Presentation on inhalation and exhalation. Mechanism of inhalation and exhalation. Breathing regulation. Target. Based on knowledge about the structure of the organs of the respiratory system, understand the mechanism of respiratory movements - presentation. Checking homework

slide 1. Lesson topic:respiratory mechanism. Breathing regulation.
Developed by a biology teacher of the State Autonomous Educational Institution of the Republic of Tuva Tuva Republican Lyceum boarding school Svetlakova Irina Mikhailovna.


Slide 2. Good afternoon I am glad to welcome you to this lesson. I hope that our joint work will be useful and interesting. Let's smile at each other, straighten our shoulders, take a deep breath, tune in to positive emotions and productive activities.Epigraph "Who owns the breath controls his own destiny"
"Breath means life" Slide 3. Lesson Objectives : consider the mechanism of inhalation and exhalation, determine the role of humoral and nervous factors in the regulation of respiratory movements, protective reflexes, explain the dangers of smoking, give an idea of ​​the air environment and its protection.

Equipment. Presentationrespiratory mechanism. Breathing regulation. Flash animation, animations, videos, handouts.

educational: repeat the material on the structure and functions of the respiratory organs, on the significance of biological oxidation, consider the mechanism of inhalation and exhalation, determine the role of reflex and humoral mechanisms of respiration; explain the mechanism and significance of protective respiratory reflexes: coughing, sneezing,

to form new anatomical and physiological concepts in students - respiratory movements, vital capacity of the lungs; continue to develop in students the concepts of nervous and humoral regulation, continue to develop general biological concepts in students about the relationship between the structure and function of the respiratory system, self-regulation, continue to develop hygiene concepts (about the dangers of dust and smoking), develop students' skills to work with a textbook.

developing: For the development of creative thinking and speech of students, apply problem questions, solve calculation and logical problems, generalizing and other questions for reflection. continue the formation of students' intellectual skills, creative thinking and speech;

Educational : For the purpose of physical and hygienic education, to substantiate the rules of respiratory hygiene, the positive role of physical labor and physical education in the development of respiratory muscles, in health promotion, tactfully achieve an organized practical struggle of all students for their health, for clean air in the classroom, school and home.

Slide 5.

Lesson plan.

Updating knowledge on the topic "Respiratory system".

- differentiated work on cards (5-6 people).

- work with flash animation (1 person).

-Analyzing characteristics of the structure, functions, biological significance of the organs of the respiratory system. (4 people).

2. Learning a new topic.

3. Laboratory work

4. Fixing.

5. Grading.

Analysis of results.

General educational competencies:

- educational - organizational (organization of the workplace, the implementation of self-control and mutual control);
Educational - intellectual (the ability to analyze, synthesize, compare, generalize);
Educational and communicative (the ability to listen, ask clarifying questions).
To form the ability to independently acquire new knowledge and effectively apply them in practice;
Think critically and creatively, find rational ways to overcome difficulties, generate new ideas;
Properly work with information: be able to collect the necessary facts, analyze them, put forward hypotheses for solving the problem, establish patterns, formulate reasoned conclusions, find solutions;
Be sociable, contact in the group.
Informational (independently find, select, structure, store and transmit information);
Communicative (culture of verbal and non-verbal interaction);
Personal self-improvement.
general cultural
(experience in mastering the scientific picture of the world by students);
educational (coincidence of creative skills of productive activity, reflection, self-assessment, analysis, planning, goal-setting);

Slide 7.

Knowledge update.

First parties.

Complete tasks on cards.

.

Work at the blackboard flash animation. ANIMATION 1

1. Name and show bodies respiratory system.

2. Give a description of the organ of the respiratory system:

Structural features

Functions.

slide 8.

Respiratory system. (ANIMATION 1.)

The student works with flash animation (animation, with the correct display of the structures that make up the respiratory system, shows the correct name of the anatomical structure.

The student answers two questions:

1. What is breathing? What are the stages of this process?

2. How does voice formation occur and speech sounds are formed?

slide 9.

NOSE CAVITY.

slide 10.

