How does the skin protect the human body? Skin is protection

Goals:

Cognitive aspect of the goal:

1. To introduce the concept of "skin", "skin structure" and its functions.
2. Develop the ability to independently research work and transfer the acquired knowledge to new conditions. (At three levels).
3. Continue the formation of concepts: sense organs, hygiene of the human body.
4. To form the ability to use devices for research and cards for independent work.
5. Develop the ability to compare, analyze and summarize information, transfer information to your "life experience", draw conclusions.
6. Continue building a graphic culture
7. Continue the formation of general educational skills:
   Ability to plan one's own activities while fulfilling all independent tasks, when answering questions, during practical work;
   The ability to control one's own activities when performing independent tasks;
   Ability to work in time at all stages of the lesson.

Developmental aspect of the goal:

1. Continue to work on the development of the child's speech:
   work on the word "skin", "hygiene", "research", "elasticity";
   work on phrases: the meaning of the skin, the sense organs, the functions of the skin, the hygiene of the human body;
   work on connected speech with oral answers, the ability to express and prove judgments.
2. Continue to work on the development of attention and thinking.
3. Develop memory, imagination, observation.
4. Develop the ability to work in pairs.
5. Develop creativity, will, cognitive interests.
6. Develop an eye, small muscles of the hand.

Educational aspect of the goal:

1. Continue to work on the formation of conscious discipline
2. continue building relationships in the process joint activities (teacher-student, student-teacher)
3. Continue the formation of moral personality traits
4. To develop sanitary and hygienic skills in caring for the senses.
5. Cultivate the ability to listen to your comrades, and work together.

During the classes

The structure of the skin.

The skin evenly covers the entire body. The skin is made up of three layers.

The first layer is the outer shell on top, which protects our skin from damage. It contains pores through which the skin breathes.

The second layer is the skin itself. It contains sebaceous glands that lubricate the skin and hair. The sebaceous glands secrete fat. Fat coats the skin and makes it softer. Sweat glands are located all over the surface of the skin. Sweat evaporates from the surface and the human body cools down. The secretion of sweat regulates the temperature. The skin contains blood vessels and nerves. Therefore, the skin is very sensitive to cold, heat, pain.

The most sensitive skin is on the tips of the fingers, nose, middle of the palms and along the midline of the back. Hair and nails grow on the skin.

The third layer is subcutaneous fat. It protects the skin from bruises and retains heat.

The skin is a reliable protection.

The skin is a reliable protection. The skin is waterproof, so the person does not dry out in the heat and does not "melt" during the rain.

The skin protects a person from solar radiation.

It is strong enough to protect him from damage, while at the same time soft and resilient enough to allow a person to make movements.

It retains heat when needed, cools the body, maintaining a constant temperature inside it.

With sweat, a large amount of harmful substances are released from the human body. When a lot of fat and sweat accumulate on the skin, dust sticks to them. So the skin becomes dirty. Microbes begin to multiply on the skin. There are up to 40,000 microbes per square centimeter of skin. If you do not monitor the cleanliness of the skin, then there may be skin diseases. Therefore, the skin must be kept clean.

Skin care.

Washing is the main way to take care of your skin. Then dust, microbes, fat, sweat are removed from the skin. Wash your skin 1-2 times a week. Scientists have calculated that washing with soap and a washcloth removes up to 1.5 billion microbes from the skin. Be sure to wash your face, hands, feet, neck every day. Armpit skin.

With normal skin, you need to wash your face daily. Wash with soap 2-3 times a week, as frequent washing with soap degreases the skin. You can not wash your face with cold water all the time, as the vessels narrow and the skin becomes dry and pale, flabby, wrinkles appear. You can not wash yourself with very warm water all the time. Hot water cleanses the skin well, causes vasodilation, then the skin becomes weaker. Be sure to dry your skin with a towel.

Exercise 1.

