Cartilage is a type of dense connective tissue. It is composed of collagen fibers and/or elastin fibers, and can supply smooth surfaces for the movement of articulating bones. Cartilage is found in many places in the body including the joints, the rib cage, the ear, the nose, the bronchial tubes and the intervertebral discs. There are three main types of cartilage: elastic, hyaline, and fibrocartilage. Connective tissue is one of the four types of tissue in traditional classifications (the others being epithelial, muscle, and nervous tissue. ... Tropocollagen triple helix. ... Elastin, also known as elasticin, is a protein in connective tissue that is elastic and allows skin to return to its original position when it is poked or pinched. ... This article is about the bones called ribs. ... For other uses, see Ear (disambiguation). ... For other uses, see Nose (disambiguation). ... A bronchus (plural bronchi, adjective bronchial) is a caliber of airways in the the respiratory tract that conducts air into the lungs. ... Intervertebral discs lie in between adjacent vertebrae in the spine. ...

Types of cartilage

There are three different types of cartilage, each with special characteristics adapted to their function.

Elastic cartilage

Elastic cartilage (also called yellow cartilage) is found in the pinna of the ear and several tubes, such as the walls of the auditory (Eustachian) tubes and larynx and especially in the epiglottis. Cartilage is present to keep the tubes permanently open. Elastic cartilage is similar to hyaline cartilage but contains elastic bundles (elastin) scattered throughout the matrix. This provides a tissue which is stiff yet elastic. Elastic cartilage is a type of cartilage present in the outer ear, larynx, and epiglottis which contains fibers made of elastin. ... The pinna (Latin for feather) is the visible part of the ear that resides outside of the head (this may also be referred to as the auricle or auricula). ... The Eustachian tube (or auditory tube) is a tube that links the pharynx to the middle ear. ... The larynx (plural larynges), colloquially known as the voicebox, is an organ in the neck of mammals involved in protection of the trachea and sound production. ... Elastin, also known as elasticin, is a protein in connective tissue that is elastic and allows skin to return to its original position when it is poked or pinched. ...

Hyaline cartilage

Hyaline cartilage is found in the nose, thyroid and it connects the ribs to the sternum. It is also required in the Endochondral development of bone. It has fibers scattered throughout its matrix, which looks glassy. Chondrocytes are found in the lacunae. Cartilage is type of dense connective tissue. ... Chondrocytes are the cells of cartilage. ...

Fibrocartilage

Fibrocartilage is found in between the vertebrae of the spinal column. It is very fibrous. Cartilage is type of dense connective tissue. ...

Growth and development

Cartilage in fetal development

In embryogenesis, most of the skeletal system is derived from the mesoderm germ layer. Chondrification (also known as chondrogenesis) is the process in which cartilage is formed from condensed mesenchyme tissue, which differentiates into chondrocytes and begins secreting the materials that form the matrix. Embryogenesis is the process by which the embryo is formed and develops. ... Skeleton is also a winter sport: see skeleton (sport). ... Organs derived from each germ layer. ... Mesenchyme (also known as embryonic connective tissue) is the mass of tissue that develops mainly from the mesoderm (the middle layer of the trilaminar germ disc) of an embryo. ... Chondrocytes are the cells of cartilage. ...

Early in fetal development, the greater part of the skeleton is cartilaginous. As this cartilage is afterward replaced by bone, it is called temporary. In contrast, the cartilage in the joints remains unossified during the whole of life, and is called permanent. Ossification is the process of bone formation, in which connective tissues, such as cartilage are turned to bone or bone-like tissue. ...

Mineralisation

Adult hyaline articular cartilage is progressively mineralised at the junction between cartilage and bone. It is then termed articular calcified cartilage. A mineralisation front advances through the base of the hyaline articular cartilage at a rate dependent on cartilage load and shear stress. Intermittent variations in the rate of advance and mineral deposition density of the mineralising front, lead to multiple tidemarks in the articular calcified cartilage.

Adult articular calcified cartilage is penetrated by vascular buds, and new bone produced in the vascular space in a process similar to endochondral ossification at the physis. A cement line demarcates articular calcified cartilage from subchondral bone. Section of fetal bone of cat. ... This page is a candidate to be copied to Wiktionary using the Transwiki process. ...

Growth

Two types of growth can occur in cartilage: appositional and interstitial. Appositional growth results in the increase of the diameter or thickness of the cartilage. The new cells derive from the perichondrium and occur on the surface of the cartilage model. Interstitial growth results in an increase of cartilage mass and occurs from within. Chondrocytes undergo mitosis within their lacuna, but remain imprisoned in the matrix, which results in clusters of cells called isogenous groups.