LARYNX .

Why is it dangerous to talk while eating?

Slide 11.

TRACHEA AND BRONCH.

slide 12.

LUNGS.

Slides 13-16.

Card work.

Dear student, read all the tasks, select the tasks of your level. Please note that the time for completing tasks at each level is different.

Zero level, first level 5-8 min, second level 8-10 min, third level 10-12 min .

Card 1.

Exercise

Zero level. On "3"

Determine the order in which oxygen enters the cells of the body. Record this process with numbers.

1. From the lungs, oxygen enters the capillaries of the pulmonary vesicles.

2. Through the nasopharynx, trachea, bronchi, oxygen enters the lungs.

3. From the capillaries, oxygen, together with the blood, enters the pulmonary veins.

4. From the left ventricle, oxygenated blood enters the aorta.

5. From the pulmonary vein, oxygenated blood flows into the left atrium.

6. The aorta branches, a network of arteries and capillaries is formed, the capillaries supply the cells of the body with oxygen.

7. From the left atrium, blood enters the left ventricle.

First level on "4"

Set a match.

1. Hemoglobin. 2. Oxygen. 3. Carbon dioxide. 4. Diffusion.

5. Tissue cells. 6. intercellular fluid. 7. Pulmonary capillaries. 8. Capillaries in tissues. 9. Red blood cells. 10. Leukocytes.

1. What comes from the blood to the lungs?

II. What goes from the lungs into the blood?

Sh. What comes from the tissues into the blood?

IV . What comes from the blood to the tissues?

V pigment in the blood.

VI . Place of oxidation organic matter.

VII . consumers of oxygen.

VIII . physical phenomenon Cause gas exchange in the lungs.

IX . Cells are oxygen carriers. X. Decomposition product of organic substances.

Second level on "4"

breath?


outgoing gas exchange

they're called?

7. What physical process underlies Gas exchange?

8. How are bronchioles different from bronchi?

The third level on "5".

Explain the process or phenomena. Justify your answer

Climbers at high altitude begin to feel dizzy, weak, sometimes there is a loss of consciousness - "mountain sickness" occurs. These signs with frequent training eventually disappear. Guess what changes occur in this case in the human blood?

With a burnout, a person dies from suffocation, despite the fact that oxygen enters the lungs in sufficient quantities, and the admixture of oxygen oxide in the blood is only 0.1%. Why does suffocation occur?

Slide 17-20.

Card2.

Exercise

Dear student, after reading the tasks, select the tasks of your level. Please note that the time for completing tasks at each level is different.

Zero level, first level 5-8 min, second level 8-10 min, third level 10-12 min .

Zero level. On "3"

Fill in the missing words in the text.

“From the capillaries... of the circulation, oxygen enters the cells of the body. In arterial blood... more than in body cells. Oxygen by law... enters the cells. In cages
body it is involved in... organic matter. This generates... and releases energy. Carbon dioxide enters...
systemic circulation. Arterial blood in tissues
turns into..., which eventually returns to...
half a heart.

First level on "4"

Set a match.

Mucous membrane. 2. Pulmonary vesicles. 3. Lungs. 4. Bronchi. 5. Trachea. 6. Epiglottis. 7. Larynx. 8. Cartilaginous semi-
rings. 9. Pleura. 10. Nasal cavity.

1. Does not let food into the larynx.

II. Do not allow the trachea to narrow.

Sh. Purifies the inhaled air from dust and microbes and warms.

HA Superficial layer of the airways.

V . The initial part of the airway.

VI . Lines the outer surface of the lungs.

VII . Covers the wall of the chest cavity from the inside.

V Sh. The longest part of the airway.

IX . Place of gas exchange between lungs and blood.

X. Place of diffusion of gases.

Second level on "4"

Answer the following questions.

1. The lungs are located in the chest and are separated from its walls.

cavity. What is it called?

2. Inhalation is carried out due to the work of the diaphragm. It's breath

called abdominal. What makes breastfeeding

breath?