1. Read the text "The structure of the skin."
2. Underline with a green pen how many layers the skin consists of and what they are called.
3. Underline the answers to the following questions in pencil:
   In which layer of the skin are pores located?
   What glands are in the second layer?
   What protects the skin from damage and retains heat?

Do exercises for the eyes.

Task 2.

1. Read the text "Skin is a reliable protection."
2. Underline with a simple pencil how the skin protects the body.

Task 3.

1. Read the text "Skin Care"
2. Underline skin care rules with a simple pencil.

Task 4.

Run a test. Highlight the correct answer.

1. The skin is an organ
   a) hearing
   b) touch;
   c) sense of smell.
2. The skin breathes through:
   a) pores;
   b) hairs;
   c) fat.
3. The skin is made up of three layers:
   a) outer shell, fat, skin;
   b) outer shell, skin, subcutaneous fat;
   c) fat, sweat, pores.
4. To keep the skin free of microbes, it is necessary:
   a) wash the whole body with soap and a washcloth at least once a week;
   b) lubricate with cream.
5. Which skin care items are listed correctly:
   a) toothbrush, toothpaste, chewing gum;
   b) washcloth, soap, towel, cream;
   c) shoe polish, shoe brush, glue.

The skin protects the body of humans and animals, is a barrier between the body and the external environment. It has a complex structure and performs various functions. It forms a separate organ with its own blood supply, innervation, inherent. The skin area of ​​an adult is about 2 square meters and depends primarily on height and body weight.

The weight of the skin is equal to 15% of the mass of the human body.

On different parts of the body, the thickness of the skin varies. The skin can have a thickness of 0.5 to 5 mm. On its surface there is a specific pattern of triangles and rhombuses forming a grid. It is especially visible on the fingers, palms, soles.

Human skin is only 70% water, it is denser than many other organs. In this article we will tell you how the human skin is arranged, what are its functions.

How is the skin

The skin has a layered structure. It includes:

• epidermis;
• the skin itself, or the dermis;
• hypodermis (fatty tissue).

The epidermis is the topmost layer, it is represented by several layers of epithelial cells. The cells of the lower layer of the epidermis are constantly dividing, providing rapid recovery and skin renewal. The closer the cells are to the surface, the less they multiply and the more keratin and other dense proteins they contain. On the surface of the epidermis are keratinized cells, which are constantly. So there is a constant renewal of the skin.

The epidermis of an adult is completely renewed in two months, an infant - in three days.

The upper, stratum corneum of the epidermis protects the skin from damage. It is thickest on the soles and palms. The thinnest epidermis is located on the eyelids and the skin of the male external genitalia.

The epidermis does not allow cosmetic products based on collagen and elastin to pass through it due to too large sizes these molecules.

The dermis is the middle layer of the skin, made up of connective tissue. It includes thin bundles of elastic tissue, collagen, muscle fibers. Nerve endings are located in the dermis. In the same layer there are a large number of arteries, veins and lymphatic capillaries that feed not only this layer itself, but also the epidermis, devoid of blood vessels.

Vessels of the skin are able to accommodate a third of the entire blood of the body.

The hypodermis is represented by a network of fibers, between which there are fat cells. It helps protect the organs under the skin from damage. The thickness of adipose tissue is different: on the scalp it is 2 mm, and, for example, on the buttocks it reaches 10 cm. There are many vessels and nerves in adipose tissue. The sweat glands and hair follicles are also located here. The ducts of the sebaceous glands open at the mouth of the hair follicles.

Skin, nails and hair are almost completely formed by the 7th month of fetal development.

Skin functions

Protective

The skin protects the underlying tissues from bruises, pressure, stretching. The epidermis does not give tissues.

In addition, it prevents various chemicals from the external environment from entering the body. contained in the skin absorbs ultraviolet radiation from the sun. Skin has antimicrobial properties. The epidermis is impenetrable to many pathogens. Sweat and sebum create an acidic environment in which many microbes die.

