Interesting Facts About Larynx: The “Voice Box”

Larynx is the ‘voicebox’, the organ in the neck that plays a crucial role in speech and breathing. The channels for air and for food, which share the pharynx at the back of the nose and mouth, diverge at this point, leading respectively to the trachea and to the oesophagus. The opening for air through the larynx is known as the glottis, and the epiglottis, below and behind the tongue, plays a necessary part in closing off the glottis during swallowing.
The larynx has three important functions: control of the airflow during breathing, protection of the airway below it, and production of sound for speech. The main part of the framework of the larynx is the thyroid cartilage, and it is the front part of this that can easily be seen and felt as the ‘Adam’s apple’.
The area around the larynx contains lymph nodes. These are also called lymph glands. They are small bean shaped glands. They are part of the lymphatic system which runs throughout the body. The lymphatic system is filled with fluid called lymphatic fluid. The lymph glands help to control infection by filtering anything foreign to the body out in the lymphatic fluid. This includes bacteria and viruses.
Below are some interesting facts about Larynx:
1. In the larynx are folds of tissue called the ventricular folds. Two pairs contain the false and true vocal cords. The true cords plus the cartilages and ligaments help produce sound. Nerve impulses help control the vocal cords to make different sounds.
2. The larynx grows as the body grows. The largest growth is during puberty, particularly in boys. The boy’s larynx grows so fast that the Adam’s apple becomes very prominent, and he is unable to control his vocal cords. As the vocal cords become thicker and longer the voice becomes deeper in quality and pitch.
3. The larynx is composed of an external skeleton of cartilage plates that prevents collapse of the structure. The plates are fastened together by membranes and muscle fibres. The front set of plates, called thyroid cartilage, has a central ridge and elevation commonly known as the Adam’s apple. The plates tend to be replaced by bone cells beginning from about 20 years of age onward.
4. Sounds are produced in the larynx by the movement of air through the larynx and by the vocal folds, a pair of movable folds in the mucous membrane. The vocal folds are connected to the thyroid cartilage on their anterior ends and the arytenoid cartilages on their posterior end. Air exhaled from the lungs passes through the larynx and vibrates the vocal folds. Several sets of muscles move the arytenoid cartilages and the cricothyroid joint to adjust the position and tension of the vocal folds and thereby control the pitch of sound made by the larynx.
5. The muscles of the larynx are divided into intrinsic and extrinsic muscles. The intrinsic muscles are divided into respiratory and the phonatory muscles (the muscles of phonation). The respiratory muscles move the vocal cords apart and serve breathing. The phonatory muscles move the vocal cords together and serve the production of voice.
The extrinsic, passing between the larynx and parts around; and intrinsic, confined entirely. The main respiratory muscles are the posterior cricoarytenoid muscles. The phonatory muscles are divided into adductors (lateral cricoarytenoid muscles, arytenoid muscles) and tensors (cricothyroid muscles, thyroarytenoid muscles).
6. In adult humans, the larynx is found in the anterior neck at the level of the C3–C6 vertebrae. In newborn infants, the larynx is initially at the level of the C2–C3 vertebrae, and is further forward and higher relative to its position in the adult body. The larynx descends as the child grows.
7. Pioneering work on the structure and evolution of the larynx was carried out in the 1920s by the British comparative anatomist Victor Negus, culminating in his monumental work The Mechanism of the Larynx (1929).
Negus, however, pointed out that the descent of the larynx reflected the reshaping and descent of the human tongue into the pharynx. This process is not complete until age six to eight years.

Leave a Reply, No Login Necessary.