3. The cerebral cortex takes part in the regulation of breathing. How does it manifest itself?

4. What is the name of the part of the respiratory system in which there is no
outgoing gas exchange

5. There are receptors in the upper respiratory tract, which, when irritated, cause protective respiratory reflexes. How

they're called?

6. Since the respiratory muscles are presented transversely

striped muscles, a person can arbitrarily change the depth and frequency of breathing. What center regulates this process?

7. Due to what is the implementation of involuntary processes of inhalation and exhalation?

The third level on "5".

Explain the process or phenomena. Justify the answer.

1. Explain how the respiratory organs are anatomically related to the circulatory organs? How are the functions of the circulatory system related to the functions of the respiratory system.

2. How does respiratory failure affect the work of the heart, blood circulation? Give examples.

Slide 21.

Answers.

Card 1.

Level 0: 2,1,3,5,7,4,6.

1st level:

13; II. – 2; W - 3; IV. - 2; V - 1; VI. - 5; VII. - 5; VIII. - 4;

IX. - 9; X-3.

2nd level:

1 - pleural;

3rd level:

blood becomes capable of large quantities absorb oxygen than under normal conditions. In particular, athletes use this to improve their results.

Card 1.

0 level: large, oxygen, diffusion, exchange, carbon dioxide, veins, venous, right.

1st level:

16; II. - 8; W - 10; IV. - 1; V - 10; VI. - 9; VII. - 9; VIII. - 5; IX. – 2; X-2.

Level 2: 1 - pleural;

2 - due to an increase in the chest.

3 - in a delay, changes in the frequency and depth of breathing; 4 - dead space; 5 - cough, sneezing; 6 - respiratory center; 7 - due to the unconditioned reflex; 8 - diffusion; 9 - dimensions.

3rd level:

CO forms with blood Hb the compound carboHb, which is much stronger than oxyHb.

slide 22.

health moments.

Breathe with pleasure. Remember that a pleasant sensation in itself has a significant healing effect.
Positive emotions, respiratory joy - the key to success. Perform exercises only as long as it is pleasant for 1-2 minutes.
Focus on breathing exercise
enhances its performance.
Slow breathing is necessary to saturate the body with oxygen.

You need to breathe through your nose.
Wear comfortable clothing in a well-ventilated area or outdoors.

slide 23.

Breathing exercises.

1. Stand comfortably with your feet shoulder-width apart, feet parallel, resting on the middle of the foot.
2. Bend your arms at the elbows and at a level just above the chest, connect the hands with the bases of the palms and fingertips.

3. Imagine that a light is clamped between the palms that warms the hands, focus on it.
Smile, relax your face and hands. Lower your shoulders, keep your head and spine in line.
Breathing exercises.
1. Stand up straight, arms along the body, relaxed. Exhalation. We begin a slow breath As the lungs fill up, the shoulders rise,

and then exhale without delay, lowering the shoulders.

2. With inhalation, as the lungs are filled, the shoulders are slowly taken back, bringing the shoulder blades together and bringing the hands together behind the back. Then slowly exhale, moving the shoulders and arms forward, squeezing the chest. Do not strain your arms and shoulders.

3. Inhale as you lean to the left. With an exhalation, we take the starting position. Next, we lean to the right. We do not bend the neck and arms.

4. Alternately perform circular smooth movements with your shoulders. Same in reverse side Breathing is arbitrary. Completed.

slide 24.

TOPIC OF THE LESSON:
Mechanism of inhalation and exhalation. Breathing regulation.

Goals: to deepen and generalize knowledge on the respiratory system, to study the mechanisms of inhalation and exhalation, the regulation of respiratory processes.

Lesson plan .

1. Updating knowledge on the topic "Respiratory system". (mutual check).

2. Learning a new topic.

3. Laboratory work

4. Fixing.

5. Grading. Analysis of results.

slide 25.

Basic concepts.

Working with definitions. (definitions are written in a notebook - a dictionary).

inhale – initial phase respiration, during which air enters the lungs.

Exhalation - a separate expulsion of air from the lungs during breathing.