Beneficial microbes also exist on the surface of the skin, protecting it from pathogenic bacteria, so the absolute sterility of the skin is harmful.

Thermoregulating

The skin is actively involved in heat transfer. If the external environment has a high temperature, the vessels of the skin expand, enhancing heat transfer. At the same time, heat is lost through sweat. At a low temperature of the environment, the vessels of the skin spasm, preventing heat loss. Thermoreceptors are involved in the regulation of this process - sensitive "temperature sensors" located in the skin.

Per day in normal conditions a person loses up to a liter of sweat, in the heat this amount can reach 5 - 10 liters.

excretory

With sweat, excess salts, some toxins, as well as medicinal substances come out through the skin.
Urea, uric acid, acetone, bile pigments and other metabolic products pass through the skin. These processes are especially noticeable in diseases of the kidneys and liver, which normally remove these toxins with urine and bile. At the same time, the skin of the patient begins to emanate bad smell to help physicians diagnose.

Receptor

The epidermis contains tactile cells. Their superficial location causes high tactile sensitivity. Special nerve formations provide sensitivity to cold, heat, position in space, pressure and vibration. Pain, burning and perceive free nerve endings located in the upper layer of the skin.

Thermoreceptors perceive temperature in the range of +20 - +50˚С, at lower and higher temperatures, the impact is most often perceived as pain. A person feels cold much better than warm.

Regulatory

The skin carries out the synthesis and accumulation of vitamin D and some hormones.

Vitamin D can only form on the surface of the skin, from which the layer of sebum has not been washed away, and it should not be tanned.

immune

Langerhans cells (tissue macrophages) penetrate into the epidermis from the bone marrow, capable of mobilizing immune cells (T-lymphocytes) to fight external damage (antigen). The cells of the surface layer of the skin are actively involved in the reactions of humoral immunity, contributing to the production of antibodies. All of these mechanisms contribute to strong skin immunity.

The skin is one of the immune organs along with the lymph nodes, bone marrow and thymus gland.

Secretory

The skin glands secrete 20 grams of sebum per day. It ensures the elasticity of the epidermis, and together with sweat creates a protective environment on the surface layer of the skin.

Most of the sebaceous glands are on the skin of the face, scalp, between the shoulder blades, in the center of the chest, and also in the perineum. It is these parts that most often suffer from acne and.

So, human skin is an amazing organ that shelters and protects it from an aggressive external environment. Skin care will help not only prolong its beauty, but also maintain the health of the whole organism.

Among all other organs - the skin is the largest, the area of ​​\u200b\u200bthe skin is from 1.5 square meters. m to 2 sq m, the weight of the skin is 5% of the weight of the human body. Acting as a living border barrier, the skin is negatively affected from both sides, it is exposed to exogenous influence (from the outside) and the action of internal toxins and poisons that the body produces in the process of life.

Therefore, a person is taught to monitor the condition of the skin and take care of it from childhood: hygiene rules, a balanced diet, sports and other factors allow you to maintain healthy skin and eliminate many risks in life.

Protection against mechanical stimuli

The stratum corneum is a dense membrane that protects internal organs and muscles from mechanical damage. The skin reduces and weakens pressure, impacts, friction and other influences, and in places of constant contact with mechanical stimuli it coarsens, keratinization in the form of calluses is formed on it, which is a natural change in the structure of the skin and protects the tissues located inside from damage.

Excellent resistance to mechanical stress and subcutaneous tissue. It is elastic and mobile, thanks to these properties it takes an active part in protecting the internal organs and tissues under the upper layer of the skin from damage.

Collagen fibers are a natural protection of the skin from ruptures, their resistance to rupture is 43 times higher than that of elastic ones. Therefore, the more collagen in the skin tissues, the higher the resistance to mechanical stress.

The negative effect of electromagnetic waves reduces melanin - a skin pigment, it is synthesized under the action of ultraviolet and X-rays.

