Presentation on the topic of skin as a border guard of the body. Presentation on the surrounding world on the topic “Skin is the “border guard” of the body” (grade 4)

“The skin is the “border guard” of the body”

Target:

To form a concept about the structure and functioning of the human body.

Tasks:

To create conditions for students to develop an understanding of human skin as the outer covering of the body, its properties, structure, functions and their relationships.

Develop the ability to conduct self-observation and implement hygienic skills in skin care, prevention of damage and first aid in case of violation of its integrity.

Cultivate neatness and respect for your body and health.

Equipment : support cards on the structure of the skin, magnifying glasses, tracing paper, sheets - instructions for six groups.

Lesson structure.

I. Organizational moment (~1 min.).

II. Updating knowledge and problem statement (~3 min.).

1. Intellectual warm-up.

2. Problem situation.

III. Collaborative discovery of knowledge (~27 min.).

1. Working with the textbook.

Physical education (~2 min.).

2. Practical work.

3. Work in groups.

IV. Independent application of knowledge (~4 min.).

V. Summing up the work (~2 min.).

VI. Reflection on activity (~1 min.).

VII. Homework (~1 min.).

During the classes

I. Organizational moment.

- Hello, golden sun,

Hello, the sky is blue,

Hello, free breeze,

Hello, little oak tree.

We live in our native land.

I greet you all!

II. Updating knowledge and problem statement (~4 min.).

1. Intellectual warm-up.

– Guys, probably each of you wants to be strong and healthy. How do you understand the term “health”? (Children express their opinions.) (This is the state of our body.)

– Health is one of the most important human values. No wonder people say: health is more valuable than gold. In order for a person to be completely healthy, it is necessary that all organ systems of his body work properly.

– What organ systems are distinguished in humans? (Musculoskeletal, digestive organs, respiratory organs, excretory organs, circulatory organs, reproductive organs, sensory organs.)

– What organs are sensory organs? (Eyes, nose, tongue, ears, integumentary organs (skin and mucous membrane).

– What role does integumentary tissue play in the body? (The integumentary tissue performs two functions: protective and tactile. Protective function, since it prevents the invasion of various harmful influences into the internal environment of the body. The tactile function helps to notice in time and prevent the danger of invasion of foreign objects and phenomena into the internal environment of the body.)

– What coverings protect the body of animals: amphibians, reptiles, birds and animals? (The chitinous cover of arthropods and the horny scales of reptiles protect their owners from mechanical damage and drying out. The feathers of birds and animals, in addition, protect them from heat loss and overheating during extreme heat. The huge role of the skin in the gas exchange processes of amphibians is associated with its barrier function. )

2. Problem situation.

– A person who has a large area of ​​skin affected by a burn may die if living skin cannot be transplanted. Why? (Children make hypotheses.)(Various microbes enter internal organs.)

– Try to formulate our task in class. (We will figure out what skin is and why it is so important for humans.)

III. Collaborative discovery of knowledge.

1. Working with the textbook.

– Open the textbook on p. 7 and read the title of the paragraph. How do you understand it? (Read the title.)

(They put forward versions.)(A border guard is a person who serves to guard the borders of a country and makes sure that no one can enter its territory. Probably, the skin in our body also makes sure that no one gets into our body. It protects internal organs from entry of various microbes into it.)

– The thickness of the skin is only 2 millimeters, but with a strong magnification (about 50 times) you can see its structure.

– How is the skin designed to perform such an important role? Look at the picture on p.7 (Children look at how the skin works.)

– How many layers of skin are there and which ones are highlighted? (Skin consists of several layers of living cells:

o external;

o internal;

o fatty.

The figure highlights:

o outer layer of skin made of dead cells;

o inner layer;

o fat cells;

o blood vessels.

(As they are voiced, similar cards are posted on the board.)

– Read the dialogue between our heroes Lena and Misha. Define the role of the outer layer of skin.

– What is the role of the outer layer? (Protects living cells throughout the body.)

– What is located in the inner layer? (hair follicle, hair root, sebaceous gland, sweat gland.)

Physical education minute.

2. Practical work.

– Let’s determine in practice what kind of skin we have? Use the words written on the board to answer. (On the board there are words for reference: smooth, motionless, elastic, elastic, cold, even, hard, soft, has a pattern, has folds. The list includes “extra” words that are not suitable for describing the properties of the skin.)

1. Pull the skin on your hand with your fingers and release. What happens to the skin? Why? What kind of skin? (Words for reference are given on the board: smooth, motionless, elastic, elastic, cold, even, hard, soft, has a pattern, has folds.)(The skin has a pattern, stretches well, contracts and returns to its original shape. It is soft and elastic.)

