The size of the heart is 0.47% of the total body weight, approximately equal to the size of a human fist.

The heart is located in the middle between the right and left lungs, shifted to the left side.

The apex of the heart is directed downward, forward and slightly to the left.

Heart beats are most felt to the left of the sternum.

Solve the problem:

Calculate the mass of your heart if your body weight is 40 kg.

A heart - hollow muscular sac.

Structure walls hearts

Outer layer Middle layer Inner layer

(connective tissue) (muscle tissue) (epithelial tissue)

myocardium

peculiarities

striated special muscle fibers

muscle fibers

able self-excite,

those. impulses arise in themselves

The ability of an organ to work without signal stimuli from the outside is called automatism.

Cardiac muscle has this ability, i.e. . automatism, thereby maintaining the sequence of the cardiac cycle.

Pericardium inner wall

highlights liquid

connective tissue bag

reduces friction

Regulation of heart contractions.
(strength and heart rate)

nervous

parasympathetic nerve (wandering)

slows down the heart

sympathetic nerve

speeds up the work of the heart

humoral

Adrenaline ----- speeds up the work

Potassium ion --- slows down the work of the heart

Calcium ion --- speeds up the work of the heart

The structure of the heart and the vessels associated with the heart.

It is divided by a solid partition into two parts - left and right.

Atrial walls much thinner than the walls of the ventricles, which is due to the fact that the work done by the atria is relatively small.

When they contract, blood enters the ventricles. The ventricles do much more work, pushing blood along the entire length of the vessels .

Mthe muscular wall of the left ventricle is thicker than the wall of the right, because it does a great job - it pushes blood through big circle blood circulation

conclusions: 1. The structure of the heart corresponds to its function.

2. The muscles of the heart have automatism, due to which the sequence of the cardiac cycle is preserved.

3.Nervous and humoral regulation of the heart adapts its work to the needs of the body

Download:

Slides captions:

Topic
The structure and work of the heart
The position of the heart in chest. Features of the heart muscle. Regulation of heart contractions.
The size of the heart is 0.47% of the total body weight, approximately equal to the size of a human fist. The heart is located in the middle between the right and left lungs, shifted to the left side. The apex of the heart is directed downward, forward and slightly to the left. Heart beats are most felt to the left of the sternum.
Solve the problem: Calculate the mass of your heart if your body weight is 40 kg.
The heart is a hollow muscular sac. Structure of the heart wall Outer layer Middle layer Inner layer (connective tissue) (muscle tissue) (epithelial tissue) myocardium impulses arise in themselves
The ability of an organ to work without signal stimulation from outside is called automatism.
The heart muscle has this ability, i.e. automatism, thanks to which the sequence of the cardiac cycle is preserved.
Pericardial sac inner wall releases fluid connective tissue "bag" reduces friction
Regulation of heart contractions. (strength and frequency of heart contractions)
nervous
humoral
Parasympathetic nerve (vagus) slows down the heart Sympathetic nerve speeds up the heart
Adrenaline----- speeds up the work of potassium ion--- slows down the work of the heart Calcium ion--- speeds up the work of the heart

The structure of the heart and the vessels associated with the heart.
The structure of the heart corresponds to its function. It is divided by a solid partition into two parts - left and right.
Each part of the heart is divided into two sections that communicate with each other: the upper one is the atrium and the lower one is the ventricle.
The walls of the atria are much thinner than the walls of the ventricles, which is due to the fact that the work done by the atria is relatively small. When they contract, blood enters the ventricles. The ventricles do much more work, pushing blood along the entire length of the vessels. The muscular wall of the left ventricle is thicker than the wall of the right one, because it does a lot of work - it pushes blood through the systemic circulation
From the left ventricle, blood enters the aorta (the largest artery), from the right ventricle - into pulmonary artery.
Aorta
Pulmonary artery with semilunar valve
Right ventricle
Flap valves with tendon filaments and papillary muscles
inferior vena cava
Right atrium
superior vena cava
There are semilunar valves between the ventricles and arteries, which prevent blood from returning from the arteries to the ventricles. Therefore, blood only moves in one direction.
Checking the execution of tasks
1. Right ventricle 2. Right atrium 3. Left ventricle 4. Left atrium 5. Valves 6. Semilunar valves 7. Aorta 8. Pulmonary artery 9. Superior vena cava 10. Pulmonary vein 11. Tendinous filaments 12. Papillary muscle 13. inferior vena cava
Conclusions:
1. The structure of the heart corresponds to its function. 2. The muscles of the heart have automatism, due to which the sequence of the cardiac cycle is preserved. 3. Nervous and humoral regulation of the heart adapts its work to the needs of the body.