Air environment - a complex set of interrelated and interacting factors that have a constant impact on organism animal and human.

Involuntary regulation of breathing - a process carried out by the respiratory center, located in the medulla oblongata (one of the parts of the hindbrain). The ventral (lower) part of the respiratory center is responsible for stimulating inspiration; it is called the center of inhalation). Stimulation of this center increases the frequency and depth of inspiration.

The dorsal (upper) part and both lateral (lateral) ones inhibit inhalation and stimulate exhalation; they are collectively called the exhalation center (expiratory center).

respiratory center connected with the intercostal muscles by the intercostal nerves, and with the diaphragm by the phrenic nerves.

bronchial tree (a collection of bronchi and bronchioles) is innervated or controlled by the vagus nerve.

slide 26.

BREATHING MOVEMENTS - INHALE and EXHALE.

Breath means life. This phrase is undeniable. Usually, we associate breathing with inhalation and exhalation, that is, those respiratory movements that a person needs to ventilate the lungs.

Air enters the lungs because they can change their volume due to the elasticity of the alveoli, but there are no muscles in the lungs, but they still can expand and contract, due to what does this happen?

Problem question.

What is the secret of inhalation and exhalation? Why do muscleless lungs follow the movement of the chest?

Experience.

To answer the question, let's do an experiment. Try to inhale or exhale so that the diaphragm and pectoral muscles do not contract.

slide 27.

- Why is it not possible?

Now try holding your breath, blocking the exit from the airways and contracting the muscles in your abdomen and chest. What conclusion can be drawn from this experience?

Conclusion. For respiratory movements to be possible, it is necessary that the muscles can change the volume of the chest cavity and that the inhalation / exhalation of air through the airways must be free.

(ANIMATION RESPIRATORY SYSTEM 2 and 2.1.)

slide 28.

The lungs never contract or expand on their own, they simply passively follow the chest.The chest cavity expands due to the work of the respiratory muscles, which include the diaphragm and intercostal muscles.

The diaphragm is a muscular septum that separates the thoracic and abdominal cavities. When you inhale, it drops by 3-4 cm. At the same time, the volume of the chest increases by 1000-1200 ml. In addition, the intercostal muscles contract, which raise the lungs, which also increases the volume of the chest cavity, while the lungs expand. In the distended lungs, the pressure becomes lower atmospheric pressure and as a result of the pressure difference, outside air enters the Airways. There is a breath. After inhalation comes exhalation and the diaphragm, and the intercostal muscles relax, the ribs descend, the volume of the chest decreases, the lungs contract and push the air out through the airways, exhalation occurs.

slide 29.

Basic concepts.

Tidal volume- the volume of air inhaled during a normal inhalation and exhaled during a normal exhalation.

VITAL CAPACITY is the expiratory volume after the previous maximum inspiration.

ISP RESERVE VOLUME - the amount of air that a person can supplement to inhale after a quiet breath.

RESERVE EXHAUST VOLUME - the amount of air that a person can add to inhale after a quiet exhalation.

Slide 30. ( Additional Information, will be enabled if there is enough time)

VITAL CAPACITY OF THE LUNGS.

Is VC equal to lung volume?

It turns out not. This is due to the fact that the lungs always have a residual volume of air equal to approximately 1 liter.

VC = tidal volume + inspiratory reserve volume + expiratory reserve volume.

VC depends on the age, gender and degree of training of a person.

VC is measured with a special device - a spirometer.

Sport and physical activity contribute to the development of muscles that take part in respiratory movements, which means that the Vital Capacity of the Lungs increases. (WISH).

slide 31.

Guys, what do you think regulates the breathing process?

slide 32.

From first to last day man breathes rhythmically throughout his life. The rhythm of his breathing never goes astray (is not disturbed), only its frequency does not change.

A newborn baby takes about 60 breaths per minute, 5 summer child- 25, at the age of 16 - 18, movements become 16 -18 per minute. In old age, breathing becomes a little faster again.

WHAT IS THE RHYTHM OF BREATHING DEFINED? AND ON WHAT DOES IT DEPEND ON?