The appearance of sunburn is a protective pigmentation or absorption of harmful radiation by the upper layer of the skin, the stratum corneum has the same property. It also protects the internal fibers from electric current, since in stratum corneum contains air, this makes the layer less electrically conductive than deeper and thinner layers.

Ionizing radiation or radioisotope penetrates the body much less if the integrity of the skin is not broken. Healthy skin prevents the penetration of radioisotopes, and if the radiation intensity does not reach the maximum allowable doses, then everything can be done without unpleasant consequences.

Resistance to chemical irritants

Chemical aggressive environments affect the human body, getting into it through the skin. To protect yourself from the penetration of carbon dioxide, hydrogen sulfide and other substances that interact with lipids into the internal organs, the skin must be protected from damage. You need to beware of getting into the body of iodine, alcohol, chloroform, ether, phenol, tar, poisonous weapons.

It is the skin that puts a barrier to the deep penetration of these harmful compounds and saves from death along with personal protective equipment.

Lipids provide inhibitory action, and quality characteristics the permeability of the skin increases, it does not allow the penetration of harmful aqueous solutions and toxic gaseous substances into the body. There is a neutralization of such compounds as salts, alkalis, this is facilitated by sweat and sebaceous glands and the stratum corneum. In addition, the protective function against chemical reagents enhances the keratin contained in the skin cells. It is resistant to alcohol, acids, alkalis, ether and other chemicals harmful to humans.

The surface layer of human skin is covered with a large number of microscopic organisms, since there are a great many of them in the environment. The presence of harmful bacteria and microbes, even on healthy skin, is in the billions..

The task of the skin is to prevent these biological contaminants from entering the human body. the more impenetrable, the rougher the surface layer. For example, the stratum corneum perfectly resists microbes, the skin of an adult, being denser, better protects it from biological effects than the skin of children, which is much thinner. Using the procedures of exfoliation of the stratum corneum, a person, together with keratinized particles, removes microbes from the surface of the skin. Great importance has a regenerative ability of the skin, it lies in the fact that all impurities, including biological ones, are removed from the body naturally through the pores, with sweat and sebaceous secretions.

We present to you Interesting Facts about human skin, which you probably did not know about.

The skin covers the entire human body and is the largest organ of the human body, which has a variety of functions and is closely related to the entire body.

The value of human skin is enormous. It is the human skin that directly perceives all environmental influences.

First, there is a reaction of the skin to any negative impact, and only then of the whole organism. The surface of the skin contains numerous folds, wrinkles, grooves and folds, forming a characteristic relief that is purely individual and persists throughout life. Here are some facts about human skin.

♦ About 70% of human skin is water and 30% is proteins (collagen, elastin, reticulin), carbohydrates (glucose, glycogen, mucopolysaccharides), lipids, mineral salts (sodium, magnesium, calcium) and enzymes.

♦ People have different height, fullness, respectively, and skin area different people will differ, but on average this figure is at the level of 1.5-2.5 m2.

• The weight of the multi-layered skin is over 11-15 percent of a person's weight.

skin function

Its main function is protective.

• protective function against overheating of the body and mechanical damage, from radiation, including the ultraviolet part of the light spectrum, from microbes and harmful substances;
• the function of regulation through the mechanism of sweating equilibrium in terms of the amount of water, the presence of certain substances;

• through the skin, the body and the environment exchange the necessary substances, the skin is to some extent an auxiliary respiratory organ;
• Under certain conditions, the skin can serve as a synthesizer of useful substances. For example, when sunlight hits the skin, complex processes, which contribute to the synthesis of vitamin D. From this point of view, sunburn is useful, but one should not forget about the properties of ultraviolet rays that are detrimental to all living cells, an amazing fact;
• tactile function: receptors are built into the skin, due to them a person has a sense of touch;
• appearance shaper function: features of the skin of the face and subcutaneous mimic muscles allow you to visually distinguish one person from another and convey your emotions.

