The skin is vital in our body that goes beyond the aesthetic-looking.Just think that the living skin daily contact with a whole series of external agents sometimes very harmful, where it exerts a continuous defensive action.The skin consists of three main states superimposed: epidermis, dermis, subcutaneous tissue.Each has a specific role
The epidermis presents outside a state horny is what we see, made up of keratin cells the same substance as fingernails are made.These cells do not always live but will continuously regenerate.In fact, they die all the time and are replaced by others, in a life was calculated that regenerate up to twenty pounds of skin.
The dermis is formed, in its upper part, by semi-conical papillae that protect the capillary system, responsible for the nutrition of the cells.And ‘the dermis that gives skin softness and elasticity.
The hypodermis consisting mainly of fat-rich cells has the function of shock absorber between the dermis and subcutaneous tissues.The fat that make up the hypodermis is a crucial issue in the wrinkle formation mechanism: when, in fact, the fat was thin in a region, the overlying skin is to lose part of its support and form an imperceptible furrow the dreaded wrinkles.
The skin, in all its thickness holds two types of glands: the sebaceous and sweat ones.The first, sebaceous, result in the highest part of the sheaths from which originate the hairs.Their function is to lubricate the skin, with oily substance they manufacture the “sebum.”They are particularly numerous on the sides of the nose and on the eyelids, in the hairy region and the breasts.
Even the sweat glands are distributed all over our skin, but are most numerous in certain specific areas such as the palms of the hands, soles of the feet, armpits, groins, forehead, scalp This leads glands outside by the pores.
SKIN AND THE EIGHT FUNCTIONS
The skin is at the same time:
A device respiratory
An air conditioner,
A protective enclosure
A factory of vitamin.
Amphora because no living being could survive in the atmosphere if it were completely protected by a waterproof layer which allows him to entertain as much water as the body needs.The state stratum of our skin performs this function because it is made from keratin cells, impermeable substance.This impermeability is accentuated by the sebum produced by the sebaceous glands, which is located on the epidermis, and that constitutes a true protective film.This explains why fatty substances, such as creams, liquids more easily penetrate below the epidermis.The fat creams that have a composition similar to sebum, infiltrate in small amounts in the skin.
Respiratory protection because the skin is waterproof but not air.In fact, we breathe through the skin pores, and even if the amount of air so absorbed is very small, it is essential for life.In fact, a man or a woman covered with paint die of suffocation after a very short time because they can not, has to breathe through the skin pores.
A purifier since the skin has an auxiliary function to that of the kidneys, eliminating toxins through sweat and gut fermentation products through the sebum.The sweat glands, are activated not only by thermal effect but also and especially by psychic stress and nerve managing to eliminate in a manner unnoticeable, but continues from 500 to 700 grams of sweat in the space of a day.This phenomenon is called transpiration.
An air conditioner because the continual changes in temperature and humidity, the skin is opposed changing the size of the vessels and the activity of the sebaceous and sweat glands.The cold causes a narrowing of the vessels and consequently, the skin receives less blood flow which, having thus decreased its long path, circulates more quickly, while the temperature remains constant at about 37 degrees.On the contrary the increase of temperature causes a vasodilatation with consequent slowing of movement and greater heat dispersion.It also produces a large amount of sweat and with it removes water, which evaporates and lowers skin temperature.Even under normal temperature conditions the skin eliminates water ensuring the normal maintenance of body temperature and contributing decisively to the right water balance.
A warehouse our organism absorbs water, fats, salts, and other vital elements, such as iron, manganese, phosphorus and potassium, in excess amount to its normal requirements, the skin accumulates this surplus.If these substances are, to be insufficient at the right organic balance, blood recovers in the skin and carries them to the organs that need them.
A radar one of the most important functions of the skin is sensitive, through which it becomes aware of the outside world, recording the shape and texture of objects, reacting to cold, heat, pain.The skin should this property to the numerous nerve endings in it.They receive external stimuli and transmit them to the spinal cord and the brain, which records them and processes them, and when necessary, sends an impulse-response in the muscles and glands.These nerve endings are not equally distributed across our skin, but they are abundant on hands and lips, where the sensitivity is more alive.The transmission of stimuli may also take place without a direct contact with the skin, but through the mediation of the hairs and hair.
A protective covering our skin also protects our body from trauma, injury and, in part, from the attack of microbes.The fat content in the hypodermis cushion the blows, as well as a packaging batting defend a fragile and precious object.Against wounds the skin uses another weapon, and that is the faculty that the lower layer of the epidermis has to multiply the cells and, therefore, to heal the wounds.In the same way, when the skin is subjected to a repeated and prolonged pressure, the bottom layer of cells accelerate the pace of their play to “send” in the affected area, with reinforcement cells battalions.The state corneum thickens, it becomes harder, thereby protecting the deep states.And ‘This is the process of formation of calluses.The most common are on the hands of those who do heavy work and on the soles of our feet.Finally the defense by microbes is due to an acid protective film which extends over the entire horny layer of our skin.This film is made up of fats, products of the secretion of sweat and sebaceous glands, mixed with elements of scaling and state horny parts that collect on the skin surface.This film is formed and is continually renewed, so removing the specks of dust and killing, due to the acidity, the bacteria.
A factory of the skin vitamins is capable of processing certain vitamins such as, for example, vitamin D, which from proto-vitamin is transformed into active vitamin under the chemical action of the sun’s rays.The cutaneous capillary vessels then carry the body, where it is essential to the assimilation of calcium, so useful against forms of rickets.