If a piece of food is particularly large, it could become trapped in the trachea and obstruct breathing. The primary function of the trachea is to transport air to and from the lungs. Without a trachea, a person would not be able to breathe.
In addition to transporting air, the trachea helps defend against disease. The mucus in the trachea helps capture microorganisms such as viruses and harmful bacteria before they enter the lungs.
On cold days, the trachea helps warm and provide humidity to the air before it reaches the lungs. Various health conditions can affect the trachea.
In serious cases, a person may have trouble breathing and require immediate medical attention. If coughing or shortness of breath is a persistent concern without a clear cause, speak with a doctor. It also helps prevent microorganisms, debris, and air that is too cold or too hot from entering the lungs. If a person is having trouble breathing, a health problem may be affecting their trachea, and they should seek medical attention as soon as possible. People can experience difficulty breathing for a wide range of reasons.
Histology of the Trachea : A cross section of the trachea, showing the hyaline cartilage, mucus glands, and ciliated epithelium. The cartilage of the trachea is considered hyaline cartilage: simple, transparent, and made primarily of collagen.
The trachealis muscle connects the open ends of the C-shaped rings of cartilage and contracts during coughing, reducing the size of the lumen of the trachea to increase the air flow rate. The esophagus lies behind the trachea. The C-shaped cartilaginous rings allow the trachea to collapse slightly at its opening, so food can pass down the esophagus after swallowing. The epiglottis closes the opening to the larynx during swallowing to prevent swallowed matter from entering the trachea.
This mucus and cilia of the trachea form the mucociliary escalator, which lines the cells of the trachea with mucus to trap inhaled foreign particles. The cilia then waft upward toward the larynx and the pharynx, where it can be either swallowed into the stomach and destroyed by acid or expelled as phlegm. The mucociliary escalator is one of the most important functions of the trachea and is also considered a barrier component of the immune system due its role in preventing pathogens from entering the lungs.
The epithelium and the mucociliary ladder can be damaged by smoking tobacco and alcohol consumption, which can make pneumonia an infection of the alveoli of the lungs from bacteria in the upper respiratory tract more likely to occur due to the loss of barrier function. The bronchi continue to divide, very much like the branches of a tree, into smaller and smaller tubes.
The tubes of each division contain a little less cartilage and a little more smooth muscle until eventually becoming tiny tubes containing only rings of smooth muscle - the terminal bronchioles, small structures less than 1mm in diameter. Because these tubes contain only muscle, they can be dilated as the muscle relaxes and constricted if the muscle contracts.
Bronchodilation occurs in response to stimulation of the sympathetic nervous system for example during exercise or to drugs such as adrenaline, noradrenaline and salbutamol. Bronchoconstriction occurs in response to parasympathetic nervous activity, acetylcholine, histamine and stimulation of receptors in the trachea and large bronchi by irritants such as smoke. Asthma is an exaggerated bronchoconstriction response to many physical, chemical and pharmacological agents Law and Watson, The terminal bronchioles further subdivide into an area called the respiratory exchange zone, minute tubes called respiratory bronchioles.
These lead to alveolar ducts, which look like the stems on a bunch of grapes. Each of these ducts ends in several alveolar sacs, resembling small clusters of grapes, and the wall of each alveolar sac is made up of cup-shaped alveoli. As there is no cartilage in the walls of these structures, they are all liable to collapse. Alveoli have very thin walls far thinner than a sheet of tissue paper and are surrounded by a rich network of blood vessels Fig 2. There are no cilia or mucus-producing cells in the alveolar epithelium - instead, the surface of the respiratory membrane inside the alveoli is covered with surfactant, a substance secreted by cuboidal cells within the membrane.
The incomplete cartilage rings of the trachea allow it to narrow and permit the esophagus to expand into its space. Finally, the loose connection of the adventitia allows the trachea to move within the neck and thorax, aiding the lungs in their expansion and contraction during breathing. By: Tim Taylor. Last Updated: Oct 23,
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