Function of the nasal cavity in humans

Posted on by admin

Nose - meaning and functions of the nose

The nose, as the initial section of the respiratory tract, through which all exhaled and inhaled air passes under normal conditions, is of great importance in the relationship of the body with the external environment.

Table of contents:

In the vestibule of the nasal cavity, all people have hair that plays a protective function. Therefore, boils often develop in the vestibule of the nasal cavity. A boil never occurs in the nasal cavity itself.

The nasal cavity is divided along the midline by the nasal septum. In its anterior sections, closer to the nostrils, the thickness of the mucous membrane superficially contains a network of blood vessels. With various vasculitis, rheumatism, infectious diseases, atherosclerosis and other diseases, blood vessels open and nosebleeds occur. These most frequently bleeding places in the nasal cavity are called Kiesselbach's zones, named after the author who described them.

In the nasal cavity in the area of ​​the choanae there is a massive venous plexus, from which significant bleeding can occur in various pathological conditions.

Functions of the nose

Being the initial section of the upper respiratory tract, the nasal cavity performs primarily the respiratory function. The amount of air that passes in an adult through both halves of the nasal cavity with a normal structure is 500 cm3 with one breath, and since a healthy person takes breaths in 1 minute, during this time about 9 liters of air pass through the nose.

The next function of the nose is protective, which consists of heating, humidifying and purifying the air from dust particles and microbial bodies. Warming of the air in the nasal cavity occurs due to the good vascularization of the mucous membrane and the presence of venous cavernous tissue in the area of ​​the nasal turbinates. The level of warming depends on the blood supply in the nasal mucous membrane. When inhaling cold air, the blood vessels reflexively dilate, the nasal turbinates increase in volume, and the nasal passages narrow.

This ensures closer contact of the inhaled air with the nasal mucosa and better warming of the air. The air is humidified by the evaporation of mucus, which is secreted by the goblet cells of the mucous membrane and is discharged into the nasal cavity through the nasolacrimal canal. Providing constant moisture to the nasal mucosa is essential for the function of the ciliated epithelium, the hairs of which are normally covered with a thin layer of mucus. For all these needs, the mucous membrane secretes about 0.5 liters of moisture per day.

Studies have shown that 40-60% of dust particles and bacteria in the air are retained in the nasal cavity. When breathing through the mouth, the entire mass of microbes and dust is sent to the lower respiratory tract, causing corresponding changes.

Along with the cleansing function, the bactericidal function should also be noted, which is manifested in the bacteriological effect of mucin and lysocin in nasal mucus.

The next function is resonator. The nose and its paranasal sinuses are the final section of the presented tube of the speech and vocal apparatus. A number of sounds, both vowels and consonants, are formed in the nasal cavity. In addition, the individual structural features of the nasal cavity and paranasal sinuses give the voice a certain individual timbre, individual sonority.

The olfactory function of the nose is caused by irritation by odorous substances of the peripheral part of the olfactory analyzer, embedded in the mucous membrane of the olfactory zone of the nasal cavity.

And last but not least is the cosmetic function of the nose. Look at the people around you and imagine them without a nose. In this case, a pleasant face will immediately turn into a repulsive mask in your mind. There is a special science - cosmetology, in which rhinoplasty occupies a large place.

Source: http://www.diagnos-online.ru/articles.php?page=16864

Nasal cavity

The nasal cavity is the beginning of the human respiratory tract. This is the air channel that connects the nasopharynx with the external environment. The nasal cavity houses the olfactory organs; in addition, the incoming air is warmed and purified here.

Structure of the nasal cavity

The outer side of the nose consists of the nostrils or wings, the middle part or back and the root, which is located in the frontal lobe of the face. The bones of the skull form its walls, and the palate limits it on the side of the mouth. The entire nasal cavity is divided into two nostrils, each of which has a lateral, medial, superior, inferior and posterior wall.

The nasal cavity is built with the help of bone, membranous and cartilaginous tissue. The whole of it is divided into three shells, but only the last of them is considered true, since it is formed by bone. Between the shells there are passages through which air passes; these are the top passage, the middle passage and the bottom passage.

On the inside of the cavity is the mucous membrane. The mucous membrane of the nasal cavity is thin and performs several functions at once: it cleans and warms the air, and also helps to distinguish odors.

Functions of the nasal cavity

The entire structure of the nasal cavity allows it to perform a number of specific functions. The main functions of the nasal cavity are:

  • respiratory function, which ensures the supply of oxygen to body tissues;
  • a protective function that guarantees cleaning from dust, dirt and harmful microorganisms, humidifying and warming the air using the nasal mucosa;
  • resonator function, which guarantees the imparting of sonority and individual coloring to the voice;
  • olfactory function, which allows you to distinguish different shades of aromas.

Diseases of the nasal cavity

There are quite a few diseases that can affect the nasal cavity. They are caused by a variety of reasons, for example, individual structural features of the organ, viruses and bacteria, and improper use of medications.

