mesenchyme
- osteoblast
- blood vessels
- osteoid
- osteocyte
in endochondral ossification, bone replaces cartilage everywhere except…
articular cartilage & epiphyseal plates
Identify zones 1-5.
(reverse)
- cartilage ossification
- cartilage calcification
- hypertrophic cartilage
- proliferation of cartilage
- resting cartilage
osteogenesis where bone cells differentiate directly from mesenchymal cells to produce osteoid- no precursor, nothing placed down ahead of this.
intramembranous ossification
calcitonin is released by the ___.
parathyroid hormone is released by the ___.
thyroid gland- parafollicular cells
parathyroid glands
as bone increases in diameter, what happens at periosteal layer? what happens at endosteal surface?
periosteal layer- osteoblasts secrete bone matrix (appositional growth- bones grow wider)
endosteum- osteoclasts break down matrix (to avoid bones becoming too heavy)
osteogenesis where mesenchyme is 1st replaced by hyaline cartilage, then bone model replaces the cartilage
endochondral ossification
steps of intramembranous ossification
1) ossification centers form from thickened regions of mesenchyme 2) osteoid undergoes calcification 3) woven bone forms 4) lamellar bone replaces woven bone (compact/spongy bone form)
