The structure of the hair

In the scalp and body there are countless tiny hair follicles – follicles from which the hair grows. Follicles end in thickening of the hair bulb, which is the papilla, consisting of a dense plexus of nerve fibers and blood vessels that supply the hair with all the necessary. In hair efficacy constantly produce new cells that move up on it and go out through a hole in the skin pore. This part of the hair, which is under the skin, the root is alive, and the hair growing over the skin is dead. Man is born already with all the hair follicles, which will appear on his head. From changes of density of follicles depends on hair growth and type. Almost no follicles are not destroyed if the process of hair growth will proceed normally.

Primary hair appears in the fetus in the womb. It disappears gradually after birth, going into the fluff, which is then replaced by long and coarse hair. Part of the hair in the chest, under the arms, in the pubic area – appears later, during the maturation of the body.

The curliness of hair depends on the shape of the bulb. Round follicles grow straight hair, oval is wavy or curly, from follicles in the form of kidney or beans obtained curly, hard.

In the context of hair has three layers – outer cuticle, middle soft – medulla, and cortical. The cuticle is the scaly layer, thin, flat, keratinized cells that consists of protein – keratin.

Medulla – soft substance is not fully keratinized flattened round cells that are cleaved, which makes the hair thin and brittle.

Cortical layer consisting of dead cells that provides the hair with elasticity. Its weight reaches 90 % of the total weight of the hair. In the cortical layer is a dye – pigment called melanin. It is black, yellow, red. The colour of the individual depends on how the combination of these colors in the structure of the hair. Melanin is not soluble in water but quite soluble in alkalis, acids, oxidants, and that gives the ability to change the color of hair by artificial means.

Keratin is a protein compound, the protective layer of the hair, retaining the Shine and giving the hair grease secreted by the sebaceous glands that are attached to the hair SAC. The combination of keratin and melanin determine the different quality of hair of a particular person, color, elasticity, durability, ability to retain moisture, the ability to staining, and more.

It is on keratin and influence of many modern cosmetics for hair, developed by experts in order to preserve the natural structure of the hair, improve it, and in cases of its violation.

From the chemical point of view, hair is a complex compound consisting of oxygen, carbon, nitrogen, hydrogen and sulfur. In percentages, the hair contains carbon, almost 50 %. Than thicker hair, so they are less. The thickest hair – red, the most delicate light. The brunettes hair thickness is average. The blond on the head about 140 000 hairs. Beard hair in 5-6 times less, than on the head. Hair eyelashes – 150-200 on the upper eyelid, the lower they are less likely to: 75-100 hair.

The lifespan of a hair is approximately four years. The speed of hair growth per day on average is 1/2 mm. the Maximum length of the hair, if not to take into account exceptional cases – 80 cm In old age, hair growth slows down.

As to speed hair growth on other parts of the body, it is very fast to grow hair on beard and very slowly in the eyebrows.

For a number of reasons, which we will discuss below, the hair falls out. After each combing the comb is a small amount of hair (30-40), which is considered quite normal.

On the head hair loss occurs every 2-4 years, and eyebrows, eyelashes and hair of the armpits fall out every 3-4 months.

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