Numbering [edit]. Bus routes operating in or through Virginia are noted with a letter and a number. Bus routes operating in DC or Maryland use only a number, or a letter and a number, as noted below.
Cartilage: The three types of cartilage. There are three types of cartilage: 1  Hyaline-most common, found in the ribs, nose, larynx, trachea. 2  Is a precursor of bone. 3  Fibro-is found in invertebral discs, joint capsules, ligaments. 4  Elastic-is found in the external ear, epiglottis and larynx. Hyaline-most common, found in the ribs, nose, larynx, trachea. 2  Is a precursor of bone. 3  Fibro-is found in invertebral discs, joint capsules, ligaments. 4  Elastic-is found in the external ear, epiglottis and larynx.
Most of the cartilage that develops in prenatal life is eventually replaced by bone. However, there are two places where cartilage is found in the adult: Extraskeletal cartilage. For example, the cartilaginous rings in the trachea and the costal cartilage connecting ribs to the sternum. Articular cartilage. This type of cartilage is found in articulating joints, where it provides a smooth, gliding surface at the ends of articulating bones.