Osteogenesis and the stages of bone development
The early stages of bone development.
Osteogenesis, also known as ossification, is the process in which bone forms. In the early stages, the ‘skeleton’ is made up of loose fibrous connective tissue membranes and hyaline cartilage, and are already in the shape of bones, these are the site where ossification will begin. This provides the foundation for subsequent ossification, starting in the 6th or 7th week of embryonic development. They will develop through one of two ways.
Intramembranous Ossification.
This is the development of embryonic connective tissue (mesenchyme) to flat bones such as the skull, and other bones such as the mandible, clavicle and maxilla. The steps of Intramembranous Ossification are as follows; …show more content…
The site at which bone develops. Mesenchymal cells group together and differentiate into osteogenic cells and then to osteoblasts.
Calcification.
Osteoblast cells in the ossification center secrete an organic matrix of bone and are surrounded by it. This secretion stops and the now osteocyte cells rest in lacunae and extend their cytoplasmic processes into canaliculi that spread in all directions. The matrix then hardens (calcifies) through the introduction of calcium and other mineral salts.
Formation of trabeculae.
While the bone matrix forms, it develops into trabeculae. These fuse together to form cancelous bone. Blood vessels then grow through the trabeculae, and along the surface of the newly formed bone, mesenchyme forms. Red bone marrows then develops from the connective tissue associated with the blood vessels.
Development of the periosteum.
Mesenchyme condenses and develops into the periosteum at the periphery of the bone. A layer of compact bone replaces the surface layers of the cancelous
The early stages of bone development.
Osteogenesis, also known as ossification, is the process in which bone forms. In the early stages, the ‘skeleton’ is made up of loose fibrous connective tissue membranes and hyaline cartilage, and are already in the shape of bones, these are the site where ossification will begin. This provides the foundation for subsequent ossification, starting in the 6th or 7th week of embryonic development. They will develop through one of two ways.
Intramembranous Ossification.
This is the development of embryonic connective tissue (mesenchyme) to flat bones such as the skull, and other bones such as the mandible, clavicle and maxilla. The steps of Intramembranous Ossification are as follows; …show more content…
The site at which bone develops. Mesenchymal cells group together and differentiate into osteogenic cells and then to osteoblasts.
Calcification.
Osteoblast cells in the ossification center secrete an organic matrix of bone and are surrounded by it. This secretion stops and the now osteocyte cells rest in lacunae and extend their cytoplasmic processes into canaliculi that spread in all directions. The matrix then hardens (calcifies) through the introduction of calcium and other mineral salts.
Formation of trabeculae.
While the bone matrix forms, it develops into trabeculae. These fuse together to form cancelous bone. Blood vessels then grow through the trabeculae, and along the surface of the newly formed bone, mesenchyme forms. Red bone marrows then develops from the connective tissue associated with the blood vessels.
Development of the periosteum.
Mesenchyme condenses and develops into the periosteum at the periphery of the bone. A layer of compact bone replaces the surface layers of the cancelous