The respiratory center is located in the medulla oblongata. Approximately every 4 seconds in the respiratory muscles there are respiratory impulses that cause the chest to rise and the diaphragm to lower.

THANKS TO THIS, THE INSPIRATION HAPPENS.

Expiration at rest is passive. The ribs are lowered by gravity. When inhaling, the muscles stretch, mechanical receptors located in the walls of the lungs are excited, impulses are transmitted to the respiratory center of the medulla oblongata and inhibit its activity. The respiratory muscles relax and exhalation occurs. The work of the respiratory center affects the higher respiratory centers located in the cerebral cortex. Thanks to their activity, respiratory movements change.

In this way, you can consciously change the frequency of breathing.

slide 33.

REGULATION OF BREATHING.

Intensity appears:

1. when playing sports.

2. in emotional states.

Influence of respiratory centers of protective reflexes, physical activity, emotions -----)

1. respiratory stimulation -------) higher respiratory centers

2. Deceleration of breathing -------) higher respiratory centers, protective reflexes, emotions.

(ANIMATION 5, 6 7).

slide 34.

REGULATION OF BREATHING.

Talk about nervous regulation will not be finished if we do not talk about such respiratory mechanisms - sneezing and coughing.

1. Irritation of the mucous membrane. (nasal cavity ---- Sneezing) (larynx, trachea, bronchi, cough)

Dust;

Bad smelling substances.

2. The desire of the body to throw out, get rid of the irritating factor.

3. receipt of an impulse in the medulla oblongata.

4. The medulla oblongata sends signals to the muscles

5. as a result of breathing vocal cords close, and a stream of air under pressure breaks out.

(ANIMATIONS 8 and 9)

Irritation of the nasal mucosa - Sneezing.

Irritation of the mucous membrane of the larynx, trachea, bronchi) - cough.

slide 35.

FIXING.

Laboratory work No. 8.1.
Functional breath tests with maximum breath holding before and after

10 squats (three-phase test by Professor L.G. Serkin)
Target: establish the effect of holding the breath on the respiratory rate.
Equipment: stopwatch (watch with a second hand).
PROGRESS
1. Determine the time to hold your breath while inhaling in a sitting position. The subject breathes calmly for 1 min in a sitting position, and then, on command, after a normal exhalation, takes a deep breath and holds his breath as long as he can, while holding his nose. The experimenter, using a stopwatch, determines the time from the moment of holding the breath to the moment of its resumption. The result is fixed.
2. Do 20 squats in 30 seconds and again determine the breath holding time on inspiration.
3. Rest exactly 1 minute and repeat step 1.

Evaluation of results

Messages:1. "The effect of nicotine on the respiratory system".

"Air environment and its protection"

slide 36.

VERIFICATION WORK.

“Mechanism of inhalation and exhalation

Programmed Poll

Gas exchange takes place _______.

The bronchi branch and end in _______

Alveolar and exhaled air has _______.

The intercostal muscles and the diaphragm are classified as _______.

Air passing through the nasal cavity _______.

After acceptance a large number food breath _______ .

The respiratory center is in a state of constant _______.

Each lung is covered with _______ on top.

When you inhale, is the air pressure greater or less than atmospheric pressure? __________________

The lung follows the movement of the chest, as the pressure in the pleural space is _______.

slide 37.

Answers

Gas exchange is carried out by _______ (diffusion).

The bronchi branch and end in _______ (pulmonary vesicles).

Alveolar and exhaled air has _______ (the same gas composition).

The intercostal muscles and the diaphragm are classified as _______ (respiratory muscles).

Air, passing through the nasal cavity, _______ (cleaned, warmed, disinfected).

After eating a large amount of food, breathing _______ (difficulty).

The respiratory center is in a state of constant _______ (activity).

Each lung is covered with _______ (pleura) on top.

When you inhale, is the air pressure greater or less than atmospheric pressure? (less).

The lung follows the movement of the chest, as the pressure in the pleural space is _______ (negative).

slide 38.

Answers: 1.D, 2.B, 3.D, 4.B, 5.C.

