The nose is the initial section of the human respiratory tract (respiratory tract), which has a number of important functions, such as warming and partially moistening the air, cleansing it of pathogenic microorganisms and dust particles, as well as its further passage to the throat. In addition, the sinuses are good sound resonators and are involved in the formation of human speech. The anatomy of the nose is extremely complex and interesting. Consider the structure of the nose in more detail.
Nose structure: departments
It is customary to distinguish two sections of the nose: the nasal cavity (inner part) and the outer nose.
The shape of the outer nose resembles a pyramid, consists of cartilage and bone. The bones of the external nose attach to the frontal bone, forming the back of the nose. The wings are formed by lateral cartilage, which, like the cartilage of the nasal septum, are of great importance in the formation of the shape of the nose. Cartilage along with the nasal bones form a special anatomical structure called the nasal slope. As an anatomical formation, the external nose is present only in humans, its appearance is associated with a change in the method of movement (vertical walking on two limbs) and the development of speech.
The nasal cavity is much more complex than the outer nose, located inside the skull, bordered by important anatomical formations - the oral cavity, the anterior cranial fossa and the orbits. The nasal cavity communicates through the choana with the pharynx, as well as through the pear-shaped opening, which is formed by the nasal and facial bones, with the vestibule of the nose.
The facial bones and cranial bones form several walls in the nasal tissue. The upper and outer walls are formed by the ethmoid bone, the inner wall by the bony nasal septum, and the lower by the palatine processes of the upper jaws. The most complex structure is the outer wall, which has three bony protrusions, also called nasal concha: lower, upper and middle. The lower shell, which is a separate, independent bone, has the largest dimensions. The middle and upper shells are processes of the ethmoid bone. Each shell is located above the nasal passage, which is also three: upper, lower and middle. All three nasal concha and nasal septum are separated by a free space called the common nasal passage. This structure of the nose, namely, this system of nasal cavities is of great importance in moisturizing and warming the air entering through the nose.
In addition to bone and cartilage, which play a major role in the formation of the nose and maintaining its shape, a large number of functions are performed by the mucous membrane of the nasal cavity. It is divided into two departments: olfactory and respiratory. The olfactory area is strictly specialized and contains a huge number of olfactory receptors designed to perceive odors. The receptors of the olfactory region may completely or partially lose their function. This happens when working in dusty and smoky conditions, with frequent colds and viral diseases, and constant exposure to harmful toxic substances.
Most of the nose is lined with the respiratory component of the mucous membrane, which has many structural features. These features are primarily aimed at the processing of air conducted through the nasal cavity. The entire surface of the respiratory mucosa is covered with a huge number of cilia, on which dust particles are retained, and thanks to the continuous oscillation of the cilia towards the exit, they are all removed quite quickly. In addition, the entire surface of the mucous membrane contains specific mucous glands, which secrete a special mucus that collects dust and germs on its surface and then evacuates them. The composition of this mucus includes many substances that fight bacteria and pathogenic microbes. In the nasal wall, directly under the mucous membrane, there are many veins forming the plexus, the main purpose of which is to heat the air entering the nose.
As mentioned above, the structure of the nose is much more complex than it might seem at first glance. Our nose has special "secret rooms" - sinuses that open into the nasal cavity and perform additional heating of the air. The sinuses of the nose are covered with mucosa, there are 4 types in total:
1. The maxillary or maxillary sinuses. They are located on the right and left in the thickness of the upper jaw. The entrances of these sinuses are almost completely closed by the mucous membrane.
2. Frontal sinuses, also paired, they are located in the frontal bone.
3. In the body of the ethmoid bone, represented by many cells, there is the ethmoid sinus.
4. A single sphenoid sinus is located under the Turkish saddle in the body of the sphenoid bone.