Preview:

Route sheet (work plan for the lesson).

1. The position of the heart in the chest. Features of the heart muscle. Regulation of heart contractions.

Using a multiprojector, work according to the schemes "Structure of the wall of the heart", "Regulation of heart contractions".

Complete the task: 1) Fill in the table

Tasks

Answers

1. What tissues form the walls of the heart?

2) Solve the problem:

2. The structure of the heart and the vessels associated with the heart. 1 group(When completing task 2

Do tasks 3, 4)

1 - 1 -

2 - 2 -

6 –

10 -

11 -

12 -

2 - 13 -

3. Cardiac cycle.

3. Cardiac cycle. 2 group

Read textbook, p. 112, 113 "Cardiac cycle", use Figure 54, p. 112.

Complete the task:

Preview:

Lesson 19

Topic: The structure and work of the heart

Tasks: to find out the structural features of the heart in connection with the functions performed, the regulation of the activity of the heart, the rhythm of contraction and relaxation of the heart (cardiac cycle), the position of the heart in the chest cavity.

Equipment: multi-projector, computers, tables

During the classes

Learning new material

1. The position of the heart in the chest. Regulation of heart contractions.

(teacher's story, use of a multiprojector, work according to the schemes "Structure of the wall of the heart", "Regulation of heart contractions", drawing "Location of the heart in the chest cavity")

(work with electronic text, work with the picture "Structure of the heart and vessels associated with the heart" - designate the picture)

3. Cardiac cycle

(working with the text of the textbook p. 112, 113, completing task 91 in the workbook).

4. Checking the execution of tasks.

Fixing:

1. Human heart:

A) 3-chamber, b) 2-chamber, c) 4-chamber

2. Significance of heart valves:

A) a protective function, b) provide nutrition to the heart, c) ensure the movement of blood in one direction

3. The heart has automatism - this means:

A) contract and relax with participation nervous system,

B) is able to contract without the participation of the nervous system,

C) adapts to changing conditions of the internal environment

4. What muscles form the heart:

A) striated, b) smooth,

5. Which vessel leaves the left ventricle:

A) aorta, b) inferior vena cava, c) superior vena cava

6. Vagus nerve

A) slows down the work of the heart, b) speeds up the work of the heart, c) does not affect the work of the heart

7. The pericardial sac is formed:

BUT) epithelial tissue, b) connective tissue, c) muscle tissue

8. The sequence of phases of the cardiac cycle is:

A) atrial contraction --- reduction ventricles --- pause,

B) ventricular contraction --- atrial contraction --- pause,

C) atrial contraction --- pause --- ventricular contraction

Key to the test: 1c, 2c, 3b, 4a, 5a, 6a, 7b, 8a.

Homework: § 22, workbook ass. 89

1. Position of the heart in the chest. Features of the heart muscle.

Regulation of heart contractions.

(working with a multi-projector)

Solve the problem:

A heart - hollow muscular sac.

The structure of the wall of the heart

Outer layer Middle layer Inner layer

(connective tissue) (muscle tissue) (epithelial tissue)

Myocardium

peculiarities

striatedmuscle fibersspecial muscle fibers

Able self-excite

Those. impulses arise

In themselves

The ability of an organ to work without signal stimuli from the outside is called automatism.

The heart muscle hasthis ability, i.e.. automatism , thereby maintaining the sequence of the cardiac cycle.

