Cartilage is a connective tissue. The cells, called chondrocytes (mature cartilage cells), make the matrix and fibers of the tissue. Chondrocytes are found in spaces within the tissue called "lacunae. "A cartilage with few collagen and elastic fibers is hyaline cartilage. The lacunae are randomly scattered throughout the tissue and the matrix takes on a milky or scrubbed appearance with routine stains . Sharks have cartilaginous skeletons, as does nearly the entire human skeleton during some pre-birth developmental stages. A remnant of this cartilage persists in the outer portion of the human nose. Hyaline cartilage is also found at the ends of long bones, reducing friction and cushioning the articulations of these bones.  Hyaline cartilage . Elastic cartilage has a large amount of elastic fibers, giving it tremendous flexibility. The ears of most vertebrate animals contain this cartilage, as do portions of <span class="_wysihtml5-temp-placeholder"></span>the larynx, or voice box. In contrast, fibrocartilage contains a large amount of collagen fibers, giving the tissue tremendous strength. Fibrocartilage comprises the intervertebraldiscs in vertebrate animals, which must withstand a tremendous amount of stress. Cartilage can also transform from one type to another. For example, hyaline cartilage found in movable joints, such as the knee and shoulder, often becomes damaged as a result of age or trauma. Damaged hyaline cartilage is replaced by fibrocartilage, resulting in "stiff" joints.