♦ The structure of the skin. The skin consists of three layers, the upper layer is the epidermis, the middle layer is the dermis and the lower layer is the hypodermis (subcutaneous fatty tissue).

Epidermis

The epidermis is approximately 10.03-1 mm thick. Every three to four weeks, this layer of the skin is renewed, this is due to the deepest layer of the epidermis - the basal, in this layer of creatine - a very important protein for the skin - new cells are formed. Within a few weeks, these cells rise to the surface of the epidermis. By the end of their journey, they become dry, flat and lose their cell nucleus. Amazing facts about human skin!

The epidermis or outer layer covers the dermis and is the surface of the skin with bulges and depressions, includes approximately 15 layers. This is the epithelium, constantly created by the basement membrane layer. The epidermis is divided into 3 layers. The outer or stratum corneum, strong and impermeable to water, consists of dead cells that are constantly separated from the epidermal layer by small scales under the action of new cells originating from the inner layers.

The middle layer of the epidermis contains adult (scaly) cells that renew the outer layer, human skin facts. The middle layer or basement membrane layer creates new cells, which usually develop into squamous cells. The basement membrane layer also contains melanocytes, the cells that produce the melanin pigment.

Sun exposure stimulates the production of melanin to protect the skin. That is why after exposure to the sun a tan appears. Some fake tanning creams stimulate the formation of melanin, others contain a component (dihydroxyacetone) that gives the skin a red-brown color, similar to a tan, fact!

Facts about human skin. Dermis

The dermis is the main layer of the skin. The dermis is rich in connective fibers (75% of the structure) that maintain the elasticity (elastin) and resistance (collagen) of the skin. Both substances are extremely sensitive to solar (ultraviolet) rays, which destroy them. Cosmetics based on elastin and collagen cannot restore them, because their molecules are too large and cannot pass through the outer skin. In the dermis there are receptors that perceive various external stimuli.

Hypodermis

This layer includes adipose tissue, subcutaneous nerve and vascular channels. The hypodermis also contains hair follicles and sweat glands.
♦ Color of the skin, sexual and racial characteristics are possible due to the distribution of four main components on the surface of the skin:
- melanin, a brown pigment - carotene, the color of which varies from yellow to orange
- oxyhemoglobin: red
- carboxyhemoglobin: purple

Skin color is affected by genetic factors, environment (sun exposure) and nutritional factors. The complete absence of the first two pigments causes albinism.

♦ Freckles most often appear in adolescence and almost disappear by the age of 30. They don't darken randomly.

The presence of freckles means that in the human body it will reduce the level of melanin, a photoprotective pigment. That is, freckled skin is most vulnerable to harmful ultraviolet radiation. Therefore, people with freckles are strictly recommended to smear protective cream and avoid overly revealing clothing. One can only wonder at such amazing facts about human skin.

♦ Skin thickness varies depending on the areas under consideration from 0.5 mm to 2 mm on the palm and sole.

• In a baby, the thickness of the skin is one millimeter. As it grows older, it remains thin only on the eyelids. In an adult, the average value of skin thickness increases several times.
• The skin has a significant resistance to stretching.
• The thinnest skin is on the eyelids and eardrums - from 0.5 mm and thinner, but the thickest is located on the feet, here it can reach a thickness of about 0.4-0.5 cm.

♦ Nails and hair also belong to the skin - they are considered its appendages, a fact!

♦ The skin has about 150 nerve endings, about 1 kilometer of blood vessels, more than 3 million cells and about 100-300 sweat glands.

♦ Vascular system skin contains a third of all blood circulating in the body - 1.6 liters. The skin tone also depends on the state of the capillaries (they are expanded or narrowed) and their location.
♦ Sweat glands act as a temperature controller.

