Skin analyzer: structure, function and value. Anatomy of the skin

With such a notion as a "skin analyzer", not all people came across. Most people used to call it a shorter, more familiar term. That is skin. But, in fact, both of these concepts mean a complex organ, which is our outer covering. One of the few in our body, to which you can easily touch at any time. The area of the skin of an adult is about 1.5 - 2.3 square meters. And the mass, together with the hypodermis (the cover layer, which is deeper than the surface layer), is 16-17% of the body weight. However, all this should be told in more detail.

Epidermis

First of all, when talking about the skin analyzer, it is necessary to touch the epidermis. It is our outer layer. But this is simple language. In fact, the epidermis is a multilayered derivative of the epithelium. In thick skin, which is not covered with hair, it includes as many as 5 layers. Each of them is located above the dermis. And they all carry out the barrier function.

Important nuance: the epidermis is characterized by a constant renewal. And this specificity is related to the migration and transformation of the so-called keratinocytes. These are cells of epithelial tissue. Their filaments are represented by protein keratin. In addition, it is also important to know that the epidermis contains certain components of the immune system.

Structure of the epidermis

Anatomy of the skin is very complicated. Only the epidermis (one of its components) includes five different layers. The first is basal. Or, as it is also called, sprout. What is really important to know about the basal layer is that it contains so-called melanosomes. These are pellets of melanin, which protect us from the effects of UV rays.

The second layer is called spiny. It also includes a mass of cells, but the most important "brick" can be considered a tonofibrillar apparatus. It is the protection of the nucleus of cells from mechanical damage.

There is also a grainy layer. Composed of 1-2 rows of elongated cells. It is in this layer that filagrin and keratolinin (structural proteins) are synthesized. And they contribute to the keratinization of the epithelium. This, by the way, is the most complicated process, thanks to which the horny dermal words acquires its inherent elasticity and strength.

The fourth layer is known as cyclic (or shiny). There are no organelles or nuclei in its cells. And it looks like a brilliant pinkish strip. This layer is perfectly developed on the soles and palms.

And the last one is horny. This is the skin that performs a protective function. There are no living cells in it. What is not surprising, because it is formed by dead keratinocytes. Or, as they are called, horny scales. The extent to which this layer is thick, depends on the loads exerted on this skin.

Dermis

This is the next thing that should be noted with attention, telling about the skin analyzer. Because the dermis is actually the skin. And if expressed in scientific language - connective tissue part of it.

The dermis is under the epidermis. But not directly, they are shared by the basal membrane. It is distinguished by the abundance of capillaries and fibers, due to which the dermis is assigned the supporting and trophic functions. It, like the epidermis, consists of several layers. True, of the smaller number of them there are only three.

The components of the dermis

Anatomy of the skin is very complicated, but you can understand it. There are only three layers, and the first that deserves attention is papillary. Why is it called that? Because this is the first layer, is represented by "papillae", which penetrate the epidermis. It consists of dozens of "components". These are tissue basophils, macrophages and many other cells that promote the protective function of our immune system.

The second layer is called the mesh layer. It forms a dense fibrous connective tissue. Strictly speaking, this is the main part of the dermis. It is in the mesh layer that the most powerful collagen fibers that support the performance of the supporting function are contained.

The last layer is called the hypodermis. It is also called subcutaneous fatty tissue. It is located directly under the dermis. And, as you can understand, based on the name, is formed by fat tissue. It is due to it that water and nutrients accumulate under the skin. In addition, the hypodermis promotes thermoregulation.

Functions: protection and purification

So, what is a skin analyzer, it is clear. Now you can list the functions it performs.

The first is protective. As already mentioned, the epidermis protects the nerves, tissues and blood vessels from the direct influence of the external environment. The skin contains sebaceous glands. They are of the order of 300,000. And for a month they produce an average of 500-800 grams of fat. It lubricates the surface of the skin, thus protecting it from various effects.

The second function is purifying. The skin is characterized by sweat. So it releases the body from substances that are unfavorable to the body, trapped inside with medicines or food. Interestingly, there are about 2 million sweat glands in the skin .

Regulation, nutrition and respiration

These are also functions of the skin analyzer, which are traditionally referred to as the main ones.

So, the regulation. The skin cools the blood if the external temperature is below that characteristic of the body. The opposite effect it has in the opposite case. If the temperature of the environment is very high, the skin muscles become relaxed, so that the vessels expand, and the heat output of the body increases. The influx of blood is also accelerating. As a result - a profuse allocation of sweat.