2. Examine the skin through a magnifying glass. What do you see? (The surface of the skin is uneven, there are folds, and holes are visible on the surface. These are called pores.)

– What is the purpose of pores? (Through them the skin breathes, oil and sweat are released through the pores.)

3. Examine the skin on your fingertips. What did you notice? (They have grooves on them.)

– As a result of observations, it was found that the pattern of grooves on the fingers - papillary pattern - is different for each person. It forms on the skin before the baby is born and lasts a lifetime. This observation is widely used in forensic science, where fingerprints of the alleged criminal are compared to prove a crime has been committed.

4. Run your finger across your forehead and press your finger onto the tracing paper. What's left on it? (A patch of oil that is released through the pores. Oil acts as a lubricant, so our skin remains soft and supple.)

5. Having such a structure and properties, what role does the skin play? Find the answer in the textbook and complete task 1 on p.8. (Work in pairs of constant composition.)

– What other role does our skin play? (Keeps a constant body temperature - thermoregulation.)

– Scientists have calculated that if the human body did not have such a regulation system, then within 12 hours the blood temperature would reach the boiling point.

(Skin is an organ of touch.)

– Why is skin called our natural clothing? (Skin and clothing perform similar functions: they protect and protect our body.)

VI. Reflection of activity.

(I give an assessment of the children’s work in class.)

– If you think that in the lesson you have gained vital knowledge and skills, then clap, but if you think the opposite, then do not clap.

VII. Homework.

– At home, you will re-read the material §2, answer the questions with an asterisk on p. 10, complete the tasks on p. 12 (optional).

Ι. Updating knowledge and setting educational problems.

Discussion of creative issues from the last lesson (intellectual warm-up).

– A person who has a large area of ​​skin damaged as a result of a burn may die if living skin cannot be transplanted into him. Why?

Hypotheses are made:

The skin protects our body, breathes, and releases harmful substances. A person dies because these processes are disrupted.

– Read the dialogue between Lena and Misha on p. 12. What are they talking about? What question do you have?

– How can dead cells protect our body?

– What will we talk about in class today? (About skin.)

– What knowledge will be useful to us?

1. What parts does the animal’s body consist of? person?

2. What is the smallest part of a living organism called?

3. What role does integumentary tissue play in the body? in which organisms

is it available?

4. How do the covers of amphibians, reptiles, birds and animals differ?

5. What is the role of feathers and wool in the life of birds and animals?

– Let’s draw up a work plan based on these questions.

Plan

The teacher together with the children draws up a lesson plan.

- What were we doing with you now? (We were planning our activities.)

-What skill did you develop?

ΙΙ. Collaborative discovery of knowledge.

1. Conversation.

- Let's get acquainted with the structure of the skin. Look at Fig. us. 12.

– How many and what layers of skin are highlighted? (Two layers, outer and inner, and adipose tissue.)

– What is the role of the outer layer? (It protects the cells of the inner layer.)

– What is located in the inner layer? (Living cells. This layer contains: hair follicle and hair, sebaceous and sweat glands, nerve endings.)

– What do we find in all layers of the skin? Why? (Blood vessels - along them

nutrients and oxygen are transferred; nerve endings - they perceive various sensations.)

2. Practical work.

- Let's determine what kind of skin we have. To do this, let’s conduct an observation: pull the skin on the hand (arm) with your fingers and release, squeeze and release. What

what happens to the skin? Why?

They do the work.(The skin is soft, elastic, stretches well, contracts and returns to its original shape.)

3. Working with the textbook.

– You have become familiar with the structure and properties of skin. What role does it play? Look at the pictures and complete the tasks on p. 13, 14.

(The skin protects the body from friction, shock, penetration of harmful substances or microorganisms, and drying out.)

– How do we answer the lesson question? (The dead cells in the outer layer of the skin protect the living cells in the inner layer, which have a very important role in the body.)

– How do you understand the title of the lesson topic: “The skin is the “border guard” of the body”?

(The skin protects the body from the penetration of harmful substances and microbes into it; excess salts and water are released through the skin.)

– Who will find the correct answer to this question faster? ( Working with the textbook text on p. 14.)

– How does the skin protect our body from overheating? (The skin maintains a constant body temperature: the sweat glands work, and as sweat evaporates, the body cools.)

– Why do we need hair and nails? (Hair protects from overheating and hypothermia, nails protect sensitive fingertips.)

– What replaces sight for the blind? (Skin is an organ of touch. In its inner layer there are sensitive nerve endings that perceive all surface irregularities.)

– What was the level of the task?

– Now we are together with... (student's name)

- What were we doing now?

– What skills did you develop?

ΙΙΙ. Independent application of knowledge.