Pericardiuminner wall secretes liquid

Connective tissue "bag" reduces friction

Regulation of heart contractions.

Nervous Humoral

parasympathetic nerve(wandering) Adrenaline ----- speeds up the work

slows down the heart

potassium ion --- slow down

Sympathetic nerve Calcium ion--- speeds up work

speeds up the work of the heart

2. The structure of the heart and vessels associated with the heart (Group 1)

Work with electronic text. Working with the drawing "The structure of the heart and the vessels associated with the heart" - designate the drawing

Atrial walls much thinner than the walls of the ventricles, which is due to the fact that the work done by the atria is relatively small. When they contract, blood enters the ventricles. The ventricles perform significantly more work, pushing blood along the entire length of the vessels.

The muscular wall of the left ventricle is thicker than the wall of the right, because it does a great job - it pushes blood through the systemic circulation.

between each atrium and ventriclethere are valves in the form of flaps -flap valves. Tendon threads attached to papillary musclesthat connect the valves to the floor of the ventriclesand do not allow them (valve valves) to turn outtowards the auricles. During atrial contraction, the valve leaflets hang down into the ventricles, allowing blood to flow freely into the ventricles. When the ventricles contract, the valve flaps close and blood cannot enter the atria.

Blood flows from the left ventricle into the aorta (the largest artery), from the right ventricle -into the pulmonary artery.

Between ventricles and arteries there are semilunar valveswhich prevent the return of blood from the arteries to the ventricles. Therefore, blood only moves in one direction.

3. Cardiac cycle

Work with the text of the textbook.112, 113. Complete task 91 in the workbook.

4. Checking the execution of tasks.

Solve the problem: Calculate the mass of your heart if your body weight is 40 kg.

(40kg : 100 0.47 = 0.188kg (188g))

1. Right ventricle

2. Right atrium

3. Left ventricle

4. Left atrium

5. Leaf valves

6. Semilunar valves

7. Aorta

8. Pulmonary artery

9. Superior vena cava

10. Pulmonary vein

11. Papillary muscle

12. Tendon threads

13. Inferior vena cava

Cardiac cycle

Output:

1. The structure of the heart corresponds to its function.

2. The muscles of the heart have automatism, due to which the sequence of the cardiac cycle is preserved.

3. Nervous and humoral regulation of the heart adapts its work to the needs of the body.

Additional Information

* The heart makes 100 thousand per day. strokes, almost 40 million strokes per year.

* The mass of the heart is 1/200 of the body mass, but 1/20 of all energy resources organism.

* The heart beats 25 billion times in a person's life. This work is enough to lift a train up Mont Blanc.

2) Solve the problem:

Calculate the mass of your heart if your body weight is 40 kg

2. The structure of the heart and the vessels associated with the heart.

1 group (When completing task 2, complete tasks 3, 4)

Work with electronic text. Working with drawings "The structure of the heart and the vessels associated with the heart"

Complete the task: 1) Label the picture.

1 - 1 -

2 - 2 -

6 –

10 -

11 -

12 -

2 - 13 -

3. Cardiac cycle.

3. Cardiac cycle. 2 group(When completing task 3, complete tasks 2, 4)

Read textbook, p. 112, 113 "Cardiac cycle", use Figure 54, p. 112.

Complete the task:

1) Complete task 91 in the workbook.

4. Work with tests (after completing tasks 1, 2, 3)

1. Human heart: a) 3-chambered, b) 2-chambered, c) 4-chambered.

2. What is the importance of heart valves? a) a protective function, b) provide nutrition to the heart, c) ensure the movement of blood in one direction.

3. The heart has automatism. This means: a) it contracts and relaxes with the participation of the nervous system, b) it is able to contract without signal stimulation from the outside,

C) adapt to changing environmental conditions.

4. Which vessel leaves the left ventricle: a) aorta, b) inferior vena cava, c) superior vena cava.

5. The vagus nerve: a) slows down the work of the heart, b) speeds up the work of the heart, c) does not affect the work of the heart.

