trachea - Vertebrate Trachea, Invertebrate Trachea, Additional images

A tube connecting the larynx with the principal bronchi; also known as the windpipe. Lined by respiratory (columnar ciliated) epithelium, it has an external fibrous membrane which encloses hoops of cartilage (open at the back) that prevent the trachea from collapsing. During breathing the trachea stretches longitudinally (up to 2 cm/0·8 in). In the human adult it is 9–15 cm/3·5–6 in long. In cases of respiratory distress the trachea can be surgically opened between the cartilage rings within the lower part of the neck to provide a passage for air (tracheostomy).

Trachea (IPA: ['treikiə]) is a common biological term for an airway through which respiratory air transport takes place in organisms. In terrestrial vertebrates, such as birds and humans, the trachea lets air move from the throat to the lungs. In terrestrial invertebrates, such as onychophorans and insects, tracheae conduct air from outside the organism directly to all internal tissues.

Vertebrate Trachea

The trachea, or windpipe, is a tube extending from the larynx to the bronchi in mammals, and from the pharynx to the syrinx in birds, carrying air to the lungs.

In ill or injured persons, the natural airway formed by the trachea may be damaged or closed off. Endotracheal Intubation is the medical procedure of inserting an artificial tube into the trachea to permit breathing. Tracheotomy is a surgical procedure of making an opening in the front of the neck that extends to the lumen of the trachea, a short tube called a tracheostomy tube is inserted through this opening, entering below the level of the larynx and vocal cords.

Diseases of the trachea include:

Tracheobronchitis Tracheomalacia Tracheal fracture Airway obstruction Malignancy Tracheal collapse

Invertebrate Trachea

Many terrestrial arthropods have evolved a closed respiratory system composed of spiracles, tracheae, and tracheoles to transport metabolic gasses to and from tissue.

A tracheal tube may contain ridge-like circumferential rings of taenidia in various geometries such as loops or helices.

In the head, thorax, or abdomen, tracheae may also be connected to air sacs. In some aquatic insects, the tracheae exchange gas through the body wall directly, in the form of a gill.

Additional images

Section of the neck at about the level of the sixth cervical vertebra.

Transverse section of trachea.

Thyroid

Respiratory system