1. Work in the textbook.

1. Discussion of questions 1–4 on p. 15 (in case of difficulty, it is recommended to work with the textbook).

It is important to pay attention to question 3 - discussion of hygiene rules for skin care. You can invite the children to develop a skin care guide.

Questions for the student who did the work (the beginning of the formation of a self-assessment algorithm):

-What did you need to do?

– Did you manage to complete the task?

– Did you do everything right or were there any mistakes?

– Did you compose everything yourself or with someone’s help?

– What was the level of the task?

– What skills were developed during this task?

– Now we are together with... (student's name) learned to evaluate their work.

Completing tasks from the workbook.

Possible answers to workbook assignments.

By doing tasks 1 Students must find an error in the captions to the picture: the designations of a blood vessel and a nerve, sweat and sebaceous glands are mixed up.

IN task 2 “reasonable advice” is given more often to wash hands to reduce the number of pathogenic microbes.

Task 3 also dedicated to hygiene. The guys independently write down “sensible advice”: “We must Rinse wound, lubricate the skin around it with iodine or brilliant green to kill germs, and bandage wounded place."

IN task 4 schoolchildren should mark the upper left and lower right pictures with a “+” sign (in the heat, the sweat glands bring excess water to the surface of the skin, it evaporates, and thereby the body cools).

By doing tasks 5 Students must underline the words baby cream, petrolatum.

Task 6* dedicated to tanning. You should get the following phrase: “Skin in the sun it's getting dark from tanning, which makes the skin less transparent. In winter, with a lack of sun, Tan disappears."

IN task 7 it is necessary to combine the image of Misha dressed in summer with the right picture with dilated blood vessels under the skin, the image of Misha in winter with the left picture. The text with correctly inserted words should look like this:

“When it’s hot, the skin turns red. Blood vessels located under the skin are expanding and fill with blood. Blood gives away excess heat, and the body cools down. In the cold, the opposite happens. The skin turns white because its blood vessels narrow. Blood doesn't give excess heat, and the body warms up».

V. Lesson summary.

– Exchange of opinions on the results of completing tasks.

– Why is skin called our natural clothing?

– Skin is a natural covering that protects our body from the effects of the external environment. Clothing does the same.

– What work were we doing now?

– What have you learned?

– Who dealt with it easily?

– Who has it been difficult so far?

– Who or what helped you cope?

– Who is happy with their work today?

– Who would like to fix anything? What? What do I need to do?

– What mark would you give yourself?

As real doctors, we should know about skin diseases and engage in preventative healthy lifestyle .

Skin hygiene.

We already know that sweat and oil are released through the pores onto the surface of the skin, and dust and dirt easily stick to them.

What happens to the skin? What should you do in such cases?

It is very important to wash the skin, because... Dirty skin harbors many microbes that can cause diseases of the skin and the entire human body. There are up to 40 thousand microbes per 1 cm of dirty skin.

How often should you wash your hands? How often should you wash your entire body?

Skin care rules.

(Read by a pre-prepared student):

At least once a week, wash your entire body with hot water and soap.

Wash your face every morning and evening.

Wash your hands after any contamination.

After washing, dry your skin.

Wisely temper your body with bathing, dousing, rubbing, and walking.

If the skin is dry or cracked, then lubricate it with cream or glycerin.

Lubricate scratches or small cuts with iodine or brilliant green.

If itching or ulcers appear, they should be shown to adults immediately and, if necessary, consult a doctor.

Skin diseases.

What skin diseases do you know? (to be supplemented by the teacher).

Let's all put together a reminder about first aid for some skin diseases.

Burns. Skin is so necessary for a person that if half of the entire surface of the body is severely burned, the person may die. Therefore, you understand the importance of handling fire carefully.

Rash. It can appear on the skin as a result of various diseases (allergies, chickenpox, measles, etc.).

Inflammation. Sometimes germs enter the body or scratch the skin. As a result, a pimple or abscess appears.

Sunburn. Tanning is a wonderful thing if you follow moderation and don’t try to get a black tan in one day.

Listen to what happened to Tanya from S. Marshak’s poem “How the girl Tanya sunbathed.”

Tanya forgot about lunch
Doesn't play with friends -
She doesn't care about her friends:
Lying down and sunbathing.

She dreams of getting a tan
So that the body becomes black -
Everyone will be looking at you
When you're tanned.

Some old man in swimming trunks
He shouted to her: “Hey, pigtail!
You're new to this,
Look, you’ll burn like a match!”

She doesn't want to follow an example
From those who give advice.
- Leave me alone, I’ll sunbathe!
Here are all her answers.

Even if I can’t bear to lie anymore,
But I won’t step out of the sand.
I won't leave here
And I won’t lie under the canopy!