The fulfillment of the function of nutrition is also conditioned by the departments of the skin analyzer. It is through our cover that animals, as well as vegetable fats, penetrate the interior of the body. Solutions and creams are absorbed due to their special structure. It is not for nothing that these cosmetic substances are often called "nutritious".

The respiratory function, in principle, is characterized by the same specificity. Due to the porous structure of the upper layer, 2% of carbon dioxide is released through the skin. Certainly not everyone knows that in 24 hours our cover removes about 800 grams of water vapor!

Nerve links

Above there was a lot said about what the human skin is. The structure and functions of it are of particular interest. And one can not help but mention the topic of nerves with which our "shell" is abundantly supplied.

If expressed in accessible language, then the skin is a large field, strewn with receptors. They constantly, every second, perceive irritations of a different nature, coming from the internal and external environment.

Nerve fibers and endings (both encapsulated and free) - that's what the human skin contains. Their structure and functions are specific. The nerve apparatus is located in the epidermis and dermis. In the hypoderm, there are practically none. It penetrates only the nerve trunks that form there plexus, from which the fibers go into the dermis. From there - to the hair sacs, muscles, vessels and sweat glands.

Nerve endings have their names. For example, thanks to Krause's flasks, the skin feels cold. And Meissner's bodies help to perceive the touch. Due to the bodies of Ruffini we feel the warmth. You can enumerate for a long time. But the most interesting is that one square centimeter of skin accounts for about 200 painful, 2 thermal, 12 cold and 20 tactile receptors.

Blood

Naturally, the structure of the skin analyzer has a specific specificity, due to which blood circulation is carried out.

So, in the hypoderm, in addition to nerve fibers and endings, there are large vessels. There are even arteries. They originate from the so-called arterial network, located directly above the fascia. About them it was said at the very beginning.

From there, the arterial network extends further into the deep parts of the reticular layer. And from there - straight to the papillary.

It is important to know that in the skin layers there are not only capillaries and venules, but also arterioles. Which directly participate in the regulation of OPSS (general peripheral vascular resistance). Arteriolar tone is extremely important. Because of it depends on the peripheral resistance, which determines the blood pressure. This is the characteristic of the skin analyzer. However, it does not surprise. After all, we are talking about a single, holistic organism in which absolutely everything is interconnected.

Sensitivity

This topic is also worth noting with attention. There is such a thing as skin-and-muscle sensitivity. Its origin is understandable. After all, it is not uncommon for the muscles to be affected by touching the skin beforehand. Take, for example, the same massage.

But skin sensitivity is special. It is composed of different analyzers. Touch, for example, is a complex feeling that arises from the feeling of objects. Tactile sensations play an important role here. Analyzers that perceive pressure and touch give us information about the density of the object, its shape, temperature, state, size and much more. Especially a lot of receptors are concentrated on the fingertips. It is from them that the "way" of information signals transmitted to the brain begins.

Regeneration

It can be of two kinds. The first is called physiological. It is quite normal, natural process, involving the renewal of cells. Its course depends on nutrition, physical health and human immunity. This, in turn, affects the look and youth of the skin.

A reparative regeneration implies the restoration of the cover after mechanical damage. After a surgical operation, for example. The process is very interesting. First, the inflammation phase proceeds - bleeding stops, there is swelling, pressing on the nerve endings and causing pain. Then proliferation begins. The wound is filled with capillaries and connective tissue - thereby collagen. The last phase implies scar formation. This process ends with the filling of the site with epithelial tissue.

Some scars can form a year. And let the skin is characterized by regeneration, without a trace of damage do not pass. Because you need to be treated with care.

Interesting Facts

It is worthwhile to finish the story about what is the skin-muscular sensitivity (the structure of the analyzer and its functions we also considered). Indeed, there are several interesting facts, and here are some of them that deserve attention:

• It is difficult to imagine, on the whole surface of our skin there are about five million hairs!
• In an adult, the skin is 60% moisture. Children - by 90% (but this is the maximum).
• For every square centimeter of skin there are 100 pores.
• On average, the cover reaches 1-2 millimeters in thickness.
• The roughest skin on the soles. The most thin and transparent - on the eyelids.
• Throughout life, about 18 kilograms of keratinized skin is replaced with a new one.

Well, a lot more can be told interesting about our cover, its structure and specific features. But the basic positions of anatomy were listed above, and it is useful to remember them for everyone, since this topic concerns all of us directly.