You can mark you interesting snippets of text that will be available through a unique link in your browser.


cartilage

Translation
cartilage
/kahr"tl ij, kahrt"lij/, n. Anat., Zool.
1. a firm, elastic, flexible type of connective tissue of a translucent whitish or yellowish color; gristle.
2. a part or structure composed of cartilage.
[1350-1400; ME ( < MF) < L cartilago gristle]

* * *

Connective tissue in parts of the human skeleton.

A network of collagen fibres in a firm, gelatinous base, it contains no blood vessels or nerves. Different types of cartilage are found at the ends of some bones and in nasal and respiratory structures; in the spinal disks; and in the ear and epiglottis (back of the throat). Most of the skeleton of an embryo is made of cartilage, which is later replaced by bone.

* * *

       connective tissue forming the skeleton of mammalian embryos before bone formation begins and persisting in parts of the human skeleton (skeletal system, human) into adulthood. Cartilage is the only component of the skeletons of certain primitive vertebrates, including lampreys (lamprey) and sharks (shark). It is composed of a dense network of collagen fibres embedded in a firm, gelatinous ground substance that has the consistency of plastic; this structure gives the tissue tensile strength, enabling it to bear weight while retaining greater flexibility than bone. Cartilage cells, called chondrocytes, occur at scattered sites through the cartilage and receive nutrition by diffusion through the gel; cartilage contains no blood vessels or nerves, unlike bone.

      Three main types of cartilage can be distinguished. Hyaline cartilage is the most widespread and is the type that makes up the embryonic skeleton. It persists in human adults at the ends of bones in free-moving joints as articular cartilage, at the ends of the ribs, and in the nose, larynx, trachea, and bronchi. It is a glossy blue-white in appearance and very resilient. Fibrocartilage is the tough, very strong tissue found predominantly in the intervertebral disks and at the insertions of ligaments (ligament) and tendons (tendon); it is similar to other fibrous tissues but contains cartilage ground substance and chondrocytes. Elastic cartilage, which is yellow in appearance, is more pliable than the other two forms because it contains elastic fibres in addition to collagen. In humans it makes up the external ear (ear, human), the auditory tube of the middle ear, and the epiglottis.

      A major role of cartilage in humans is to form a model for later growth of the bony skeleton. The clavicle, or collarbone, and some parts of the skull are not preformed in cartilage. In the embryo, cartilage gradually calcifies, and chondrocytes are replaced by bone cells, or osteocytes. After birth a thin plate of cartilage, called the epiphyseal plate, persists at the ends of growing bones, finally becoming ossified itself only when the bone behind it has completed its growth. At the growing edge of the plate, chondrocytes continue to grow and divide, while on the trailing edge they are replaced by osteocytes as new bone is laid down. The cartilage plate thus remains of a constant thickness while the bone grows behind it. Once this plate disappears, no further longitudinal bone growth is possible.

* * *


Universalium. 2010.

Synonyms:

  
Share  

Look at other dictionaries:

  • Cartilage — Hyaline cartilage showing chondrocytes and organelles, lacunae and matrix Cartilage …   Wikipedia

  • Cartilage — observé au microscope photonique Le cartilage est un tissu conjonctif spécialisé formé par des cellules de forme arrondie, les chondrocytes, incluses dans des logettes nommées chondroplastes au sein d une matrice extracellulaire constituée de… …   Wikipédia en Français

  • CARTILAGE — Tissu de soutien d’origine mésenchymateuse dont la différenciation dépend étroitement de la mise en jeu de facteurs mécaniques (pressions et frottements), le cartilage comprend des cellules appelées chondrocytes, de forme arrondie. Leur… …   Encyclopédie Universelle

  • Cartilage — Car ti*lage, n. [L. cartilago; cf. F. cartilage.] (Anat.) A translucent, elastic tissue; gristle. [1913 Webster] Note: Cartilage contains no vessels, and consists of a homogeneous, intercellular matrix, in which there are numerous minute cavities …   The Collaborative International Dictionary of English

  • cartilage — noun хрящ …   Англо-русский словарь Мюллера

  • cartilage — 1> хрящ …   Новый большой англо-русский словарь

  • CARTILAGE — s. m. T. d Anat. Partie blanche, dure, lisse, élastique, privée de sentiment, qui se trouve surtout aux extrémités des os, et qu on appelle vulgairement le croquant dans la viande de boucherie. Le cartilage du nez. Le cartilage des oreilles …   Dictionnaire de l'Academie Francaise, 7eme edition (1835)

  • CARTILAGE — n. m. T. d’Anatomie Partie blanche, dure, lisse, élastique, qui se trouve surtout aux extrémités des os. Le cartilage du nez. Le cartilage des oreilles …   Dictionnaire de l'Academie Francaise, 8eme edition (1935)

  • cartilage — Connective tissue dominated by extracellular matrix containing collagen type II and large amounts of proteoglycan, particularly chondroitin sulphate. Cartilage is more flexible and compressible than bone and often serves as an early skeletal… …   Dictionary of molecular biology

  • cartilage — ˈkɑ:tɪlɪdʒ сущ. хрящ хрящ cartilage хрящ …   Большой англо-русский и русско-английский словарь