Tanya was lying there, time passed.
There are fewer people.
The sun didn't burn so hot anymore
And Tanya was still lying there.

It's even hard to describe here
All the torment and suffering
When I had to save her
For everyone else's edification.

Now she can't wear a dress.
And judge for yourself
She has to sit all day
Don't lie there for hours.

A child passes by
And every now and then he whispers:
- And this girl yesterday
almost completely burned out!

What conclusion will you draw? Student response:

Excessive sun exposure can cause skin burns.

Providing first aid for burns and cuts.

In life, you often have to deal with various traumas. The most common are skin injuries (bruises, cuts). It is important to provide first aid correctly. Use the hygiene products provided to you when answering.

Why is it necessary to treat a wound with iodine?

What happens during severe frost?

Providing first aid for frostbite.

In case of frostbite, what help should be given?

2 1 2 3 1

1. Work in the textbook.

Questions on p. eleven.

2. Work in a workbook.

Workbook assignments to choose from.

Exercise 1 proposes to conditionally divide the organs of the human body known to schoolchildren into three groups. The organs that perform a variety of work include most of the organs of the musculoskeletal system, with the help of which we perform useful actions (walk, work with our hands). At the same time, we waste energy. The organs of the first group include, first of all, hands And legs. The expended energy allows the organs of the digestive system to be restored, i.e. stomach, intestines, liver etc. (restore the supply of nutrients), the respiratory system, i.e. lungs (restore optimal oxygen content), circulatory system, i.e. heart, vessels(they deliver to the cells all the substances they need and take away waste), the excretory system, i.e. kidneys (extract excess water and harmful substances from the blood). Finally, the organs that control the body include the nervous system, i.e. head And spinal cord, nerves.

These also include internal secretion organs, which schoolchildren may still know nothing about.

IN task 2 In the left column, the guys enter those organs that they can control. This hands And legs, and head, eyes, language, teeth and so on.

The teacher should keep in mind that we can also, to some extent, control the functioning of part of the organs of excretion (conscious removal of urine from the body) and digestion (excretion of feces by relaxing the sphincter of the rectum). The respiratory system stands somewhat apart. We can control the intercostal muscles and the diaphragm and increase the breathing rate, but breathing normally occurs without our participation, since it is controlled by the respiratory center located in the brain.

In the right column, the guys write down those organs that we cannot control. These are, first of all, the organs of the circulatory, respiratory, digestive and excretory systems: heart, vessels, stomach, liver, intestines, kidneys, lungs – most of the organs located inside the body.

IN task 3 students are asked to compare the two previous tasks (if they were completed by different groups of students, then the comparison is made at the summing up stage). Several conclusions can be drawn:

1) organs that restore spent forces, as a rule, act independently, regardless of our will;

2) bodies performing a variety of work, we, as a rule,

We can manage as we wish.

Questions for the student who did the work (the beginning of the formation of a self-assessment algorithm):

-What did you need to do?

– Did you manage to complete the task?

– Did you do everything right or were there any mistakes?

– Did you compose everything yourself or with someone’s help?

– What was the level of the task?

– What skills were developed during this task?

- Now we are together with... (student's name) learned to evaluate their work.

Carrying out verification work.

Possible answers to the tasks of test work No. 1.

Option 1 .

Required level. The brain belongs to the organs of the nervous system; eyes - to the senses; vessels - to the circulatory organs; spine - to the musculoskeletal organs.

Increased level. The hand contains the sensory organs, musculoskeletal and nervous systems, and circulatory organs.

Maximum level. The head contains the organs of digestion, breathing, senses, musculoskeletal and nervous systems, and circulatory organs.

Required level. Remove carbon dioxide - respiratory organs; digest food - digestive organs; cleanse the blood - excretory organs; continue the genus - reproductive organs.

Increased level. Growth, reproduction, respiration, mobility, inability to convert minerals into organic substances.

3. Increased level. The respiratory system will be affected by a cold; from drugs - nervous system; from too loud music - the senses.

Option 2 .

Required level. The lungs belong to the respiratory organs; stomach - to the digestive organs; kidneys - to the excretory organs; heart - to the circulatory organs.

Increased level. The leg contains the sensory organs, musculoskeletal and nervous systems, and circulatory organs.

Maximum level. The body contains the respiratory, excretory, reproductive, sensory, musculoskeletal and nervous systems, and circulatory organs.

Required level. Allows you to perceive the world around you - the senses; allow decision-making - organs of the nervous system; deliver nutrients to cells - circulatory organs; create support for the body - the musculoskeletal organs.

Increased level. Growth, reproduction, respiration.

3. Increased level. From overeating - the circulatory organs (the answer can be considered correct - the digestive organs); from smoking - respiratory organs; from falling from a tree – musculoskeletal system.