6. Indicate the correct sequence of phases of the cardiac cycle - these are:

a) atrial contraction - ventricular contraction - pause, b) ventricular contraction - atrial contraction - pause, c) atrial contraction - pause - ventricular contraction.

7. The pericardial sac is formed by: a) epithelial tissue, b) connective tissue, c) muscle tissue.

8. Myocardium is: a) the outer layer of the heart wall, b) the middle layer of the heart wall, c) the inner layer of the heart wall.

5. Checking the execution of tasks.

The structure of the heart corresponds to its function.

It is divided by a solid partition into two parts - left and right.

Each part of the heart is divided into two sections that communicate with each other: the upper- atrium and lower - ventricle.

The size of the heart is 0.47% of the mass of the entire body, approximately equal to the size of his fist.

The heart is located in the middle between the right and left lungs.

Slightly shifted to the left.

The apex of the heart is directed downward, forward and slightly to the left.

Heart beats are most felt to the left of the sternum.

1 slide

What is a heart? ... Maybe between the ribs and the aorta Beats a ball, similar to the globe of the earth? One way or another, everything earthly Fits within its limits, Because there is no rest for it, Everything matters… E. Mezhelaitis “Heart” The heart has been continuously working all our life. What is the secret of his tirelessness?

2 slide

Normally, excitation periodically occurs in the sinoatrial node and spreads to the atria, and then to the ventricles. Sinus node - pacemaker of the heart Excitation occurs Conducting system Excitation is conducted Contractile muscles of the heart Contraction occurs

3 slide

The contractions of the chambers of the heart increase the pressure of the blood in them. The difference in blood pressure between the chambers of the heart and the vessels departing from it creates the driving force of blood circulation. Contraction (systole) and relaxation (diastole) of the chambers of the heart occur in strict order, forming a cardiac cycle. The cardiac cycle is an alternation of contractions (0.4 sec) and relaxation (0.4 sec) of the heart.

4 slide

I phase II phase III phase pause CARDIAC CYCLE 0.3 0.4 0.4 50% work 50% rest 1. How long do the atria rest? 0.7s. 2. How long do the ventricles rest? 0.5s. 3. How long do the atria and ventricles rest together? 0.4s.

5 slide

1. Atrial contraction. The ventricles are relaxed, the cusp valves are open, the semilunar valves are closed. 2. Contraction of the ventricles. The atria are relaxed, the flap valves are closed. 3. Complete relaxation of the heart.

6 slide

7 slide

What is the secret of tirelessness and working capacity of the heart? The heart works only at the moment when it pushes out blood, and rests the rest of the time.

8 slide

In children and adults, the heart contracts at different rates: in children up to a year, 100-200 beats per minute, at 10 years old - 90 beats per minute, at 20 years and older - 60-70 beats per minute; after 60 years, the number of contractions increases and reaches 90-95 contractions per minute. With physical and emotional stress, the heart pumps, on average, 3-5 times more blood per minute than at rest. The heart makes 100 thousand beats per day. Almost 40 million strokes per year.

9 slide

In the myocardium there are special muscle cells that form the conduction system of the heart. These cells have automaticity - the ability to spontaneously excite, that is, to generate electrical impulses.

10 slide

The impulses are recorded using an electrocardiograph and recorded as an electrocardiogram (ECG). An ECG is recorded using a special device - an electrocardiograph. ECG can be used to diagnose various diseases hearts.

11 slide

Electrocardiogram (ECG) Reflects electrical phenomena in the beating heart. P- reflects the electrical activity of the atria QRS- reflects the electrical conduction of the ventricles T- reflects the electrical activity of the ventricles The heart is great!