The most common diseases are:

  • vasomotor rhinitis, which is caused by a decrease in vascular tone from the submucosa of the lower conchae;
  • allergic rhinitis, which occurs due to an individual reaction to irritants;
  • hypertrophic rhinitis, which occurs as a result of other types of rhinitis and is characterized by an increase in connective tissue;
  • medicinal rhinitis develops due to improper use of medications;
  • adhesions after nasal injuries or surgical interventions;
  • polyps, which are growths of the nasal mucosa due to advanced rhinosinusitis;
  • neoplasms, which include osteomas, papillomas, fibromas, cysts.

Treatment of any diseases of the nose should be carried out immediately and professionally, since breathing problems can lead to disruptions in the functioning of almost all human organs.

Studies of the nose and paranasal sinuses

The examination of the nasal cavity is usually carried out in three stages. At the first stage, an external examination of the nose and examination of the projection sites of the paranasal sinuses on the face are carried out. The external nose, anterior and inferior walls of the frontal sinuses, anterior walls of the maxillary sinuses, submandibular and cervical lymph nodes are palpated.

At the second stage, rhinoscopy is performed, which can be anterior, middle and posterior. It is carried out using special lighting, for example, a frontal reflector or an autonomous light source. For a better examination, a nasal speculum is used - a nasal dilator. And at the last stage, the respiratory and olfactory functions of the nasal cavity are assessed.

When using materials from the site, the active reference is obligatory.

The information presented on our website should not be used for self-diagnosis and treatment and cannot serve as a substitute for consultation with a doctor. We warn you about the presence of contraindications. Specialist consultation is required.

Source: http://dolgojit.net/nosovaia-polost.php

Nasal cavity

The beginning of the respiratory tract in the body is the nasal cavity, which is an air channel that communicates with the external environment on one side and with the nasopharynx on the other. The olfactory receptors are located here, and the main tasks of the cavity are: protective, cleansing and moisturizing functions. The size of this depression increases with age - in an adult it is three times larger than in an infant.

Structure of the nasal cavity

Externally, the nose consists of wings, or nostrils, a dorsum - the middle part and a root located in the frontal lobe of the face. Inside, its walls are formed by the bones of the skull, and on the side of the mouth it is limited by the hard and soft palate. It has a complex structure - the nasal cavity is divided into two nostrils, each of which has a medial (septum between the nostrils), lateral, upper, lower and posterior walls.

In addition to bone tissue, the structure of the nasal cavity includes membranous and cartilaginous components, which are characterized by high mobility. There are three shells in the cavity - upper, middle and lower, but only the last one is true, since one of it is formed by an independent bone. Between the shells there are passages - spaces through which air flows pass:

  • top stroke. It is located posteriorly and has holes in the ethmoid bone cell;
  • average stroke. It communicates with its anterior cells, with the frontal and maxillary sinuses;
  • bottom stroke. It connects through the nasolacrimal duct to the orbit.

The mucous membrane in the nose is very thin and has several lobes - the respiratory one, which helps in processing air, and the smaller olfactory one, which helps in the perception of odors. The first contains many cilia that remove dirt and mucous glands that help fight pathogenic bacteria. The underlying base includes nerve and vascular plexuses - they help warm the air.

It is interesting that the two parts of the nasal cavity are not exactly the same, since the septum separating them in most cases is slightly shifted to one side.

Functions of the nasal cavity

The human nasal cavity performs a wide variety of functions, since it plays an important role in the interaction of the body with the outside world. Scientists have proven that proper nasal breathing promotes the correct functioning of all internal organs. The primary purposes of the nose include:

  • respiratory function. Provides oxygen supply to tissues, which is necessary for flawless functioning;
  • protective function. The inhaled air comes into contact with the mucous membrane and due to this, a number of significant transformations occur - release from harmful impurities and dust, disinfection, humidification and thermoregulation;
  • resonator function. The cavities of the nose, pharynx and paranasal sinuses are air resonators of the voice, which give it sonority, individual coloring and tonality. With diseases that occur in this area, the voice becomes nasal and dull;
  • olfactory function. Quite significant, primarily in a number of professions related to the perfume, food and chemical industries. The influence of odor perception on the reflex secretion of digestive juices and saliva has been proven.

Diseases of the nasal cavity

Numerous factors lead to diseases of the nasal cavity - individual structural features, dysfunction of various organs and many other reasons. The main diseases include:

  • vasomotor rhinitis. The basis of the disease is a decrease in the tone of blood vessels located in the submucosa of the lower conchae;
  • allergic rhinitis. The cause of a variety of disease is an individual reaction to an irritant - pollen, fluff, dust;
  • hypertrophic rhinitis. It appears as a result of other types of chronic rhinitis and is characterized by an increase in connective tissue;
  • drug-induced rhinitis. This type of breathing problem occurs due to long-term use of vasoconstrictor medications;
  • synechiae. Adhesions, or synechiae, occur as a result of trauma to the nose or after surgery;
  • polyps. The form of advanced rhinosinusitis is an overgrowth of the mucous membrane and is often accompanied by allergic rhinitis;
  • neoplasms. These include papillomas, fibromas, osteomas, and cysts.

N photo - the nasal cavity - it has a complex structure and at the same time enormous functional significance. This part allows the entire body to be properly saturated with oxygen, protects against pathogenic bacteria, and promotes the ability to perceive odors. Dysfunction can lead to malfunction of many human organs, so treatment of emerging diseases should be carried out under the strict supervision of a doctor.

only to be carried out by a doctor!

