THE BASIC STRUCTURE OF BONES - 1
Bones are made of a type of connective tissue formed by specialized resident cells derived from the mesenchyme and by a hard, mineralized extracellular matrix.
The bone extracellular matrix is quite unique, as it is formed by an organic portion and a mineralized portion. It has the following main features:
- A predominance of type I collagen fibers in the organic matrix.
- The organic portion of the extracellular matrix contains also proteoglycans and glycoproteins, some of which are exclusive to or characteristic of bones.
- The inorganic matrix is calcified as because of the deposition of calcium phosphate on the collagen fibrils that results in the production of hydroxyapatite crystals.
As collagen fibers stain well with eosin, the bone matrix appears pink after staining bone sections with H&E, unlike the cartilaginous matrix that stains bluish/blue by hematoxylin.
Histological sections of bones and teeth
Hard tissues require special methodologies to obtain histological sections. Click on the links to examine them Peparation of hard tissues – bone and teeth – 1 and Peparation of hard tissues – bone and teeth – 2