Slide 39-40.

0 level.1.§28 according to the textbook by D.V. Kolesov, R.D. Mash, compose a syncwine on the topic “Sources of atmospheric air pollution”.

Answer the questions in writing §.

2. Creative Lab:

1 LEVEL .
1. When is nasal breathing difficult? What are the consequences of this violation? Suggest a code of practice for respiratory hygiene.
2. Develop recommendations and a set of exercises to correct breathing.

2 LEVEL ,

3. Why is it necessary to conduct wet cleaning daily?

Suggest the easiest way to maintain high

4. working capacity and mental abilities of students during the school day.

3 LEVEL.

1. How much air passes through the lungs of a person with calm breathing per minute, per hour, per day, if the tidal volume of air is 500 ml. And the respiratory rate is 18 times per minute?

2. Knowing that the inhaled air contains about 20% oxygen, determine how much oxygen a person passes through the lungs per day with calm breathing.

3. Knowing that the exhaled air contains 4% carbon dioxide, determine how much carbon dioxide a student emits per minute, in 1 hour, how much all students in the class do in 1 hour.

Slide 41.

Additional Information.

Inspiratory and expiratory mechanism on the Donders model.

The intake of air into the lungs and its removal (expulsion) can be observed on the model of the inventor and physiologist Donders

For work we need:

equipment. glass funnel, 2 balloons, thread, adhesive tape.

Progress:

1.ball we put it inside the funnel, and pull its valve outward and pull it from the outside and tightly tie it with a thread.

2. second the ball in half and pull it over the wide socket of the funnel so that a rubber bottom is formed. And in order to keep the bottom better, we fasten it with adhesive tape on the outside of the funnel.

the tube of the funnel simulates the upper respiratory tract, the ball inside the funnel is a lung, the rubber bottom is the diaphragm. The glass body of the funnel is the walls of the chest cavity. When the rubber bottom is retracted, the pressure in the model and the chest cavity drops and the outside air enters the ball, it swells like a lung during inhalation, when we release the diaphragm model, the air comes out of the ball - exhalation occurs

It should be noted that not only the lungs, but also the skin takes part in human breathing (the skin on the chest, abdomen, and back breathes especially intensively.

Slide 42.

A lesson for 8th grade students studying according to the textbook "Biology. Human", authors Dragomilov A.G. and Mash R.D. The lesson is studied in the topic "Breathing", the following questions are considered: the mechanism of breathing, the regulation of breathing, mini practical work, independent work with paragraph material.

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Preview:

Subject. Breath. Lesson topic. Breathing mechanism.

Goals.

Educational:

1. Organization of students' activities in the perception, comprehension and memorization of the process of the respiratory mechanism, the concept of "lung capacity".
2. Repeat, consolidate, expand students' knowledge on this topic.

Educational:

1. Education of culture in communication with comrades, the ability to listen and hear others.
2. Cultivate a positive attitude towards your health.

Educational

1. Developing students' curiosity cognitive interest to the subject.
2. Formation of concepts about the unity of the processes of inhalation and exhalation.
3. Development of creative and logical thinking and speech of students in solving problematic issues, the development of memory.

Tasks . Find out how the breathing mechanism is carried out, what is the vital capacity of the lungs and the importance of proper breathing for health.

Lesson type: Combined.

Teaching methods:

1. Problem-search method (solving problematic issues, discussing the results of experiments).
2. Demonstration method of working with a multimedia manual.
3. Method of working with didactic material.
4. The verbal method is the teacher's story.

During the classes

1. Organizational moment

2. Creating a problem situation

3. Setting goals and objectives of the lesson

4. Learning new material

5. Lesson conclusions

6. Fixing

7. Summing up the lesson

1 row works with tests. Tests are pre-set on desks.

organizational moment. 1 minute

Hello guys. Please, have a seat. My name is Natalya Ivanovna. Today we are working together and I look forward to your support and cooperation.

Let's review what you have already learned on the topic "Breathing".

Do you want to test yourself?

You need to choose the correct answer.(Slide Check homework).