  • About the disease
    • Sinusitis
    • Varieties
    • Sinusitis
    • Rhinosinusitis
    • Frontit
  • About symptoms
    • Runny nose
    • Snot
  • About procedures
  • Other...
    • About drugs
    • Library
    • News
    • Questions for the doctor

Copying of materials is permitted only with indication of the original source

Nasal cavity

Brief characteristics of the nasal cavity

The nasal cavity is the cavity that is the beginning of the human respiratory tract. It is an air channel that communicates in front with the external environment (through the openings of the nose), and in the back with the nasopharynx. The olfactory organs are located in the nasal cavity, and the main functions are warming, clearing foreign particles and humidifying the incoming air.

Structure of the nasal cavity

The walls of the nasal cavity are formed by the bones of the skull: ethmoid, frontal, lacrimal, sphenoid, nasal, palatine and maxillary. The nasal cavity is separated from the oral cavity by the hard and soft palate.

The external nose is the anterior part of the nasal cavity, and paired openings at the back connect it to the pharyngeal cavity.

The nasal cavity is divided into two halves, each of which has five walls: inferior, superior, medial, lateral and posterior. The halves of the cavity are not entirely symmetrical, since the partition between them, as a rule, is slightly tilted to the side.

The most complex structure is at the lateral wall. Three nasal conchae hang inward on it. These shells serve to separate the upper, middle and lower nasal passages from each other.

In addition to bone tissue, the structure of the nasal cavity includes cartilaginous and membranous parts, which are characterized by mobility.

The vestibule of the nasal cavity is lined from the inside with flat epithelium, which is a continuation of the skin. The connective tissue layer under the epithelium contains the roots of bristle-like hair and sebaceous glands.

The blood supply to the nasal cavity is provided by the anterior and posterior ethmoidal and sphenopalatine arteries, and the outflow is provided by the sphenopalatine vein.

The outflow of lymph from the nasal cavity occurs in the chin and submandibular lymph nodes.

The structure of the nasal cavity is divided into:

  • The superior nasal passage, located only in the posterior part of the nasal cavity. As a rule, it is half the length of the average stroke. The posterior cells of the ethmoid bone are open into it;
  • The middle meatus is located between the middle and inferior conchae. Through a funnel-shaped canal, the middle meatus communicates with the anterior cells of the ethmoid bone and the frontal sinus. This anatomical connection explains the transition of the inflammatory process to the frontal sinus during a runny nose (frontal sinusitis);
  • The inferior meatus passes between the floor of the nasal cavity and the inferior concha. It communicates with the orbit through the nasolacrimal duct, which ensures the flow of tear fluid into the nasal cavity. Due to this structure, nasal discharge increases when crying and, conversely, quite often the eyes “water” when you have a runny nose.

Features of the structure of the mucous membrane of the nasal cavity

The mucous membrane of the nasal cavity can be divided into two areas:

  • The superior turbinates, as well as the upper part of the middle turbinates and nasal septum, are occupied by the olfactory region. This area is lined by pseudostratified epithelium containing neurosensory bipolar cells responsible for the perception of odors;
  • The rest of the mucous membrane of the nasal cavity is occupied by the respiratory region. It is also lined by pseudostratified epithelium, but it contains goblet cells. These cells secrete mucus, which is necessary to humidify the air.

Regardless of the area, the plate of the mucous membrane of the nasal cavity is relatively thin and contains glands (serous and mucous) and a large number of elastic fibers.

The submucosa of the nasal cavity is quite thin and contains:

  • Lymphoid tissue;
  • Nervous and vascular plexuses;
  • Glands;
  • Mast cells.

The muscular plate of the nasal mucosa is poorly developed.

Functions of the nasal cavity

The main functions of the nasal cavity include:

  • Respiratory. The air inhaled through the nasal cavity makes an arc-shaped path, during which it is cleaned, warmed and moistened. Numerous blood vessels and thin-walled veins located in the nasal cavity contribute to the warming of inhaled air. In addition, the air inhaled through the nose puts pressure on the mucous membrane of the nasal cavity, which leads to excitation of the respiratory reflex and a greater expansion of the chest than when inhaling through the mouth. Violation of nasal breathing, as a rule, affects the physical condition of the whole organism;
  • Olfactory. The perception of odors occurs thanks to the olfactory epithelium located in the epithelial tissue of the nasal cavity;
  • Protective. Sneezing, which occurs as irritation of the ending of the trigeminal nerve by coarse suspended particles contained in the air, provides protection against such particles. Tearing helps to cleanse the inhalation of harmful air impurities. In this case, the tear flows not only outward, but also into the nasal cavity through the nasolacrimal canal;
  • Resonator. The nasal cavity with the oral cavity, pharynx and paranasal sinuses serve as a resonator for the voice.

Found an error in the text? Select it and press Ctrl + Enter.

74-year-old Australian resident James Harrison has donated blood about 1,000 times. He has a rare blood type whose antibodies help newborns with severe anemia survive. Thus, the Australian saved about two million children.

Over the course of a lifetime, the average person produces no less than two large pools of saliva.

There are very interesting medical syndromes, for example, compulsive swallowing of objects. One patient suffering from this mania had 2,500 foreign objects in her stomach.

