Structure A large number of problems in the intimate sphere, as well as the inability to tell your children “about it”, arise precisely from ignorance of basic things, one of which is the structure of one’s own body. Let's start with this. The female reproductive system has in common

Hair is the natural adornment of any woman. Curly and straight, voluminous and smooth, long and short, light brown and chestnut - what does all this diversity depend on? First of all, it depends on the structure and composition of the hair that is given to us from birth.

Hair structure

The structure of hair is not as simple as it might seem. Each hair consists of a visible part - the shaft - and an invisible part, immersed in the skin - the root. At the bottom of the root is the source of life of the hair - a small papilla permeated with nerves and blood vessels.

Through this papilla, the hair is nourished and maintained. From here the hair begins to grow. The entire hair root is enclosed in a hair follicle.

The number of follicles is genetically determined in us, so the number of follicles we have at birth is the amount of hair we will have on our heads throughout our lives. The number of hairs ranges from 80 thousand for redheads to 150 thousand for blondes. Moreover, there are more of them on the crown than at the forehead and temples.

The deepest expanded part of the root is called the bulb. The place where the hair exits the skin surface coincides with the place where the surrounding sebaceous glands exit. It's called the hair pore. The sebum released from the sebaceous gland lubricates the outer part of the hair and maintains its elasticity. If little oil is produced, the hair becomes dull and brittle.

A small hair muscle, regulated by the nervous system, approaches the hair root from the surface of the skin. When this muscle contracts, the hair takes on a vertical position and “stands on end.” This is especially noticeable when a person is afraid.

The hair shaft, which gives each of us a unique look, consists of three layers:

• The outer layer is the cuticle. It consists of 7-9 rows of horny plates arranged in the form of tiles. In the “open” state of the hair, the scales are arranged loosely and move away from the surface. In the “closed” state, the scales are pressed to the surface, the hair becomes denser and acquires shine. Under the influence of alkali (soap), the hair swells and opens its scales, and under the influence of acid (rinse aid), it “closes.”
• The middle layer is the cortex. It gives hair flexibility, elasticity, and contains the pigment melanin, which determines its color. Melanin does not dissolve in water, but interacts with alkalis and acids. In older people, the pigment disappears and the hair turns gray.
• The last layer is the medulla. The deepest layer, the pulpy, medullary, consists of incompletely keratinized cells. It may be absent in extremely thin hair.

The texture of the hair is determined by the diameter of the shaft, depending on which the hair is divided into thick, medium and fine.

Hair porosity- This is their ability to absorb moisture. Hair with low porosity does not absorb moisture well, which creates some difficulties when coloring and curling such hair. Excessive porosity makes hair dull, depriving it of shine and vitality. This type of hair requires treatment.

Elasticity is the ability of hair to withstand bending, compression and tension without breaking. Springy, vibrant, shiny hair with normal porosity has great elasticity and, when wetted, can increase its length by 20%.

The length of the hair also affects its quality. The ends of long hair tend to be super porous. In general, the longer the hair, the lighter and coarser it is at the ends. The length of the hair itself depends on many factors. Some people have hair that grows below their shoulders, while others grow it to their waist. The most long hair- 7 m 90 cm - were from Swami Pandarasande, caretaker of the Indian monastery.

The structure and composition of hair allows us to divide them into three ethnic groups:

• Caucasoid. Such hair can be of any color, straight and very curly, very thin, medium and thick.
• Mongoloid. Such hair is often straight, sometimes wavy, thick, and mostly dark.
• Negroid. This type of hair is curly and varies in thickness.

Hair composition

The chemical composition of hair is well known: carbon, oxygen, nitrogen, hydrogen and sulfur. The main components of hair are keratin and melanin. Keratin, being a dense protein, promotes keratinization of hair cells, and melanin, being a pigment, affects their color. Hair also contains some amount of fatty substances, cholesterol, mineral compounds and arsenic.

Replacing an old hair with a new one occurs when the active cells of the papilla cease to function. The bulb begins to increase in diameter and is gradually pushed out. This is how the hair falls out. At the same time, new active cells are formed in the hair follicle, giving life to new hair. Hair change is a normal natural process if 30-50 hairs fall out on your head per day.

Not only the amount of hair is genetically determined in us. Their color and structure are also determined by heredity. But despite this, the appearance of our hair largely depends on ourselves: what we wash it with, how we care for it, and whether we chose the right haircut. Besides, modern means allow you to curl and straighten hair, change its color, influence porosity and elasticity. In general, no matter what kind of hair nature gives you, 90% of it depends only on you and your efforts whether it will look luxurious or dull.

Human hair is a long, flexible growth that covers the skin in certain areas, such as the scalp. Even in ancient times, head hair and the way it was worn were part of the personality of its owner, which reflected his religious and social role in society. For hair to be attractive, it must look healthy and natural. IN modern society Most women and men also consider hairstyle an important and necessary part of their image.