12 slide

Humoral Sympathetic NERVOUS Parasympathetic Adrenaline Ca²+ ions Acetylcholine K+ ions

13 slide

Imagine the rhythmic work of the heart of a 52-year-old person, and, based on the duration of the phases of the cardiac cycle, determine how many out of 52 years he: a) rested the muscles of the ventricles of the heart; b) the muscles of the atria were resting; c) flap valves worked (were closed); d) the semilunar valves worked (were closed). Solve biological problems a) 52 y. - 0.8 s x y. - 0.5 s 52 x 0.5 X = 0.8 X = 32.5 years b - d solve independently Answer: the muscles of the ventricles of the heart rested 32, 5 years

14 slide

We check b) 52 g. - 0.8 s x y. - 0.7 s 52 x 0.7 X \u003d 0.8 X \u003d 45.5 years Answer: the atrial muscles rested for 45.5 years. c) 52 g. - 0.8 s x y. - 0.3 s 52 x 0.3 X = 0.8 X = 19.5 years Answer: the flap valves worked (were closed) for 19.5 years. d) 52 years - 0.8 s x y. - 0.5 s 52 x 0.3 X = 0.8 X = 32.5 years Answer: the semilunar valves worked (were closed) for 32.5 years.

summary of presentations

human heart

Slides: 9 Words: 318 Sounds: 0 Effects: 0

The heart was and remains an organ that indicates the whole state of a person. Educational questions: What is the structure of the heart? What are the phases of the heart? What is a cardiac cycle? What happens to the heart during various physical activity? Didactic goals of the project: Methodological tasks: Is life possible with an artificial heart? - Human heart.ppt

The structure of the heart

Slides: 15 Words: 237 Sounds: 0 Effects: 29

The structure of the heart. Aristotle. William Harvey. The structure of the heart of fish. The structure of the heart of amphibians. The structure of the heart of reptiles. The structure of the heart of birds. The structure of the mammalian heart. Circulatory system person. Find the top of the heart. Determine the size of the heart. What is the heart covered with? What is the significance of the fluid secreted by the formation covering the heart? Define the right and left halves of the heart. Name the chambers of the heart. Locate the aorta, the largest artery, and the pulmonary artery. Locate the vessels that flow into the right and left halves of the heart. Locate the flap valves in the pictures. - The structure of the heart.ppt

The work of the heart

Slides: 11 Words: 732 Sounds: 0 Effects: 21

Structure and function of the heart. What is a heart? Is the stone hard? An apple with crimson red skin? The structure of the heart. The heart has four chambers - two atria and two ventricles. The muscular wall of the ventricles is much thicker than the wall of the atria. The middle layer (myocardium) is a powerful muscle layer. The inner layer (endocardium) is the inner epithelial layer. The heart is located almost in the center of the chest cavity and is slightly shifted to the left. Label the parts of the heart with numbers. Interesting to know… Cardiac cycle. Blood from the atria enters the ventricles. Blood from the ventricles enters the pulmonary artery and aorta. - Work of the heart.ppt

The work of the human heart

Slides: 15 Words: 1104 Sounds: 0 Effects: 31

The structure and work of the heart

Slides: 15 Words: 510 Sounds: 1 Effects: 23

"The structure and work of the heart." Cultivate hygiene skills of cardio-vascular system. What is a heart? Is the stone hard? An apple with crimson skin? E. Mezhelaitis. Remember the structural features of the heart of fish, amphibians, reptiles, birds, mammals? Location of the heart in the chest. Cardiac cycle - 0.8 s Atrial contraction - 0.1 s Ventricular contraction - 0.3 s Relaxation of the ventricles and atria - 0.4 s. Blood vessels Arteries are vessels that carry blood away from the heart. Veins are vessels that carry blood to the heart. Capillaries are the smallest blood vessels, 50 times thinner than a human hair. - The structure and work of the heart.ppt

Cardiac system

Slides: 7 Words: 162 Sounds: 0 Effects: 0

Hygiene of the cardiovascular system. Learn to justify the harmful effects of alcohol, nicotine, physical inactivity on the cardiovascular system. Major diseases of the cardiovascular system. Hypertension, angina pectoris, arrhythmia, myocardial infarction, etc. The effect of smoking: vasospasm, impaired blood supply to organs, gangrene of the legs, etc. Hypodynamia - insufficient physical activity. Stop smoking and alcohol abuse. Avoidance of stress, overwork and other negative situations. Rational and balanced nutrition. - Cardiac system.ppt