Scientists from Oxford University conducted a series of studies in which they came to the conclusion that vegetarianism can be harmful to the human brain, as it leads to a decrease in its mass. Therefore, scientists recommend not completely excluding fish and meat from your diet.

The cough medicine “Terpinkod” is one of the top sellers, not at all because of its medicinal properties.

A job that a person doesn’t like is much more harmful to his psyche than no job at all.

Human bones are four times stronger than concrete.

You are more likely to break your neck if you fall off a donkey than if you fall off a horse. Just don't try to refute this statement.

The liver is the heaviest organ in our body. Its average weight is 1.5 kg.

It was previously believed that yawning enriches the body with oxygen. However, this opinion has been refuted. Scientists have proven that yawning cools the brain and improves its performance.

Besides people, only one living creature on planet Earth suffers from prostatitis - dogs. These are truly our most faithful friends.

The average life expectancy of left-handers is shorter than that of right-handers.

American scientists conducted experiments on mice and came to the conclusion that watermelon juice prevents the development of vascular atherosclerosis. One group of mice drank plain water, and the second group drank watermelon juice. As a result, the vessels of the second group were free of cholesterol plaques.

Tooth decay is the most common infectious disease in the world, which even the flu cannot compete with.

If your liver stopped working, death would occur within 24 hours.

Omissions, disagreements, maiden name... Women's jealousy is a mystery for psychologists. Today, scientists do not fully know all the mechanisms that give rise to this strong and ra.

Source: http://www.neboleem.net/nosovaja-polost.php

Nasal cavity. Its structure and functions

The nasal cavity is the beginning of the respiratory tract. It is through it that air enters the body through a special channel that connects the external environment and the nasopharynx. In addition to the main respiratory function, it performs a number of other tasks: protection, cleansing and moisturizing. The size of the cavity increases with age; in older people it is approximately three times larger than in infants.

Structure

The nasal cavity is a rather complex formation. It consists of several parts, which include the outer part of the nose and the nasal passage, a number of skull bones that form it, cartilage, covered on the outside with skin, and on the inside with mucous membrane. This is just a general list of what the nasal cavity consists of.

Its structure is quite complex. So, the outer part of the nose is the wings (or the more popular name is the nostrils) and the back. The last component includes the middle part and the root, which goes into the frontal part of the face. From the side of the oral cavity, the nose is limited by the hard and soft palate. And from the inside, the cavity is formed by the bones of the skull.

The nose itself consists of two nostrils, between which a cartilaginous septum is installed. Each of them has posterior, inferior, lateral, superior and medial walls. Also, the anatomy of the nose includes a special zone that consists of blood vessels. By the way, this is one of the reasons for frequent bleeding in this area. The septum divides the nose into 2 parts, but not everyone has the same parts. It can be bent as a result of damage, trauma, or due to the appearance of formations.

The nasal passages are conventionally divided into the vestibule and the cavity itself. The first part is lined with squamous epithelium and covered with small hairs. And directly in the nasal cavity there is ciliated epithelium.

External stroke

Do not forget that air purification takes place in the nostrils. At the entrance there are tufts of hair, which are designed to retain large dust particles coming from the air. And the inner surface of the passage is lined with mucous glands, which protect the body from incoming microbes, reducing their ability to reproduce.

The nose has a root that is located between the eye sockets. Its back is facing down. The lower part of the nose, where the air intakes - the nostrils - are located, is called the apex. By the way, the holes through which breathing occurs are of different sizes for all people. This is due to the fact that the septum unevenly divides the nose; it does not run strictly in the middle, but is tilted to one side.

The wings of the nose are located on the lateral sides. Its outer part is formed by two bones and cartilage. The latter are located in the nasal septum and, with their lower edge, are connected to the soft tissues located there. The wings of the nose also contain up to 4 elastic cartilaginous plates, between them there is connective tissue, and they are covered with facial muscles.

Accessory cavities

The structure also includes the paranasal sinuses: sphenoid, frontal, maxillary, cells of the ethmoid labyrinth. They are divided into front and rear. This classification is necessary primarily for doctors, because their pathologies differ.

The paired maxillary sinuses of the nasal cavity are also called maxillary sinuses. They are shaped like a pyramid. They received their second name due to their location. One wall borders the nasal cavity. There is a hole on it that connects the sinus with the middle nasal passage; it is its overlap that leads to the development of inflammation, which is called sinusitis. From above, the cavity is limited by the lower wall of the orbit, and its bottom reaches the roots of the teeth. For some, they may even pass into this sinus. Therefore, sometimes even ordinary caries becomes the cause of odontogenic sinusitis.

The size of the maxillary cavities may vary, but each of them has additional depressions. They are called bays. Experts distinguish between zygomatic, palatal, frontal, and alveolar recesses.

The human nasal cavity includes paired frontal sinuses. Their posterior walls border the brain, its frontal lobe. In their lower part there is an opening that connects them with the frontonasal canal leading to the middle meatus. When inflammation develops in this area, a diagnosis of frontal sinusitis is made.

The sinus of the same name is located in the sphenoid bone. Its upper wall abuts the pituitary gland, the side wall abuts the cranial cavity and the carotid artery, the lower wall goes to the nose and nasopharynx. Because of this proximity, inflammation in this area is considered dangerous, but, fortunately, it is quite rare.