Human hair structure

The anatomy of a human hair on the skin can be compared to a tree on the ground. IN in this case the tree trunk is a hair shaft, which has a thread-like fibrous structure, and the earth is a follicle, which is a cavity in the epidermis. The follicular cavity has a cylindrical shape and a depth of about 4 mm. Every human hair consists of a root located in the follicle and a trunk located above the surface of the epidermis. The root is thicker than the trunk. The area of ​​the epidermis around the root is called the papillary region, which consists of connective tissue and a network of blood vessels that provide the hair with all the substances necessary for its growth.

As the hair grows, it emerges from its follicle, appearing above the skin surface. That part of the hair in the form of a fiber (stem) that we can observe is dead from a biological point of view. The trunk has a complex structure and consists of a core and a number of outer layers that perform a protective function and are called cuticle.

The cuticle is the outer part of the stem that is constantly under attack from the environment, such as: wind, rain, sunlight, salt water, chemicals, paint and mechanical stress. . It depends on the condition of the cuticle The health of the hair depends. Currently, depending on the type of cuticle damage, there is an appropriate remedy for its restoration.

As mentioned above, the papillary tissue, located at the base of the follicle and providing each villi with nutrients, also requires special care. It lies in balanced diet, containing all the necessary minerals, vitamins and amino acids. Vitamin deficiency or abnormal protein levels, due to poor nutrition or hormonal changes, can interfere with the proper growth of villi and lead to damage to the root structure, which in turn leads to the problem of hair loss.

The structuring of each follicle is such that it has a sebaceous gland, which is responsible for the production of a special sebaceous substance. This substance is a natural lubricant for hair. . Thus, we can distinguish two main parts in the hair structure:

• The outer part, which is called the trunk or rod. It consists of completely keratinized dead cells;
• The subcutaneous or inner part, which is called the root. It consists of living, growing cells. It is the root that allows the villus to grow.

The structure of human hair on the head includes the following components:

The structure of the hair in the figure and the cross-sectional description can be seen in the diagram at the following link:

Properties and composition of human hair

Most important characteristics human hair are as follows:

Chemical composition

Hair is made up of proteins, lipids, oligoelements, water, pigments and other substances.

• 28% proteins;
• 2% lipids;
• 70% water, salts and other substances.

Proteins are found mainly in keratin, which, along with nail keratin, contains more sulfur than in human skin. Keratin itself comes in two types: hard and soft. The first is present in the cortex and cuticle, the second forms the medula.

Life cycle and growth phases

Hair is genetically programmed to complete 25 cycles in its life, with an average duration of each of them being 4 years. The cycle refers to the process of birth, development and death of the villus. In turn, each follicle has its own cycle, independent of the cycles of the surrounding follicles. The average human head has 100,000 villi, and they grow faster in young people than in adults.

The life cycle is usually divided into three main phases:

Hair types and color

The structure of the follicle determines the hair type. So, if it is small cylindrical in shape, then the hair will be thin, but if big size, then thick. If the follicle has a cylindrical shape, then the hair will be smooth, and if it is flat, then it will be wavy.

According to its structure and appearance the following types can be distinguished:

The smooth type is typical for residents of the east, while representatives of the black race have curly hair. Also found mixed type For example, among the inhabitants of the Caucasus, the smooth-wavy type dominates.

What determines hair color

The color of hair is determined by the melanin it contains. There are two types of melanin: eumelanin, which is responsible for dark colors, and pheomelanin, which determines light colors, for example, white or reddish. The mixture of these types of melanin determines natural color hair.

It is also true that the less melanin the hair contains, the more bright hues he will have, that is, a person with black hair contains more of this substance than a blond or blonde. Color is an individual characteristic that is genetically determined in the same way as eye color or skin pigmentation. Not only the quantity and type, but also the shape of the distribution of melanin granules in the keratin cells of the hair shaft (in its cortex) determine the color of the latter.

Ultimately, the color of the hair is determined by a combination of the following factors:

Other factors include the influence of certain medications, poor and unbalanced nutrition, disturbances in normal metabolism, strong emotional arousal, pregnancy in women and others.

All people want to have healthy hair, but not everyone succeeds. This often happens because most people know little about the structure of hair, this truly amazing part of the body.

It must be said right away that every person has tiny hairs all over their body. They do not grow only on the palms, nails, feet, lips and on the sides of the fingers. Body hair is a strictly individual constitutional feature. In some areas of the body the hair is barely noticeable, in others it is only one color.

Functions

Before talking about the structure of human hair, we should touch upon such a topic as the structure of the scalp. In general, the skin covers everything human body, its mass is 5% of the total body mass. The skin consists of several layers:

• epidermis - the top layer consisting of partially dead cells that are washed off during water procedures;
• basal;
• grainy;
• shiny;
• horny.

The scalp performs a number of very important functions, without which the vital activity of the entire organism would be impossible. These include a protective function that protects against the penetration of harmful microbes or other microorganisms into the body. It is the epidermis layer that prevents various types of mechanical damage. The immune function is designed to seek out foreign bodies and deliver them to the sites of neutralization - the lymph nodes. With the help of the receptor function of the skin, a person has the ability to distinguish between tactile and temperature fluctuations and stimuli. Thanks to its metabolic function, the skin has the ability to breathe and also produce secretions that create a thin film on its surface.

