Cartilage, a tough and smooth elastic tissue, plays a crucial role in performing various essential functions within the body. It serves as a protective covering for the ends of long bones while also functioning as the primary structural component in body parts like the ears, nose, rib cage, and more. The human body consists of three types of cartilage: elastic, fibrous, and hyaline. However, unlike other types of tissue, cartilage has limited repair capabilities, making it susceptible to degeneration and damage. Consequently, this can lead to several side effects, with osteoarthritis being one of the most notable.
Structure of Cartilage
Cartilage is composed of two main components: water and matrix. In fact, approximately 85 percent of cartilage is made up of water, although this percentage tends to decrease as a person ages. The remaining 15 percent is comprised of the extracellular matrix. This matrix is a complex network of proteins, including collagen and proteoglycans, which play a crucial role in regulating various functions such as cell adhesion, cellular growth, and metabolism.
Collagen is responsible for providing cartilage with its tensile strength, while proteoglycans contribute to its elastic properties. In healthy cartilage, chondrocytes are the only cells present. These cells are responsible for the production and maintenance of the matrix. It is interesting to note that cartilage lacks a blood supply, nerves, or a lymphatic system.
Elastic Cartilage
Elastic cartilage, found in various regions of the human body, serves distinct yet comparable functions. Also known as yellow cartilage, it is characterized by the presence of numerous yellow elastic fibers embedded within its matrix. The chondrocytes are interspersed amidst this threadlike network of fibers. The abundance of elastic fibers grants this type of cartilage exceptional flexibility. Consequently, elastic cartilage can withstand bending forces while simultaneously providing support and maintaining shape. Notably, elastic cartilage plays a key role in the formation of external ear structures and the epiglottis, which is located in the throat.