Updating of basic knowledge.

8 minutes

1. Finish the thought.

1. Controls the entrance to the larynx - epiglottis
2. Passes along the trachea - esophagus
3. The function of cilia in the nasal cavity - cleansing
4. Structural units of the lungs - alveoli
5. Barrier that separates the chest cavity from the abdominal - diaphragm

2. The game "Yes - No." Do you agree with my statement?

1. Gas exchange between air and blood takes place in the lungs
2. The pleural fluid provides gas exchange
3. Blood from the heart to the lungs is oxygenated
4. Maintaining the constancy of the gas composition in the alveoli is carried out due to respiratory movements.
5. The initial part of the airway is the oral cavity.
6. Cartilaginous half rings do not allow the trachea to narrow.
7. Erythrocytes are oxygen carrier cells.
8. The pleural cavity is the space between the pleurae.
9. The epiglottis covers the entrance to the esophagus.

10. Lungs are formed by muscle tissue.

1. “Without a nose, a man - the devil knows what - a bird is not a bird, a citizen is not a citizen - just take it and throw it out the window! .. N.V. Gogol. "Nose".

But seriously? Why does a person need a nose?

4 . There is a 3 liter jar on the table. It says "Dust" on it.

Tell me, please, what is the connection between the structure of the trachea and a dust can?

Guys, hand over your cards, please.

Learning new material. 25 minutes

Problematic situation.

Teacher.

Students argue among themselves and express several opinions on how air enters the lungs:

1. Atmospheric air enters the lungs "by gravity", greatly inflates the lungs and chest.
2. Air enters because the lungs in the chest expand and suck in air.
3. A person consciously, at will, inhales and exhales.

Who is right?

Gas exchange is possible only under the condition of a constant change of air. Do you know why a newborn baby is slapped on the ass as soon as he is born?

He screams in pain and takes his first breath, the lungs expand and the person begins to breathe.

TEACHER . In the lesson we should find out:

1. what underlies the mechanism of respiration,

2.how does the mechanism of respiration occur

3. The importance of proper breathing to improve human health.

Write down the topic of the lesson. (Slide. LESSON TOPIC)

Homework.Page 142-145, answer questions on pages 146-147.

Teacher.

Inhalation and exhalation rhythmically follow one after the other. Air enters the lungs, the lungs can change their volume due to the high elasticity of the alveoli.

You probably remember that there are 300-350 million alveoli in the lungs with a total area of ​​150 sq.m..

But the lungs do not have muscles that could alternately compress and expand them.

Why do lungs have the ability to change their volume?

Experiment.

Put your palms on your ribs, breathe. How does the volume of the chest change?

What causes the chest to grow or shrink?

Teacher.

Breathing movements are carried out with the help of special muscles. Which ones? (Contraction and relaxation of the intercostal muscles and diaphragm).

The lungs never expand on their own. They passively follow the chest.

Why do the lungs passively follow the chest?

Do you remember what a pleural slit is?

Teacher.

As you remember, it is hermetically sealed and the pressure in the pleural space is below atmospheric pressure. Due to the difference in pressure, the lungs move behind the chest, and inspiration occurs.

Inhalation is followed by exhalation.

Let's look at the mechanism of inhalation and exhalation.(

Why does inhalation and exhalation alternate?

What muscles are involved in the mechanism of inhalation and exhalation?

Advance. The contraction of the respiratory muscles is due to the impulse coming from the DC every 4 seconds.

Slide Mechanism of respiration.

Let's summarize:

Inspiratory mechanism

Contraction of respiratory muscles (intercostal and diaphragmatic)

Enlargement of the chest cavity

Decreased pressure in the chest cavity

Sucking air into the lungs

The scheme is written in a notebook.

Teacher.

Getting air into the lungs and pushing air out of the lungs is a physical process. This can be proved using the Donders model.(Disk Biology. Man 8th grade. Series "1C: School").

(We can make this model and experience test at home).

How many breaths does a person take per minute?

Can we breathe properly?

Experiment.

