HE stain was used to evaluate the healing degree of fracture according to the proportion of fibroblast, chondroblast, woven bone tissues and mature bone tissues. There were 10 grades all together.
The trachea is kept open by 15-20 incomplete C-shaped rings of cartilage separated by fibrous connective tissue that stiffens the front and sides of the tube.
So, the structural classification of your bones is all about what kind of material binds those bones together — like, is it a fibrous tissue or cartilage, or a special fluid-filled joint cavity.