It is not surprising that the pharynx is called the "main gate" to the human body, because everything that enters passes through this organ. People often call it simply "throat", but in medical terminology it has a different name. Let's find out what are the functions of the pharynx and what is its role in the processes of life.
Scientific definition
From the point of view of medicine, the pharynx (from lat. Pharynx) is a connecting chain 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 what determines its role as the most important link not only in the digestive, but also in the respiratory process.
Pharyngeal structure
The anatomical structure of the pharynx is a difficult 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 clavicle). The length of the pharynx in humans 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 (contract and stretch). They help the body to fulfill the tasks assigned to it. The main functions of the pharynx:
- breathing
- swallowing food
- voice formation.
In general, the pharynx device can be described as follows: it consists of three departments (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 - choans, and is called the nasopharynx. It consists of front and back parts, thanks to which two functions of the pharynx are performed. It is impossible to imagine a person without a breathing process, which, in turn, will cease to function if any microprocess in the nasopharynx system is disrupted.
An important function of the nasopharynx is to protect our body from various microbes that can penetrate through the mouth. 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, tonsils), which is a kind of obstacle to pathogenic bacteria and does not allow them to go deeper.
Tonsils are located on the palatine arches, they are covered with a multilayer 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 remaining tonsils and follicles, they form a ring-shaped 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. They compress the throat 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 the compression of the muscular system. They are usually located in the back of the pterygoid process (the area 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 participate in the processes of opening and closing the pharynx. Depending on the location, they are divided into the upper constrictor, middle and two lateral.
The lower part of the pharynx is the larynx
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 larynxopharynx has a fibrous membrane, under which there are longitudinal and transverse muscles. During meals, the longitudinal muscle stretches and, as it were, raises the throat, while the transverse muscles push pieces of food. The role of the pharynx in digestion is largely determined by the state of the organ itself: how the tonsils work, whether they can protect against viral diseases, whether there are abnormalities in development and whether chronic, traumatic or oncological diseases are absent.
What are the functions of the pharynx in the respiratory system?
Everyone knows that in the human throat two main elements of vital activity are actually connected: these are the respiratory and digestive systems. How is it that there are no collisions at this "crossroads", and each process functions without failures? It's all about the cunning device of this body.
In the area 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 muscles are relaxed, so we can calmly inhale and exhale air through our mouths. When we yawn, the septum located in the region of the soft palate allows air to pass into both the oral and nasal cavities. Unfortunately, a person is not able to fully control the muscles of this septum: even if you lift the soft palate and stop the air flow, the passage will still remain open. This is precisely the reason why sometimes food particles can enter the nasopharynx.
Next is the trachea, through which air flows from the beginning of the pharynx to the lungs themselves. This organ largely contributes to the universal distribution of air flow in the pharynx, and thanks to the valve located at its base (epiglottis), the main functions of the pharynx in the respiratory system are performed.
The main functions of the pharynx in digestion
The pharynx is the organ through which the food ingested passes into the esophagus and then into the stomach. In the throat are the most important processes that affect all further digestion. It is here that food is first evaluated by taste: in the oropharynx, on the surface of the tongue, receptors are located that form the taste of food and in many ways 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 and grind it. In the throat, an active salivary process occurs, due to which the food is moisturized and easily passes through the larynx to the esophagus.
An interesting fact: the contraction of the muscles that facilitate swallowing food occurs reflexively, impulses come from the central nervous system that cause the muscles to move arbitrarily, that is, the person does not control this process. This feature of the pharynx was discovered when a person was in anesthesia.
Pharyngeal diseases
With the onset of cold weather, epidemics begin when people pick up various viruses. One of the organs most susceptible to viral diseases 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 eliminate the bacterial ailment, and antiviral drugs effectively fight viruses. In order to prevent, it is recommended to follow certain rules, for example, wear a mask in crowded places. Alternative methods of treatment will also not hurt: warm milk with honey will certainly soothe the larynx, and tincture of chamomile and herbs will strengthen the immune system.