Put your palms on your chest, count the number of breaths per minute. I mark the time. Write down the result in a notebook.

The rate of respiratory movements per minute in adolescents is 12-18 per minute, in adults - 16-20.

Teacher.

It turns out that proper breathing is very important, especially in winter and during the transitional winter-spring period, during a flu epidemic. According to experts, improper breathing significantly increases the likelihood of respiratory infections entering the body, which increases the risk of flu or colds.

Many people breathe too fastand shallow, from time to time holding inhalation and exhalation. This type of breathing is called shallow breathing..

As a result, the lungs do not have time to properly ventilate - fresh air enters only the outer sections, while most of the lung volume is not renewed. And that's all that viruses and bacteria need.(Disk Biology. Man Grade 8. Series "1C: School").

Conclusion. You need to breathe deeply and measuredly

Teacher.

If you do less14 breaths per minute - wonderful. You can rightfully be proud of yourself. Taking in the air with a full chest, you let the lungs straighten out, perfectly ventilate them, that is, make your respiratory system almost invulnerable to infectious agents.

A good result is considered from14 to 18 breaths per minute. This is how most practically healthy people breathe, who can get the flu or SARS no more than 2 times a season.

More than 18 breaths per minute is already a serious cause for concern.. With shallow and frequent breathing, only half of the inhaled air enters the lungs. This is clearly not enough to constantly update the pulmonary atmosphere..

Practical part.

We live in conditions that adversely affect the respiratory system and cause its diseases. But this problem has its own solution -breathing exercises,which not only trains, but also strengthens it. And I would very much like to introduce you to some breathing exercises.

1. Alternate breathing with both nostrils.
2. Breathing while walking: inhale - 1 step, exhale 2 steps.

One of the important indicators of the state of the respiratory system isvital capacity of the lungs.

Let's find out for ourselves what it is.

Book work. Read the article "Vital Capacity" on pages 143-144.

Text work.

1. What is the vital capacity of the lungs?(the largest volume of air a person can exhale after taking the deepest breath possible)

2. What is the vital capacity of an adult?

3. How does the vital capacity change in people of different professions?

4. What instrument measures vital capacity.

5. Does smoking affect the vital capacity of the lungs.

Generalization.

Let's remember the beginning of the lesson. What questions did we ask

(Slide topic of the lesson.

Slide Conclusions).

1. Air enters the lungs through respiratory movements, which involve the intercostal muscles and the diaphragm.
2. Breathing movements occur rhythmically.
3. You need to breathe deeply and measuredly.

Consolidation. Working with tests

Grading the work in class

Since you did a very good job today, I think everyone will get good grades.

I am very satisfied with you! Well done boys! Thank you!

Breathing movements

Breathing movements

ZELZHEL Residual volume Deep exhalation Deep inhalation Reserve inspiratory volume Reserve expiratory volume Inhaled volume Ventilation of the lungs - The amount of air that enters during a quiet breath and goes out during a quiet exhalation is called TIDAL VOLUME. (500 cm3) the amount of air passing through the lungs for 1 minute (7 liters per minute) After a quiet breath, a person can inhale about 1500 ml of air. This is the so-called inspiratory reserve volume. After a calm exhalation, a person can exhale about 1500 ml of air. This is the so-called expiratory reserve volume. Inspiratory reserve volume + tidal volume + expiratory reserve volume = VC (vital capacity) Spirometer - a device for determining VC

The mechanism of inhalation and exhalation Lungs are passive Follow the chest Due to the difference in pressure between the lungs and the pleural cavity the cell descends 3. The diaphragm rises 4. The volume of the chest decreases 5. The pressure in the alveoli becomes higher than atmospheric pressure 6. The air goes into the o / s Lungs The pleural cavity Inhale air Р low

Nervous and humoral regulation of breathing inhalation - excitation of alveolar receptors - vagus nerve - exhalation center (excitation) - spinal cord- intercostal muscles and diaphragm - chest volume decreases - exhalation Increase in CO 2 concentration, Excites the respiratory center and causes increased contraction of the respiratory muscles and increased respiration.