Otolaryngologists also distinguish the ethmoid sinuses. They are located in the nasal cavity and are divided into posterior, middle and anterior, depending on their location. The anterior and middle ones connect to the middle nasal passage, and the rear ones to the upper one. In essence, this is a combination of cells of the ethmoid bone of different sizes. They are connected not only to the nasal cavity, but also to each other. Each person can have from 5 to 15 of these sinuses, which are arranged in 3 or 4 rows.

Formation of structure

As a person grows, starting from birth, the nasal cavity changes. For example, children have only two sinuses: the ethmoid labyrinth and the maxillary sinus. In this case, only their rudiments can be found in newborns. They develop through the process of growth. Babies have no frontal cavities. But in about 5% of people they do not appear over time.

Also in children, the nasal passages are significantly narrowed. This often causes difficulty breathing in babies. The dorsum and root of the nose in newborns are not particularly pronounced. Their final formation is completed only by the age of 15.

Don’t forget that with age, nerve endings—the neurons responsible for the sense of smell—begin to die. This is why older people often cannot hear many odors.

Providing breathing

In order for air not only to enter the body, but also to be purified and moistened, it is provided that the nasal cavity has a specific shape. Its structure and functions ensure special passage of air.

The cavity consists of three shells, which are separated by passages. It is through them that air currents pass. It is worth noting that only the lower shell is true, because unlike the middle and upper shell, it is formed by bone tissue.

The inferior passage is connected to the orbit through the nasolacrimal duct. The middle one communicates with the maxillary and frontal sinuses; it forms the middle and anterior cells of the ethmoidal labyrinth. The posterior end of the superior turbinate forms the sinus of the sphenoid bone. The upper passage is the posterior cells of the ethmoid bone.

The sinuses are the accessory cavities of the nose. They are extruded by a membrane containing a small number of mucous glands. All septa, conchae, sinuses, and accessory cavities significantly increase the surface of the walls belonging to the upper respiratory tract. Thanks to all the plexuses, the nasal cavity is formed. Its structure is not limited to internal labyrinths. It also includes an outer part designed for air intake, purification, and heating.

The principle of operation of the upper respiratory tract

When entering the external nasal passage, air enters a well-heated cavity. The high temperature in it is achieved due to the large number of blood vessels. The air warms up quickly enough and reaches body temperature. At the same time, it is cleaned of dust and germs there thanks to a natural barrier of hair tufts and mucus. The olfactory nerve also branches in the upper part of the nasal cavity. It controls the chemical composition of the air and regulates the inhalation force depending on it.

When the nasal cavity, the structure and functions of which are designed to provide breathing, ends, the nasopharynx begins. It is located behind the nasal and oral cavity. Its lower part is divided into 2 tubes. One of them is respiratory, and the second is the esophagus. They cross at the throat. This is necessary so that a person can inhale air in an alternative way - through the mouth. This method is not very convenient, but it is necessary in cases where the nasal passages are closed. After all, it is for this purpose that the oral and nasal cavities are connected; they are separated only by the palatine septum.

But it is worth noting that when breathing through the mouth, the air is not able to sufficiently purify and warm up. That is why healthy people should always try to inhale air exclusively through their nose.

Mucous membrane

Starting from the outer part of the nose, the inner surface of the cavity is lined with special cells. There are about 150 mucous glands on every cm2. They produce substances that have a protective function. The nasal mucosa is designed to protect the body from the harmful effects of microbes that enter it through the air. Their main effect is aimed at reducing the ability of pathological organisms to reproduce. But besides this, a large number of leukocytes are released into the cavity through the cellular slits of the blood vessels. They are the ones who counteract the incoming microbial flora.

A huge part of the nasal cavity and the paranasal sinuses included in it are covered with small thread-like cilia. Several dozen such formations come off from each cell. They constantly fluctuate, making wave-like movements. They quickly bend towards the holes intended for exit and slowly return in the opposite direction. If you greatly enlarge them, you get a picture that resembles a field of wheat, which is agitated by the force of the wind.

The air in the nasal cavity must be purified. And the ciliary epithelium serves precisely to ensure that retained microparticles can quickly be removed from the nasal cavity.

Functions of the cavity

In addition to providing breathing, the nose is designed to perform a number of other tasks. Scientists have found that proper breathing ensures the correct functioning of the entire body. So, the main functions of the nasal cavity:

1) Breathing: it is thanks to the supply of air from the external environment that the saturation of all tissues with oxygen is ensured;

2) protection: as it passes through the nose, the air is cleaned, warmed, and disinfected;

3) sense of smell: recognition of odors is necessary not only in a number of professions (for example, in the food, perfume or chemical industries), but also for normal life.

A protective function can also include a reflexive call for necessary actions: this could be sneezing or even temporarily stopping breathing. The necessary signal is sent to the brain by nerve endings when they are exposed to irritating substances.

Also, it is the nasal cavity that performs the resonator function - it gives the voice sonority, tonality and individual color. Therefore, when you have a runny nose, it changes and becomes nasal. By the way, it is full nasal breathing that stimulates normal blood circulation. It promotes normal outflow of venous blood from the skull and improves lymph circulation.