The cardiovascular system

Slides: 10 Words: 405 Sounds: 0 Effects: 0

Introduction. Based on the data obtained, we find the index of the step test. Harvard step test. A heart. It is located in the chest retrosternally. Provides blood flow through the blood vessels. The work of the heart is described by mechanical phenomena (suction and expulsion). Possesses automaticity. The wall of the heart consists of three layers - epicardium, myocardium and endocardium. Location of the heart. The form is determined by age, gender, physique, health, and other factors. The mass of the heart is approximately 220-300 g. The human cardiovascular system. Blood vessels are divided into: Arteries, arterioles, capillaries, venules, veins. - Cardiovascular system.ppt

Effect on the cardiovascular system

Slides: 23 Words: 879 Sounds: 0 Effects: 90

The state of the cardiovascular system

Slides: 31 Words: 1304 Sounds: 0 Effects: 2

Hygiene. The quality of the state of the cardiovascular system. Value for health. The mechanism of movement of blood through the vessels. Bio shootout. The movement of blood through the vessels. Arterial blood pressure. Hygiene of the cardiovascular system. Arrhythmia. The state of the cardiovascular system. Active lifestyle. Mass of the heart. The effect of smoking on the heart. The heart has to work harder. Effect of alcohol on the heart. Cough. Knowledge of the effects of alcohol. The effect of drugs on the cardiovascular system. Decreased functions of the cardiovascular system. Myocardial infarction. - The state of the cardiovascular system.ppt

The structure of the human heart

Slides: 16 Words: 831 Sounds: 0 Effects: 43

A heart. Phases of the cardiac cycle. Formation of knowledge and concepts about the structure of the heart. Knowledge about the circulatory system. Engine of human life. Human heart. High performance of the heart. The structure of the human heart. Chamber walls. Systole. The time of the contraction of the heart. The performance of the heart. An experience of reviving an isolated heart. Automation. Adrenalin. Literature. - The structure of the human heart.ppt

Diagram of the structure of the heart

Slides: 22 Words: 982 Sounds: 0 Effects: 1

Structure and function of the heart. Knowledge about the structure and function of the heart. Set a match. Mutual verification of the task. Physician Claudius Galen. Renaissance scientist. William Harvey. Circulatory system. Location of the heart. External structure of the heart. The structure of the wall of the heart. Internal structure hearts. Cardiac cycle. phase of the cardiac cycle. The solution of the problem. Structure and functions blood vessels. capillaries. Circles of blood circulation. Questions. Small circle. Monument to the heart. Homework. - Diagram of the structure of the heart.ppt

The structure and work of the human heart

Slides: 8 Words: 163 Sounds: 0 Effects: 6

Presentation. On the topic: "The structure and work of the heart." For a life medium duration approximately 5.7 million liters of blood. The main function of the heart is to pump and circulate blood throughout the body. Movement must be provided continuously. The heart muscles are nourished by the coronary (coronary) vessels. Phases of the cardiac cycle The duration of the cardiac cycle is 0.8 sec. Regulation of the heart. - The structure and work of the human heart.pptx

Neurohumoral regulation of the heart

Slides: 31 Words: 2608 Sounds: 0 Effects: 127

Neurohumoral regulation of the activity of the heart. Humoral regulation. Neurohumoral regulation of the heart. The mechanism of action of catecholamines. positive effects. The mechanism of action of acetylcholine. negative effects. Influence of thyroid hormones. Influence of corticosteroids. Influence of changes in the extracellular concentration of potassium ions. Influence of changes in the extracellular concentration of calcium ions. endocrine function of the heart. Changes in intracellular metabolic processes. Frank-Starling law. The essence of the Frank-Starling law. The essence of the Anrep effect. The Boudici phenomenon. Influence on the activity of the heart of the cerebral cortex. -

Selfless or greedy

smart or stupid

Responsive

Generous, open or callous, deaf

Stone or sensitive

Bold, proud or evil

good or hard

Black heart or gold

Mother's heart or friend's heart

slide 2

What is my heart like?