Repair

Cartilage generally has very limited repair capabilities. Because chondrocytes are bound in lacunae, they cannot easily migrate to damaged areas and lay down new matrix. Damaged cartilage is usually replaced by fibrocartilage scar tissue.

Diseases / Medicine

There are several diseases which can affect the cartilage. Chondrodystrophies are a group of diseases characterized by disturbance of growth and subsequent ossification of cartilage. Some common diseases affecting/involving the cartilage are listed below. This article is about the skeletal organs. ...

• Arthritis: The cartilage covering bones in joints (articular cartilage) is degraded, resulting in movement limitation and pain.
• Achondroplasia: Reduced proliferation of chondrocytes in the epiphyseal plate of long bones results in a form of dwarfism.
• Costochondritis: Inflammation of cartilage in the ribs which causes chest pain
• Herniated disk: Asymmetrical compression of a disk ruptures the cartilage ring, causing tissue to herniate into the spinal canal.

The matrix of cartilage acts as a barrier, preventing the entry of lymphocytes or diffusion of immunoglobulins. This property allows for the transplantation of cartilage from one individual to another without fear of tissue rejection. Arthritis (from Greek arthro-, joint + -itis, inflammation; plural: arthritides) is a group of conditions where there is damage caused to the joints of the body. ... Circus Busch, 1906 Achondroplasia is a type of autosomal dominant genetic disorder that is a common cause of dwarfism. ... This article is about the medical condition. ... A disease invented by matt jadrnak to get out of school and use as a FAKE excuse. ... Look up hernia in Wiktionary, the free dictionary. ... Intervertebral discs lie in between adjacent vertebrae in the spine. ... The spinal canal is the space in vertebrae through which the spinal cord passes. ... A lymphocyte is a type of white blood cell involved in the human bodys immune system. ... Schematic of antibody binding to an antigen An antibody is a protein complex used by the immune system to identify and neutralize foreign objects like bacteria and viruses. ... “Transplant” redirects here. ...

Bioengineering techniques are being developed to generate new cartilage, using a cellular "scaffolding" material and cultured cells to grow artificial cartilage. Biological engineering (also biosystems engineering and bioengineering) deals with engineering biological processes in general. ...

Cartilage cells can give rise to benign (chondroma) tumors. Malignant chondrosarcomas are tumors of bone, not cartilage. A chondroma is a benign cartilaginous tumor, which is encapsulated with a lobular growing pattern. ... A chondrosarcoma is a cancer of the cartilage. ...

Invertebrate cartilage

Cartilage tissue can also be found among invertebrates such as horseshoe crabs, marine snails, and cephalopods. Binomial name Linnaeus, 1758 The horseshoe crab, horsefoot, king crab, or sauce-pan (Limulus polyphemus, formerly known as Limulus cyclops, Xiphosura americana, Polyphemus occidentalis) is a chelicerate arthropod. ... For other uses, see Snail (disambiguation). ... Orders Subclass Nautiloidea †Plectronocerida †Ellesmerocerida †Actinocerida †Pseudorthocerida †Endocerida †Tarphycerida †Oncocerida †Discosorida Nautilida †Orthocerida †Ascocerida †Bactritida Subclass †Ammonoidea †Goniatitida †Ceratitida †Ammonitida Subclass Coleoidea †Belemnoidea †Aulacocerida †Belemnitida †Hematitida †Phragmoteuthida Neocoleoidea (most living cephalopods) ?†Boletzkyida Sepiida Sepiolida Spirulida Teuthida Octopoda Vampyromorphida The cephalopods (Greek plural (kephalópoda); head-foot) are the mollusk class...

See also

• Biomechanics
• Chondroplasty
• Connective tissue
• Endochondral ossification
• Knee Cartilage Replacement Therapy
• Shark cartilage

Biomechanics is the research and analysis of the mechanics of living organisms or the application and derivation of engineering principles to and from biological systems. ... Chondroplasty refers to surgery of the thyroid chondroplasty (or trachea shave) is used to reduce the visibility of the Adams Apple in transsexual women. ... Connective tissue is one of the four types of tissue in traditional classifications (the others being epithelial, muscle, and nervous tissue. ... Section of fetal bone of cat. ... // Articular cartilage, most notably that which is found in the knee joint, is generally characterized by very low friction, high wear resistance, and poor regenerative qualities. ... Shark cartilage is a popular dietary supplement used to combat and/or prevent a variety of illnesses, most notably cancer. ...

External links

• University of Kansas Medical Center Cartilage tutorial
• Public domain text from Gray's anatomy dated 1918, so probably needs updating
• I've heard 'Ears and nose do not ever stop growing.' Is this false?