Do not forget that the nose and nasal cavity have a special structure. It is thanks to the large number of air sinuses that the mass of the skull is significantly lightened.

Providing a protective function

Many people tend to underestimate the importance of nasal breathing. But without the normal performance of this function, the body is more susceptible to infections. The entire inner surface of the nose should be slightly moistened. This is achieved due to the fact that the goblet cells and corresponding glands produce mucus. All particles entering the nose stick to it and are removed using the ciliary epithelium. The cleansing process directly depends on the condition of this layer, which provides the basic functions of the nasal cavity. If the cilia are damaged, and this can happen as a result of an illness or injury, the movement of mucus will be impaired.

Lymphatic follicles, which are located in the vestibule of the nasal cavity and perform an immunomodulatory function, also serve for protection. Plasma cells, lymphocytes, and sometimes granular leukocytes are also intended for this purpose. All of them are gateways for pathogenic bacteria that can enter the body with air.

Possible problems

In some cases, the nasal cavity cannot perform all its functions in full. When problems arise, breathing becomes difficult, the protective function weakens, the voice changes, and the sense of smell is temporarily lost.

The most common disease is rhinitis. It can be vasomotor - at the root of the problem, it treats the deterioration of the tone of the vessels that are located in the submucosa of the lower conchae. Allergic rhinitis is just an individual reaction of the body to potential irritants. These include dust, fluff, pollen and others. Hypertrophic rhinitis is characterized by an increase in the volume of connective tissue. It develops as a consequence of other types of chronic nasal diseases. A runny nose can also be a consequence of taking vasoconstrictor medications for too long. This phenomenon is called rhinitis medicamentosa.

The mucous membrane of the nasal cavity can be damaged due to injury or surgery. In these cases, synechiae may form. Also, in cases of advanced rhinosinusitis, excessive growth of the mucosa is observed. In many situations, this is accompanied by an allergic runny nose. Another problem that the patient may encounter is the appearance of tumors. There may be cysts, osteomas, fibromas or papillomas in the nose.

Also, do not forget that often it is not the nasal cavity itself that suffers, but the paranasal sinuses. Depending on the location of inflammation, the following diseases are distinguished.

  1. When the maxillary sinuses are affected, sinusitis develops.
  2. Inflammatory processes in areas of the ethmoid labyrinth are called ethmoiditis.
  3. Frontitis is the name given to pathological problems with the frontal cavities.
  4. In cases where we are talking about inflammation of the main sinus, we talk about sphenoiditis.

But it happens that problems begin in all cavities at the same time. Then the otolaryngologist can make a diagnosis of pansinusitis.

ENT doctors can diagnose the acute or chronic nature of the disease. They are distinguished by the severity of symptoms and the frequency of manifestations of the disease. Frequently, common colds that are not treated in time lead to problems with the paranasal sinuses.

Most often, specialists encounter sinusitis or frontal sinusitis. This is due to the structure and location of the frontal and maxillary sinuses. This is why they are most often affected. If you feel pain in the area of ​​these cavities, it is better to go to an otolaryngologist who can make a diagnosis and select adequate treatment.

Source: http://www.syl.ru/article/168751/new_nosovaya-polost-ee-stroenie-i-funktsii

What structure does the nasal cavity have and what function does it perform?

The nose is a perfect and rather complex human sensory organ. Conventionally, it is divided into three large parts: the external nose, the nasal cavity and the paranasal sinuses. The visible part of the organ is formed over 15 years of life and often becomes the cause of significant experiences for a person, not corresponding to his ideas of beauty. Striving for the ideal, it is worth taking into account that any operations in the nasal area can disrupt its structure and lead to many unpleasant consequences.

The nasal cavity is an anatomical formation from which the human respiratory system originates. A number of processes take place in it to ensure humidification, purification and heating of the inhaled air. In addition, it performs a number of other vital functions due to its complex anatomy.

Structure of the nasal cavity

The nasal cavity is divided by the septal plate into 2 approximately equal parts. These halves are connected to the external environment through the external nose, formed from bones and cartilage. The skeleton is covered by muscle tissue and skin.

The septum has a rather complex anatomy. In the area of ​​the wings of the nose, it begins with a movable membranous region, continues with a small cartilaginous plate - an irregular quadrangle, communicated through its angles with the bones: nasal, ethmoid and palatine.

The cartilage ends in a bone area formed at the site of fusion of the ridges of the upper jaws, vomer, ethmoid, frontal, and sphenoid bones.

The nasal cavity communicates with all the paranasal sinuses through canals.

The nasal cavity is limited by 3 walls:

  1. Upper. It is called the arch of the nose. Formed by the sphenoid, frontal, ethmoid bones and the inner surface of the nasal bones.
  2. Bottom. It is called the bony palate because it separates the nasal cavity from the oral cavity. It is formed as a result of the fusion of the process of the upper jaw with the horizontal plate of the palatine bone. Pathologies in this area often cause defective conditions: cleft palate or cleft lip.
  3. Lateral. It is formed by the nasal, maxillary, sphenoid, palatine, ethmoid and lacrimal bones.

There are 3 conchae on the lateral wall of the nasal cavity. They are plate-shaped and stacked on top of each other, as seen in the image below. The upper and medial conchae are represented by processes of the ethmoid bone, the lower one is an independent formation.