• Approximately in every square centimeter of human skin there are about a hundred sweat glands, 5 thousand sensory points, six million cells, as well as fifteen sebaceous glands.
• Their total number is from two to five million, most of these glands are located on the palms and feet, approximately 400 per square centimeter, followed by the forehead - about three hundred per square centimeter.
• Asians have fewer sweat glands than Europeans and Africans.
• Human skin releases about 1 liter of sweat per day.

♦ Skin cells in the body, there are from 300 to 350 million. During his life, each person loses up to a hundred kilograms of horny scales, which turn into dust. Wow facts about human skin!

• In a year, the body must produce more than 2 billion skin cells. The fact is that during the year the change of all skin cells occurs at least 6 times (complete replacement - in 55-80 days). The process of completing the cell cycle occurs at a rate of 0.6 million horny scales / hour (this amount corresponds to a weight of 0.7-0.8 kg).
• In a lifetime, a person renews the skin about 1000 times.
• The skin that a person sheds over a lifetime weighs up to 18 kilograms.
• Skin cells are renewed more and more slowly with age: in newborns every 72 hours, and in people from 16 to 35 years old, only once every 28-30 days.

♦ In one day, the sebaceous glands of the skin produce approximately 20 grams of sebum. After that, the fat is mixed with sweat and forms a special film on the skin, which protects it from fungal and bacterial damage.

• The number of sebaceous glands depends on the area of ​​the body. There are few of them on the back of the hands, and on the T-zone of the face (forehead - wings of the nose - chin), under the hair on the head, in the ears, as well as on the chest and between the shoulder blades, they can be from 400 to 900 per 1 sq. cm. It is there that acne and the so-called black dots appear - comedones, by which you can identify a clogged pore.

♦ On the surface of the skin there are colonies of beneficial microorganisms that help in the fight against pathogenic bacteria.

If you achieve absolute sterility, you can weaken the double protection: excessive sterility is harmful to the skin.

• For one sq.cm. The skin contains 30,000,000 different bacteria.

♦ On the skin of an adult, on average, there are from 30 to 100 moles, but sometimes their number can exceed 400. British scientists saw this as a connection with the speed with which the body ages.

According to the results of the study, the number of moles is proportional to the length of telomeres - the end fragments of chromosomes that shorten with each cell division. There is a hypothesis that people with many moles are less likely to suffer from age-related diseases.

♦ The skin ages due to ultraviolet radiation, stress, lack of sleep, reduction of collagen and fibroblasts.

♦ The smoothness of the skin depends on the condition of the collagen. In a young body, its cells are twisted, which makes the surface of the skin more stretched and smooth. With age, from lack of nutrition and poor water, collagen cells are filled with heavy metals and straighten, and skin tone decreases.

• Collagen makes up 70% of the dry dermis and decreases by 1% every year.

♦ Vascular networks or asterisks can occur if there is a lack of vitamin D in the body, this disease occurs in 90% of people, therefore good nutrition is necessary for good skin.

♦ Leather waterproof provides its outer layer of the epidermis. Its cells are in very close contact with each other and have a layer of fat on the outer surface.

If the body is in water for a long time, the extracellular layer of fat becomes thinner and water gains access to the skin cells, as a result, it swells. Have you seen how the skin of your fingers wrinkles in the water? This transformation serves to improve traction (just like treads in car tires).

♦ Flaccid skin syndrome is a rare connective tissue disease in which the skin easily stretches and forms loose folds.

In flaccid skin syndrome, mainly elastic fibers are affected. The disease is usually hereditary; in rare cases and for unknown reasons, it develops in people who do not have precedents in the family.

Some hereditary forms are quite mild, others are accompanied by some degree of mental retardation. Sometimes the disease leads to death.

With sluggish, flabby skin, it easily gathers into folds and hardly returns to its previous position.

In hereditary forms of the disease, excessive skin folds already exist at birth or form later. The "excess" and laxity of the skin is especially evident on the face, so that the sick child has a "mournful" look. A hooked nose is typical.
In general, flaccid skin syndrome is a pathology of the connective tissue. Unthinkable facts about human skin.