• During the day, it is reduced by about 100 thousand times, pumping more than
• 7 thousand liters blood, by spending E, this is equivalent to raising a railway freight car to a height of 1 m.
• Makes 40 million strokes in a year.
• During a person's life, it is reduced 25 billion times. This work is enough to lift the train up Mont Blanc.
• Weight - 300 g, which is 1\200 body weight, but 1\20 of all energy resources of the body are spent on its work.
• Size - with a clenched fist of the left hand.

slide 3

A TASK

• It is known that the human heart contracts on average 70 times per minute, with each contraction throwing out about 150 cubic meters. see blood. How much blood does your heart pump in 6 lessons?

SOLUTION.

• 70 x 40 = 2800 times reduced in 1 lesson.
• 2800 x150 = 420.000 cubic meters see = 420 l. blood is pumped for 1 lesson.
• 420 l. x 6 lessons = 2520 l. blood is pumped for 6 lessons.

slide 4

What explains such a high efficiency of the heart?

Pericardium

• (pericardial bag) is a thin and dense shell that forms a closed bag that covers the heart from the outside.
• Between it and the heart is a fluid that moisturizes the heart and reduces friction during contraction.

Coronary (coronary) vessels

• vessels feeding the heart itself (10% of the total volume)

slide 5

slide 6

The walls of the chambers consist of cardiac muscle fibers - myocardium, connective tissue and numerous blood vessels

• The chamber walls vary in thickness. The thickness of the left ventricle is 2.5 - 3 times thicker than the walls of the right
• Valves provide movement in exactly one direction.
• Valves between the atria and ventricles
• Double doors on the left side
• Tricuspid on the right side
• Semilunar between the ventricles and arteries, consist of 3 pockets

Slide 7

The cardiac cycle is the sequence of events that occur during one heartbeat. Duration less than 0.8 sec.

• atrium
  • Systole (contraction)
  • Diastole (relaxation)
  • Diastole (relaxation)
  • Systole - 0.1 s.
  • Diastole - 0.7 s.
• Ventricles
  • Diastole (relaxation)
  • Systole (contraction)
  • Diastole (relaxation)
  • Systole - 0.3 s. Distola - 0.5 s.
• Phase I The flap valves are open. Lunar - closed. Duration - 0.1 s.
• Phase II The flap valves are closed. Duration - 0.3 s
• Phase III Diastole, complete relaxation of the heart. Duration - 0.4 s.

Slide 8

Knowing the cardiac cycle and the time of heart contraction in 1 min (70 beats), it can be determined that out of 80 years of life:

• ventricular muscles rest - 50 years.
• atrial muscles rest - 70 years.

Slide 9

High performance of the heart is due to

• high level metabolic processes taking place in the heart;
• Increased blood supply to the heart muscles;
• The strict rhythm of its activity (the phases of work and rest of each department strictly alternate)

Slide 10

AUTOMATIC

• The experience of reviving an isolated human heart for the first time in the world was successfully carried out by the Russian scientist A. A. Kulyabko in 1902 - he revived the heart of a child 20 hours after death from pneumonia.
• What is the reason?

slide 11

Automation is the ability of the heart to contract rhythmically regardless of external influences, but only due to impulses that occur in the heart muscle.

• Location: special muscle cells of the right atrium

slide 12

• During physical and emotional stress, the heart pumps, on average, 3-5 times more blood per minute than at rest.
• Adrenaline (adrenal hormone), calcium salts and other biologically active substances increase the frequency and strength of heart contractions.
• Potassium ions, bradykinin and other biologically active substances reduce the frequency and strength of heart contractions.
• Bradykinin is a peptide formed from plasma proteins under the action of proteolytic enzymes (trypsin, snake venom enzymes). Causes smooth muscle relaxation arterial pressure, increases the permeability of blood vessels, which leads to the appearance of edema, causes a feeling of pain.
• Parasympathetic nerves reduce the frequency and strength of heart contractions, reducing the speed of blood flow in the vessels.
• Sympathetic nerves increase the rate and force of heart contractions.

View all slides