The nasal turbinates form 3 paired nasal passages:

  1. The upper one is the smallest passage, located in the back of the nasal cavity, in contact with the palatine opening.
  2. The middle stroke is the widest and longest. It is formed not only by bone tissue, but also by fontanelles of the mucous membrane. Through the falciform fissure, the medial passages communicate with the maxillary sinuses. On the rear walls they have funnel-shaped extensions, through which the passages communicate with the frontal sinuses.
  3. The lower passage is limited by the bottom of the cavity and the lower shell. In the area of ​​its fornix, the nasolacrimal duct opens with a hole, through which liquid secretions flow from the space of the eye orbits. This anatomical connection leads to the fact that during crying, mucus is intensely separated into the nasal cavity, and when there is a runny nose, tears are released from the eyes.

The area between the nasal concha and the septal plate is called the common nasal meatus.

Device of the nasal mucosa

Conventionally, the nasal cavity is divided into 3 areas:

  1. The vestibule is covered with flat epithelial cells (the area of ​​the skin contains glands and hair follicles), which pass into the mucous membrane. The latter contains anatomical devices for the cavity to perform its functions.
  2. The respiratory region is a section of the mucous membrane adapted to process the air entering the nasal cavity. It is located at the level of the middle and lower moves.
  3. The olfactory region is part of the mucous membrane responsible for the perception of odors. The department is located at the top level.

The mucous membrane is covered with ciliated epithelial cells - cells with many microscopic cilia on their free edge. These cilia continuously carry out wave-like movements towards the exit of their nasal cavity. With their help, small particles of air dust are removed from it.

The nasal mucosa covers all surfaces of the cavity except the vestibule and nasopharynx.

The membrane contains secretory cells and glands. Their active work helps to humidify the air entering the respiratory tract and clean it of contaminants (the secretion envelops foreign particles for their subsequent removal).

The shell is entangled in a dense network of capillaries and small vessels that form plexuses in the area of ​​the inferior and middle conchae of the nose. The air is heated through a well-developed vascular bed. Also, cells (leukocytes) enter the nasal cavity through thin capillary walls, ensuring the neutralization of bacterial and microbial components.

Functions of the nasal cavity

The structure and functions of the human nasal cavity are interconnected. Thanks to its anatomical features, it provides the following functions:

  1. Respiratory. Air enters and exits the respiratory tract through the cavity. At the same time, it is cleansed, moistened and heated. The physiology of human breathing is designed in such a way that the volume of air inhaled through the nose is several times greater than the volume inhaled through the mouth.
  2. Olfactory. Odor recognition begins with the peripheral processes of the olfactory nerve capturing the smallest odorous particles of a substance. The information then goes to the brain, where the smell is analyzed and perceived.
  3. Resonator. The nasal cavity, together with the vocal cords, sinuses and oral cavity, ensures the formation of the individual sound of the voice (participates in the formation of sound resonance). During a cold, the nose is blocked, which is why the human voice sounds different.
  4. Protective. Secretory epithelial cells secrete special bactericidal substances (mucin, lysozyme). These substances bind pathogenic particles, which are then (with the help of ciliated epithelium) removed from the cavity. A dense capillary network ensures the formation of the body’s immune gate (leukocytes capture and destroy bacteria, fungi, viruses). Sneezing is also protective in nature: it is a strong reflex exhalation due to irritation of the olfactory nerve by coarse particles.

Conclusion

The nasal cavity is a complex anatomical formation. In order to understand what function the nasal cavity performs, it is necessary to know the features of its structure (mucous membranes, cartilage and bone skeleton). Being the entrance for air on its way to the human lungs, it performs a respiratory, protective, olfactory function, and also participates in the formation of the voice.

Most people are concerned about the shape of the nose, and few people think about how it works. Since even minor problems with the organ of smell can instantly affect a person’s well-being, the necessary measures should be taken in a timely manner to eliminate them. All colds should be treated in a timely manner and do not forget about daily care.

Directory of main ENT diseases and their treatment

All information on the site is for informational purposes only and does not claim to be absolutely accurate from a medical point of view. Treatment must be carried out by a qualified doctor. By self-medicating you can harm yourself!

Source: http://gorlonos.com/nos/kakuyu-funktsiyu-vypolnyaet-nosovaya-polost.html

Structure and functions of the human nose

The nose is an important part of the human body. It has a rather complex structure and performs many functions, providing free breathing and sense of smell. From the point of view of clinical anatomy, the nose is usually divided into external and internal parts.

Structure of the external nose

The outside of the nose is covered with skin, which contains many sebaceous glands. This section of the nose consists of cartilage and bone tissue and is shaped like a triangular pyramid. Its upper part is usually called the root of the nose, which, lengthening, passes downwards into the back and ends at the apex. The wings of the nose are located on the sides of the back, they are movable structures and form the entrance to the nasal cavity.

The bony skeleton of the nose consists of thin and flat nasal bones; they are connected to each other (along the midline), as well as to other structures of the facial skeleton. Its cartilaginous part is represented by paired lateral cartilaginous plates located above and below.