Since the connective tissue is part of all body systems, the manifestations of the syndrome are very diverse. Both the osteoarticular, and pulmonary, and cardiovascular, and digestive systems are affected.

Treatment has not been developed. In people with a hereditary form of the disease, reconstructive surgery significantly improves appearance. However, excess skin can form again. Reconstructive surgery is less successful in the case of an acquired form of the disease.

Here are some amazing facts about human skin.
According to videoplastica.ru, popular-medicine.rf

50 facts about our skin (brief summary)

1. Skin is the largest organ in the human body
2. If you stretch the skin of an average person, it will cover an area of ​​2 square meters
3. Skin makes up about 15 percent of your body weight.
4. There are two types of skin: hairy and hairless

5. Your skin has three layers:
-epidermis - water-repellent and dead layer
dermis - hair and sweat glands
subcutaneous fat - fat and large blood vessels

6. Every inch of your skin has a certain elasticity and strength, depending on the location. So the skin on the knuckles is different from the skin on the stomach.
7. Scar tissue lacks hair and sweat glands
8. The thinnest skin on your eyelids is about 0.2 mm
9. The thickest skin on your feet is about 1.4 mm.

10. A person has an average of 100,000 hairs on his head. In people with blonde hair about 140,000 hairs, dark-haired - 110,000, and red-haired about 90,000.

11. Each hair has a small muscle that lifts the hair in cold and various emotional states.
12. Body hair grows 2 to 6 years
13. We lose 20 to 100 hairs per day.

14. Keratin forms the outer dead layer of the skin and nails.
15. More than 50 percent of the dust in the house is made up of dead skin.
16. Every 28 days your skin is renewed.
17. Lipids are natural fats that keep the outer layer of skin hydrated and healthy. Detergents and alcohol destroy lipids.

18. Skin sheds over 30,000 dead cells every minute.

19. As we age, we begin to shed less skin. In children, old cells are shed faster. This is why babies have such a pink fresh complexion

20. The skin produces about 500 ml of sweat per day.
21. Sweat itself is odorless, and it is thanks to bacteria that body odor is produced.
22. Your skin is a microcosm of over 1,000 species of bacteria and about 1 billion individual bacteria.
23. The glands that produce earwax are special sweat glands.
24. On average, you have about 14 types of fungi living between your toes.

25. Skin color is the result of a protein called melanin. Huge skin cells in the form of tentacles - melanocytes, produce and distribute the pigment melanin.

26. People have the same number of melanin cells. Different skin color is the result of their activity, not quantity.
27. Human skin varies greatly in different parts of the world. According to the well-known classification - the Lushan scale, there are 36 basic types of human skin color.
28. 1 in 110,000 people is albino, meaning they don't have melanin cells.
29. Melanin is also responsible for the color of the eyes, and the skin itself that covers the eye is transparent and very sensitive.
30. Permanent skin color in a child is formed within about 6 months.

31. The cause of acne or pimples is the overproduction of cells that line the sweat glands.
32. Even babies suffer from acne. Some newborns develop acne in the first few weeks of life. The cause of acne in newborns is not fully known, but it does not require treatment and goes away on its own.
33. About 80 percent or 4 out of 5 teenagers experience acne.

34. But this is not only a problem of adolescence. One in 20 women and one in 100 men suffers from acne in adulthood
35. The appearance of a boil is associated with a staphylococcal bacterium. It penetrates into tiny cuts in the skin, getting into the hair follicles.

36. The look and texture of your skin speaks volumes about your health. With illness, the skin turns pale, and with fatigue, bags under the eyes appear.
37. Smoking negatively affects the condition of the skin, depriving it of oxygen and nutrients, slowing down blood flow, and also contributing to the appearance of wrinkles.

38. The skin heals very quickly. Since the top layer of the skin is a living tissue, the body begins to heal the wound immediately. Blood from a cut forms a scab and seals the wound.

