Universidad Autonoma de Baja California. Unidad de ciencias de la salud. Presentacion con notas sobre osificacion intermembranal.

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4. M.O. = Matriz ósea
An ossification center appears in the fibrous connective tissue membrane. Selected
centrally located mesenchymal cells cluster and differentiate into osteoblasts,
forming an ossification center.
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6. Bone matrix (osteoid) is secreted within the fibrous membrane.
Osteoblasts begin to secrete osteoid, which is mineralized within a few days.
Trapped osteoblasts become osteocytes.
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8. Woven bone and periosteum form.
Accumuating osteoid is laid down between embryonic blood vessels, which
form a random network. The result is a network of trabeculae.
Vascularized mesenchyme condenses on the external face of the woven bone
and becomes the periosteum.
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12. Bone collar of compact bone forms and red marrow appears.
Trabecuae just deep to the periosteum thicken, forming a woven bone collar
that is later replaced with mature lamellar bone.
Spongy bone consisting of distinct trabeculae, persists internally and its
vascular tissue becomes red marrow.
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