No wonder the throat is called the "main gate" to the human body, because everything that gets inside passes through this organ. In the people it is often called simply "throat", but in medical terminology it has a different name. Let's find out what the functions of the pharynx are and what is its role in life processes.
Scientific definition
From a medical point of view, the pharynx (Latin pharynx) is the connecting circuit between the oral cavity and the nose. Outwardly, it looks like a tube that begins with the larynx and ends with the esophagus. This is the reason for its role as an important link not only in the digestive, but also in the respiratory process.
The structure of the pharynx
The anatomical structure of the pharynx is a complex scheme: this organ originates at the base of the skull (near the hyoid bone) and extends to the VI-VII cervical vertebrae (approximately at the level of the collarbones). The length of the human pharynx varies from 10 (in children and adolescents) to 14 cm (in adults).
The entire inner surface of the pharynx has a mucous membrane and glands, under which are hidden spherical muscles that can contract (compress and stretch). They are the ones who helpauthority to carry out its assigned tasks. The main functions of the pharynx:
- breath,
- swallowing food,
- voice education.
In general, the device of the pharynx can be described as follows: it consists of three sections (nasal, oral and laryngeal), each of which is connected by a common tube and performs certain actions. For a better understanding of the anatomy of the pharynx, the structure of each part of it should be studied in more detail.
Scheme of the nasopharynx
The upper part of the pharynx, connected to the nasal cavity, passes through special nasal openings - the choanae, and is called the nasopharynx. It consists of an anterior and a posterior part, thanks to which the two functions of the pharynx are performed. It is impossible to imagine a person without the process of breathing, which, in turn, will cease to function if any microprocess in the nasopharyngeal system is disturbed.
An important function of the nasopharynx is to protect our body from various microbes that can enter through the mouth opening. The fact is that in the back wall of the upper part of the pharynx there is a rather large accumulation of lymphadenoid tissue (in other words, these are tonsils), which is a kind of barrier to pathogenic bacteria and does not allow them to go deep.
Tonsils are located on the palatine arches, they are covered with stratified epithelium, which forms a dense protective wall against microbes. Lymphadenoid tissue is also located on the plane of the tongue, closer to the root itself. Together with the rest of the tonsils and follicles, theyform an annular chain in the thickness of the mucous membrane. In medical terminology, this part of the organ is called the pharyngeal lymphadenoid ring and is an essential part of the immune system.
The middle part of the pharynx: its structure and functions
The next part of the system can be considered the oropharynx: this area, which stretches from the root of the tongue to the esophagus. The entire surface of this tube is covered with a mucous membrane, under which the muscles are located. It is they who compress the pharynx and help push food into the esophagus. It's hard to believe, but all the muscles are in constant motion, thereby ensuring the vital activity of the pharyngeal cavity.
The largest muscles of the oropharynx are called constrictors, they have a large load during contraction of the muscular system. They are usually located in the back of the pterygoid process (the region of the root of the tongue) and perform the most important functions of the human pharynx in digestion. In addition to swallowing food and mucus, they are involved in the processes of opening and closing the pharynx. Depending on the location, they are divided into an upper constrictor, a middle constrictor, and two lateral constrictors.
Lower part of the pharynx - laryngopharynx
The lowest part of the organ is located in the back of the larynx, on the 4th vertebra, it stretches from the beginning of the larynx to the esophagus. The surface of the laryngopharynx has a fibrous membrane, under which are the longitudinal and transverse muscles. During a meal, the longitudinal muscle stretches and, as it were, lifts the pharynx, and the transverse muscles push through pieces of food. The role of the pharynx in digestion is largely determined by the state of the organ itself: how the tonsils work, are they able to protect against viral diseases, are there any developmental anomalies, and are there no chronic, traumatic or oncological diseases.
What are the functions of the pharynx in the respiratory system?
Everyone knows that two main elements of life are actually connected in the human throat: these are the respiratory and digestive systems. How is it that there are no collisions at this "crossroads" and that each process functions without failures? It's all about the cunning device of this body.
In the region of the nasopharynx, just above the level of the oral cavity, there is a small system of valves that alternately close or open one or another passage of the larynx, depending on the process (breathing or eating). The main air channel, which stretches from the nasopharynx to the larynx, is open when all the muscles are relaxed, so we can calmly inhale and exhale air through the mouth. When we yawn, the septum located in the region of the soft palate allows air to pass both into the oral and nasal cavities. Unfortunately, a person is not able to fully control the muscles of this septum: even if you raise the soft palate and stop the air flow, the passage will still remain open. This is the reason why sometimes food particles can get into the nasopharynx.
Next is the trachea, through which air enters from the beginning of the pharynx tothe lungs themselves. This organ largely contributes to the universal distribution of air flows in the pharynx, and thanks to the valve (epiglottis) located at its base, the main functions of the pharynx in the respiratory system are performed.
Main functions of the pharynx in digestion
The pharynx is the organ by which food enters the esophagus and then the stomach. In the pharynx, the most important processes take place that affect all further digestion. This is where food is first judged by taste: in the oropharynx, on the surface of the tongue, there are receptors that form the taste sensations from food and largely contribute to appetite.
Another function of the pharynx is the initial mechanical processing of food: with the help of teeth, we bite off food, chew it and grind it. An active salivation process takes place in the pharynx, due to which the food is moistened and easily passes through the entire larynx to the esophagus.
An interesting fact: the contraction of the muscles that contribute to the swallowing of food occurs reflexively, impulses come from the central nervous system that make the muscles move arbitrarily, that is, the person does not control this process. This feature of the pharynx was discovered when the person was under anesthesia.
Throat diseases
With the onset of cold weather, wholesale epidemics begin when people catch various viruses. One of the most susceptible to viral diseasesorgans is precisely the pharynx. The most common types of ailments are tonsillitis, pharyngitis, laryngitis, tonsillitis, etc. The symptoms of these diseases are very unpleasant: constant sore throat, runny nose or swollen tonsils. It is better not to postpone the treatment of the pharynx, timely therapy with the help of modern antibiotics will quickly get rid of a bacterial disease, and antiviral drugs effectively fight viruses. For prevention purposes, it is recommended to follow certain rules, for example, wear a mask in crowded places. Folk methods of treatment will not interfere either: warm milk with honey will surely soothe the mucous membrane of the larynx, and tincture of chamomile and herbs will strengthen the immune system.
