Why do lesions in the lungs occur and why are they dangerous? How to check your lungs? Methods for examining the lungs Types and methods for examining the lungs

Lesson outline

Leading Concepts

Urine.
Urea.
An artificial kidney is a device that can cleanse the body of toxins when one’s own kidneys fail for a while (during surgery, in case of sublimate poisoning).
Nephritis is an inflammation of the kidneys primarily affecting the glomeruli.
Pyelitis is inflammation of the renal pelvis.

Issues for discussion

1. Can the lungs and skin be classified as excretory organs? Give a reasoned answer.
2. Why does the presence of protein or sugar in the urine indicate possible kidney disease?
3. Why does the amount of urine increase in cold weather?
4. What conditions negatively affect the normal functioning of the kidneys?
5. What, in your opinion, is the fundamental difference between excrement and excrement?

Topic 7. Skin

Planning a theme

Lesson 1.

Structure and functions of the skin

1. Skin is a mirror of health:
– elastic, smooth skin (healthy body);
– lethargic, swollen, pale (illness, age);
– skin with a icteric coloration (with liver disease);
– edematous, with a bluish color (in case of cardiac dysfunction);
– skin with a grayish, earthy color (with gastrointestinal diseases);
– allergic reactions.
2. Skin is a border organ that separates the body from the external environment:
– protection from damage and penetration of microbes;
– participation in thermoregulation;
– excretory and respiratory functions;
– participation in the implementation of reflexes associated with the presence of receptors in the skin (per 1 cm2 of skin there are 100–200 pain points, 12–15 cold points, 1–2 heat points and about 25 pressure points).
3. The structure of the skin, the relationship between the structure of the skin and the functions it performs:
– epidermis;
– the skin itself (dermis);
– subcutaneous fatty tissue;
– hair and nails are derivatives of the skin;
– the role of sweat and sebaceous glands; mammary gland is a modified sweat gland.
4. Skin color:
– dependence of skin color on the amount of melanin pigment;
– fluctuations in the amount of melanin in different races and nationalities;
– different amounts of melanin in the skin of blondes and brunettes;
– protective function of melanin.
5. Features of facial skin, connection with facial muscles.

Lesson 1 outline

Leading Concepts

Epidermis.
Dermis.
Subcutaneous fatty tissue.
Receptors.
Exocrine glands.
Melanin.
Functions of the skin.
The relationship between structure and function.
The body is a single whole.

Issues for discussion

1. Why does the body lose salts when drinking a lot of water?
2. What is the protective function of the skin?
3. Is it really possible to “breathe easier” after a bath?
4. Is it possible to “achieve” greater facial expression with special exercises?
5. Thin people freeze faster than fat people. Why?

Search tasks (additional information)

Lesson 2.

The role of the skin in thermoregulation. First aid for overheating, burns and frostbite

1. Constant body temperature and relative independence of warm-blooded animals from changes in ambient temperature.
2. Energy exchange and heat generation. Methods of heat transfer. The meaning of sweating. Steam generation consumption.
3. Thermoregulation – maintaining a balance between the amount of heat generated in the body and its release to the external environment.
4. Neurohumoral regulation of increasing or decreasing heat production and heat transfer.
5. Conditions that promote and hinder thermoregulation (air humidity, ambient temperature, hygienic condition of the skin, clothing).
6. Symptoms and first aid for heat and sunstroke. Prevention of heat and sunstroke.
7. First aid for burns and frostbite.

Lesson 2 outline

Leading Concepts

Heat dissipation.
Thermoregulation.
Heatstroke is a violation of thermoregulation when the body overheats and difficulty transferring heat.

Issues for discussion

1. Why does a person who has been in cold water for a long time turn blue and tremble?
2. Which climate is more difficult to tolerate and why: hot humid or hot dry?
3. Why can a drunk person freeze and die after falling asleep in the cold?
4. Why is it better to drink lightly salted water in hot shops?
5. Some people get cold easily. Explain how this may be related to a violation of the body's thermoregulation.

Lesson 3.