This section of the nose is abundantly supplied with blood by the branches of the external carotid artery. The outflow of venous blood from this area has certain features, which is carried out into the anterior facial vein, which communicates with the ophthalmic vein and the cavernous sinus. This structure allows for the rapid spread of pathogens of infectious diseases through the bloodstream into the cranial cavity.

Inner part of the nose

The nasal cavity is located between the oral cavity, the orbits and the anterior cranial fossa. It communicates with the environment (through the nostrils) and the pharynx (through the choanae).

The lower wall of the nasal cavity is formed by the palatine bones and the processes of the same name of the upper jaw. In the depths of this wall, closer to the anterior, there is an incisive canal in which nerves and vessels pass.

The roof of the inner nose is formed by the following bone structures:

  • cribriform plate of the same bone;
  • nasal bones;
  • anterior wall of the sphenoid sinus.

Olfactory nerve fibers and arteries penetrate here through the cribriform plate.

The nasal septum divides the nasal cavity into two parts - cartilaginous and bone:

  • The latter is represented by the vomer, the perpendicular plate of the ethmoid bone and the nasal ridge of the upper jaw.
  • The cartilaginous part is formed by the own cartilage of the nasal septum, which has the shape of a quadrangle, which participates in the formation of the dorsum of the nose and is part of the movable part of the septum.

The lateral wall of the nasal cavity is the most complex. It is formed by several bones:

It has special horizontal plates - the upper, middle and lower nasal concha, which conditionally divide the internal part of the nose into 3 nasal passages.

  1. Inferior (located between the nasal concha and the bottom of the nasal cavity; the nasolacrimal canal opens here).
  2. Middle (limited by two nasal conchas - inferior and middle; has anastomosis with all paranasal sinuses, except the sphenoid).
  3. Superior (located between the vault of the nasal cavity and the superior nasal concha; the sphenoid sinus and the posterior cells of the ethmoid bone communicate with it).
In clinical practice, the common nasal passage is distinguished. It looks like a slit-like space between the septum and the nasal turbinates.

All parts of the inside of the nose, except the vestibule, are lined with mucous membrane. Depending on its structure and functional purpose, the respiratory and olfactory zones are distinguished in the nasal cavity. The latter is located above the lower edge of the middle turbinate. In this part of the nose, the mucous membrane contains a large number of olfactory cells that can distinguish more than 200 odors.

The respiratory region of the nose is located below the olfactory region. Here the mucous membrane has a different structure; it is covered with multinucleated ciliated epithelium with many cilia, which in the anterior sections of the nose make oscillatory movements towards the vestibule, and in the posterior sections, on the contrary, towards the nasopharynx. In addition, this zone contains goblet cells that produce mucus and tubulo-alveolar glands that produce serous secretions.

The medial surface of the lower part of the middle turbinate has a thickened mucous membrane due to cavernous tissue, which contains a large number of venous dilations. This is precisely what is associated with its ability to quickly swell or contract under the influence of certain stimuli.

The blood supply to the intranasal structures is carried out by vessels from the carotid artery system, both from its external and internal branches. That is why, in case of massive nosebleeds, it is not enough to bandage one of them to stop it.

A feature of the blood supply to the nasal septum is the presence in its anterior part of a weak spot with thinned mucous membrane and a dense vascular network. This is the so-called Kisselbach zone. There is an increased risk of bleeding in this area.

The venous network of the nasal cavity forms several plexuses in it, it is very dense and has numerous anastomoses. The outflow of blood goes in several directions. This determines the high risk of developing intracranial complications in diseases of the nose.

The nose is innervated by the olfactory and trigeminal nerves. The latter is associated with possible irradiation of pain from the nose along its branches (for example, into the lower jaw).

Functions of the human nose

The normal functioning of the nasal cavity is of great importance for the full functioning of distant organs and systems of the whole body. Thus, with free nasal breathing, 10 times fewer microorganisms penetrate into the respiratory tract than with mouth breathing. Difficulty breathing through the nose contributes to acute respiratory viral infections, sore throat, and bronchitis.

In addition, adequate functioning of the nose is necessary for normal blood gas exchange. Chronic nasal diseases with congestion or narrowing of the respiratory space lead to insufficient oxygen supply to the tissues and disruption of the nervous system.

Prolonged difficulty in nasal breathing in childhood contributes to delayed mental and physical development, as well as the development of deformation of the facial skeleton (alteration of the bite, high “Gothic” palate, curvature of the nasal septum).

Let us dwell in more detail on the main functions of the human nose.

  1. Respiratory (regulates the speed and volume of air entering the lungs; due to the presence of reflexogenic zones in the nasal cavity, it provides broad connections with various organs and systems).
  2. Protective (warms and moisturizes the inhaled air; the constant flickering of the cilia cleanses it, and the bactericidal effect of lysozyme helps prevent pathogens from entering the body).
  3. Olfactory (the ability to distinguish odors protects the body from the harmful influences of the environment).
  4. Resonator (together with other air cavities, it participates in the formation of the individual timbre of the voice and ensures clear pronunciation of some consonant sounds).
  5. Participation in lacrimal drainage.

Conclusion

Changes in the structure of the nose (developmental anomalies, curvature of the nasal septum, etc.) inevitably lead to disruption of its normal functioning and the development of various pathological conditions.

Source: http://otolaryngologist.ru/3459