The thermoregulatory function ensures that when the temperature rises, blood vessels dilate, and when the temperature drops, the blood flow slows down, and evaporation processes decrease accordingly.

The structure of the scalp and hair is closely interconnected.

In order to have healthy and beautiful hair, you need a strong foundation that would hold them. That is why it is so important to eat properly, well and variedly, saturating your body with useful and necessary substances.

Due to the unsatisfactory environment, most people are recommended to take vitamin and mineral complexes several times a year, which will help to improve and strengthen the skin and hair. In some cases, experts advise taking complexes with a high content of vitamins A and E, for example, vitamin preparations like Aevita.

It should also be remembered that the structure of the hair, its color, growth rate, and the number of follicles are genetically determined by nature, so it is essentially impossible to influence such characteristics. That’s why you can’t blindly trust advertising that promises to make your hair thicker and stronger almost in one go. The main emphasis should be on healthy eating and regular hair care.

Composition and structure

The composition of hair is a large amount of protein called keratin, a certain amount of water, some metals and minerals. In general, hair is a horny skin formation present only in representatives of mammals and homo sapiens. Their structure is best studied using a microscope. Hair has both internal and external parts. In the outer part there are:

1. The core, which contains many non-keratinized cells.
2. The cortical layer is called the cortex. It is this layer that contains a lot of the substance “melanin”, which is responsible for the color of human hair.
3. The outer layer, called the cuticle, is, upon closer inspection, small scales that resemble shingles. In the presence of healthy hair It is this layer that pleases the eye with its brilliance. The cuticle also protects the inside of the hair.

The natural antiseptic, which is included in the fatty lubricant, is designed to protect the cortex from infections. The condition of the hair shaft directly depends on the environment in which a person lives. Various diseases can worsen the condition of the hair, since access to the required amount of vitamins in this case is difficult.

Each hair grows from its own follicle. The root is shaped like a bag. Hair grows as long as its roots, located in the scalp, are alive. A follicle is, in fact, a depression in which such a root is located. It expands downwards and forms a hair follicle. It is to this part of the hair that vessels and glands are connected, providing the processes of nutrition and removal of waste products. On the inside of the follicle there is a hair nipple, consisting of very thin vessels, nerve and connective tissue. It must be remembered that the visible part of the hair is already dead, the living part is located directly under the scalp.

Thickness and amount of hair

Having understood what the structure of hair is, let’s get acquainted with the functions of the hairline.

1. So, the first and main function is protective. Thanks to it, the scalp does not suffer from ultraviolet radiation emanating from direct sunlight.
2. Thermoregulatory function. It is on the human head that hair creates the optimal temperature for the functioning of the brain. During the cooling process, special muscles provide hair lifting, and they prevent the rise of their own heat from the skin.
3. Function of touch. It is the nerve endings on the scalp that give it sensitivity to the slightest changes in the position of the hair. This is especially noticeable if some foreign body appears on the head.

Hair thickness and quantity are strictly individual characteristics. For example, the number of rods can vary from 100 to 150 thousand. The thickness depends on the color. Scientists have calculated that on average, blondes have 50 microns, brunettes have 75 microns, and red-haired people have 100 microns. Hair curliness depends on the location of the follicle in relation to the surface of the head.

Directly related to this are the types of human hair, which can be:

• long;
• Pushkovy;
• bristly.

Another classification subdivides human hair for the following types:

1. Fat. In this case, there is increased activity of the sebaceous glands and excess lubrication. On the scalp there is almost constant greasy shine, hair can quickly become dirty and take on an unkempt appearance.
2. Dry. On the contrary, the activity of the sebaceous glands is low. The skin is dry, the hair shaft is brittle, and the ends of the hair often split.
3. Normal. As the name suggests, in this case the skin condition is balanced.

In some cases, we are talking about “transitional” hair type.

At the same time, as a person gets older, the density of his hairline also changes towards a decrease. To confirm this, it is enough to compare the hair pattern of a young man and a middle-aged man. The length of one hair can reach 1 m. After this, growth stops within 3 months. After this period, new follicles begin to appear. About 3/4 of all hair develops and grows simultaneously, while the remaining 1/4 “rests”. Healthy follicles are very elastic and strong. They can be stretched by 1/5 of their length, after which they return to their previous state. Their strength is comparable to that of a metal such as aluminum. This is why they are able to withstand heavy loads.

In addition, human hair is very hygroscopic in nature, that is, it can absorb moisture quite quickly. Thanks to this, the hair is relatively resistant to the effects of weak acids, but the follicles react poorly to alkalis.

In some cases, human hair can be used as an identifier because it has the ability to accumulate certain substances.

Little tricks when washing

While washing your hair, you need to massage your skin with your fingertips to achieve better blood circulation. This will serve as additional stimulation of the sebaceous glands, which create a natural protective layer on the hair. It is better to use shampoo 2 times.

The first time, try to rinse the scalp itself, and the second time, the hair. It is better to apply the required amount of detergent into the palm of your hand and rub thoroughly so that it is applied evenly over the entire head.