39. Most moles are genetically predetermined even before we were born.
40. People who have more moles on their bodies live longer and look younger than those who have fewer moles.
41. Almost every person has at least one mole.
42. Moles can appear anywhere, including the genitals, scalp and tongue.
43. Freckles most often appear in people with fair skin color.

44. Freckles turn pale in winter, since melanin is not produced in in large numbers during the winter months.
45. Freckles can be red, yellow, light brown and dark brown.
46. ​​Unlike moles, freckles do not appear at birth, they appear after a person has been exposed to sunlight.

Facts about human skin. What vitamins are needed?

47. Vitamin A heals skin from sun damage and cellulite
48. Vitamin D - reduces rashes and growths
49. Vitamin C - antioxidant, restores vitamin E and protects from the sun
50. Vitamin E - antioxidant, protects against sun damage and aging.

Municipal state educational institution

secondary school №9

named after Nikolai Kuzmich Kalashnikov

Technological map of the open lesson

Appendix 1.

Reception "True and False Statements" involves a series of statements on a particular topic. Students choose "true" statements based on their own experience or intuition.

Appendix 2

Table "Z-X-U" ("I Know - I Want to Know - I Learned")

One of the ways of graphic organization and logical and semantic structuring of the material. The form is convenient, as it provides an integrated approach to the content of the topic.

Step 1: Before getting acquainted with the text, students independently or in a group fill out the first and second columns “I know”, “I want to know”.

Step 2: In the course of acquaintance with the text or in the process of discussing what they have read, students fill out the “Learned” column.

Step 3: Summing up, comparing the contents of the graph.

Additionally, you can offer children 2 more columns - “sources of information”, “what remains undisclosed”.

Questions for the game:

1) ... what is the purpose of the skin?

2) … what does the skin secrete?

3) ... what are pores?

4) … what kind of skin care products do you have?

5) ... what first aid should be done for skin lesions?

6) ... what remedy helps with wounds?

Appendix 3

Appendix 4

Sample lesson analysis.

The program "School of Russia", the subject "The world around us", the author of the teaching materials - A.A. Pleshakov, class -3, lesson type - learning new, topic " Reliable protection organism."

Preparing the teacher for the lesson: notes, blackboard design, didactic cards, devices for practical work, presentation.

Target:the formation of students' knowledge about the meaning of human skin, its properties, the development of first aid techniques for minor skin injuries, the development of logical thinking.

Planned results : use knowledge about the structure and life of the human body to preserve and strengthen your body, provide first aid for minor skin injuries, extract the necessary information, express your thoughts with sufficient completeness and accuracy in accordance with the tasks and conditions of communication.

UUD: selection necessary information; establishment of causal relationships; the ability to express one's thoughts with sufficient completeness and accuracy in accordance with the tasks and conditions of communication.

Various technologies were used at the lesson: health-saving, ICT, group, system-activity approach. Teaching methods and techniques (partial search or problematic, research, project method, illustrative and explanatory) correspond to the objectives of the lesson.

The first stage of the lesson is the motivation of students' learning activities. When updating the assimilation of knowledge, the tasks correspond to the content setting of the lesson. At the stage of self-determination of activity, through a problematic issue, students formulated the topic and objectives of the lesson. Work on the topic of the lesson is built both in the joint discovery of new knowledge through research work (comparison, highlighting the main thing, classification) and through independent work of students, as one of the main activities (when checking homework, preparing for the assimilation of new knowledge, while consolidating new material). Forms of organization of independent work: individual, pair, group. Frontal conversation completes each stage of the lesson with a conclusion, formulation of the main concepts, inclusion of new knowledge in the knowledge system. The lesson develops the skill of self-control and self-esteem. Types of checks: self-control and mutual control through feedback. After checking the work - analysis common mistakes. Self-evaluation of students is followed by teacher evaluation, reflection of activity. The structure of the lesson complies with the requirements of the Federal State Educational Standard, the tasks set have been achieved.