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(10 cards)
How do osteoblasts contribute to bone formation?
They help with the deposition of the inorganic components of bone
Where are active osteoblasts located?
at the surfaces of the bone matrix bound by integrins
What is osteoid?
A layer collagen-rich material produced by osteoblasts between the osteoblast layer and the preexisting bone surface
How does osteoid stain compared to mature mineralized matrix?
Osteoid stains lightly compared with the mature mineralized matrix
How do osteoblasts communicate with adjacent osteocytes?
Through thin cytoplasmic processes joined by gap junctions
What happens to osteoblasts after their synthetic activity is completed?
Some differentiate into osteocytes some become bone lining cells and the majority undergo apoptosis
What happens to osteoblasts that become surrounded by the material they secrete?
They differentiate into osteocytes enclosed in lacunae extending long dendritic processes
What are the characteristics of osteocytes compared to osteoblasts?
Osteocytes are the most abundant cells in bone but have significantly less rough endoplasmic reticulum (RER) smaller Golgi complexes and more condensed nuclear chromatin than osteoblasts
How do osteocytes communicate with each other and with other cells?
Via gap junctions
What is the function of osteocytes and what network do they use to carry out this function?
They are mechanosensors that detect the mechanical load on the bone and use the extensive lacunar-canalicular network
