Glottis: functions and characteristics of this part of the body

The glottis is a hole located in the upper-middle part of the larynx, of variable size and narrow, which is delimited by the vocal cords, four folds of smooth muscle tissue that are located on each side of the space.

Beyond its technical terminological definition, today we are going to discover that the glottis, despite its nature anecdotal, it is an essential structure for the formation of sound: that is, human speech, among many others functions.

Although other living things can emit complex and developed sounds with different intentions (such as elephants, birds or primates), we are the only species that has generated a complex language, on which we have based our society and interactions on a daily basis. What would become of us without the laryngeal structures that give us the ability to diction?

Each small part of our body has an essential function for what today describes us both as a species and as autonomous individuals. Therefore, in this article we will see the functions and characteristics of the glottis.

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What is the glottis?

According to the Royal Spanish Academy of the Language (RAE), the glottis is defined as "hole or anterior opening of the larynx". Of course, this cold conglomeration of words does not do justice to the functionality and essential work of this space. Before entering fully into the structure that concerns us today, it is necessary to talk about the already named larynx, where it is found. Go for it.

The importance of the larynx

The larynx, defined as a tubular organ made up of nine pieces of cartilage, is a muscle-cartilaginous structure adapted to the phonation or voice emission needs of the human being. Due to its structural complexity (which would require a space by itself only to be described), we are going to divide the laryngeal structure into three parts in a simple way.

The subglottis or infraglottic level is the space below the vocal folds. At this level, the larynx joins the trachea. The glottic level (the glottis itself) is the triangular space that remains when the vocal folds are open. The supraglottis or the supraglottic level is the space located above the vocal folds, or what is the same, the laryngeal vestibule.

Once we have briefly described the morphology of this complicated tubular organ, we are going to limit ourselves to listing its multiple functions quickly:

• Protective: through its occlusion, the individual can swallow food without risk of it entering the upper respiratory tract.
• Respiration: mechanically and biochemically participates in the regulation of CO2 and the maintenance of acid-base balance.
• Respiratory fixation: it retains the air in the thorax when closing, which allows the realization of efforts and lifting of weights among other things.
• Swallowing: the elevation of the larynx favors the descent of the food bolus.
• Expectoration: defensive line against the entry of foreign substances into the body, as it allows their expulsion by coughing.
• Phonetic function: Of course, the gift of speech is an essential function for the larynx.
• Emotional communication: thanks to it we can produce sounds of sobbing, crying and grief.

These are some of the essential functions of the larynx, but we certainly haven't covered their entirety. Without any doubt, it is a multifaceted structure, since protects us from the entry of foreign substances or food into the upper respiratory tract but also allows us to communicate with each other and with the environment that surrounds us.

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Morphology and function of the glottis

Once the laryngeal function has been defined, let us return to the structure that concerns us here. The word "glottis" comes from the Latin "glossa", which means tongue. Only with the linguistic dissection of the term we can already guess where the shots are going to go.

From a physiological point of view, this space is defined as the middle part of the larynx, where the vocal cords meet. It should be noted that the anterior two thirds of the glottis make up the “ligamentous or membranous glottis”; while the posterior third makes up the "cartilaginous glottis".

To understand the space that separates the vocal cords, it is also necessary to describe them above. The vocal fold is formed thanks to the presence of a structure, called the vocal ligament, which runs from the ventral face of the arytenoid cartilage to the dorsal face of the thyroid cartilage and, on he, the vocal muscle and the laryngeal mucosa fall like a carp, which finally constitutes the membranous folds vowels.

It should be noted that between the lower vocal folds there is a hollow opening: the glottis. This space is in turn divided into two according to its functionality:

• Speaking glottis: space between the ligamentous edges of the vocal folds, located anteriorly.
• Respiratory glottis: portion that does not close during speech and allows the continuous passage of air.

As far as diction is concerned, without eager to enter into the production of sound due to the complexity that this process contains, we will limit ourselves to saying that sounds in which only the glottis is involved are called glottals. Many languages ​​on different continents present this glottal stop, that is, a voiceless consonant product of the interruption of the pulmonary air flow in the glottis.

Thus, we can conclude that the glottis has several functions: first, it allows the passage of air to the lungs (soon to be said), but in turn, this airflow makes the vocal cords vibrate, causing sounds. The phonating glottis space is essential for speech.

Finally, this portion of the laryngeal lumen also helps prevent the passage of food into the upper respiratory tract, especially at the time of swallowing. This last function is closely related to the structure above it, the epiglottis, which we reserve for another opportunity.

Diseases associated with this part of the body

Glottis cancer, also called laryngeal, throat, or vocal cord cancer, is one of the most serious diseases associated with this part of the body.. According to the American Cancer Society, the appearance of these tumor processes in the tissue surrounding the glottis cause hoarseness, dysphonia or changes in the voice, which allows its early detection in many cases.

Like most cancers associated with the neck and upper and lower respiratory tract, glottis cancer is positively correlated with tobacco use, and to a lesser extent, alcohol.

Despite this being the most relevant determining factor, there are genetic disorders that can promote glottic tumor formation, such as Falconi anemia or dyskeratosis congenita.

Finally, there are also gender and age biases: men are up to four times more likely to suffer from laryngeal cancer, and more than half of the patients are 65 years or older.

Another of the pathologies that affect the glottis is inflammation of your surrounding tissue from an allergic reaction, which makes the passage of air impossible and ends up causing the death of the patient by suffocation. This is a medical emergency, and if the inflammation does not resolve with the application of corticosteroids and other medications, a tracheostomy is necessary to allow air to pass into the lungs.

Resume

As we have seen, despite its morphological simplicity (since it is a gap, neither more nor less), the glottis is essential for both speech and respiration in humans and life itself. Different functions are collected in this space: from the passage of air to the lungs, passing through the protection of the superior ways to external agents and food, to the production of sounds and the miracle of speech in human beings humans.

This type of space highlights the exquisiteness of the human body: each small hole, each nook, each tissue and even each cell body has a specific and essential function for our organism. Of course, there is no doubt that our body is a true work of evolutionary engineering.

Bibliographic references:

Laryngeal and Hypopharyngeal Cancers, American Cancer Society. Picked up on September 17 in https://www.cancer.org/es/cancer/cancer-de-laringe-e-hipofaringe/causas-riesgos-prevencion/que-lo-causa.html. STADIUMS, T. C. TO. L. E., & II, I. CANCER OF THE GLOTIS. RESULTS OF. Glottis, Argentine Thorax Foundation (FAT). Picked up on September 17 in https://www.fundaciontorax.org.ar/page/index.php/pacientes/diccionario/1419-glotis. Glottis, National Cancer Institute (NIH). Picked up on September 17 in https://www.cancer.gov/espanol/publicaciones/diccionario/def/glotis. Larynx, ENT portal. Picked up on September 17 in https://sisbib.unmsm.edu.pe/bibvirtual/libros/medicina/cirugia/tomo_v/laringe.htm#:~:text=Tienen%20forma%20de%20pir%C3%A1mide%20triangular, the% 20m% C3% BAsculos% 20motors% 20del% 20cart% C3% ADlago. Torres, B., & Gimeno, F. (2008). Anatomy of the Voice. Paidotribo.