Skin hygiene. Hardening the body

1. Functions of the skin. The relationship between the structure of the skin and its function.
2. Sweating. Composition of sweat. Hygienic rules for skin care. Features of skin care during adolescence.
3. Hair and nail hygiene.
4. Hygiene of clothing and shoes.
5. Hardening is a complex of effects on the body that increases the ability to regulate heat and resistance to diseases.
6. Colds and their causes. Hardening factors: air, water, sun.
7. Methods of hardening.

Lesson outline 3

Leading Concepts

Hygiene.
Hardening.
The body is a single whole.
Hardening factors.
Hardening methods.

Issues for discussion

1. Create skin care rules. Explain how the requirements of skin hygiene correspond to its functions?
2. What functions of the skin are associated with the basic hygienic requirements for clothing?
3. Skin is a mirror of health. Is this statement correct and why?
4. Hardening is a complex of effects on the body. Why is the concept of “hardening” associated with the concept of “skin”?
5. During hardening, the nervous system and blood vessels are trained. How do you understand this?

Lesson 4.

Interrelation of organ systems in the process of human life (summarizing)

1. Features of the structure of the circulatory system that ensure a constant temperature of the human body (and warm-blooded animals).
2. Food is a source of energy. The role of proteins, fats and carbohydrates in food as sources of energy.
3. The importance of plastic and energy exchange occurring in the cell to ensure the vital processes of the entire organism.
4. The relationship between the circulatory, respiratory and digestive systems and their role in providing the body with energy.
5. Participation of the circulatory, respiratory systems and skin in the removal of decay products.
6. The influence of various conditions (load, overheating, cooling) on ​​metabolism. The role of thermoregulation.
7. Conclusion about the organism as a single whole, influenced by environmental conditions.

Lesson outline 4

Verification work

Prove the dependence of the human body on vital resources by filling out the table.

Reference

The second law of thermodynamics: during any transformation of energy, part of it is lost in the form of heat.

Topic 8. Endocrine glands

Planning a theme

Comparative characteristics of the glands of the human body (Additional Information)

Lesson 1.

Biologically active substances and their role in the body.
Hormones – biological regulators

1. Biologically active substances:
a) enzymes – biological catalysts;
b) vitamins – participate in the formation of enzymes;
c) hormones – biological regulators.
2. Properties of hormones:
a) action in small concentrations;
b) exposure through blood and lymph;
c) strict direction of action.
3. Participation of hormones in the humoral regulation of body functions. Comparative characteristics of humoral and nervous regulation.

Lesson 1 outline

Leading Concepts

Enzymes.
Vitamins.
Hormones.
Neurohumoral regulation.
The body is a single whole.

Independent work

Select the appropriate characteristics and enter them into the table.

Comparative characteristics of nervous and humoral regulation

Signs for comparison.

1. A more ancient form of interaction.
2. Signals are transmitted at high speed - up to 100 m/s.
3. Signal transmission occurs through blood or lymph.
4. The signal travels exactly to the recipient.
5. Communication is carried out according to the principle “everyone, everyone, everyone!”
6. The signal is a nerve impulse.
7. The signal is a chemical substance.
8. The signal lasts longer.

Lesson 2.

Intrasecretory activity of the endocrine glands

1. The concept of external and internal secretion glands, mixed glands.
2. The relationship between the structure and function of various glands:
a) the presence of excretory ducts;
b) release of secretions (into the blood or into the cavity);
c) functions of the glands (participation in the process of digestion, excretion - exocrine glands and mixed glands; participation in humoral regulation - endocrine glands and mixed glands).
3. The function of the endocrine glands is the action of hormones through the blood.
4. Functions of the adrenal glands and the hormone adrenaline.
5. Intrasecretory function of the pancreas. The role of the hormone insulin.
6. Thyroid gland. Pituitary. The role of the gonads in the development of the body. Primary and secondary sexual characteristics.
7. Disturbances in the activity of the endocrine glands.

Reference

Testosterone is a male sex hormone produced by the testes.
The ovaries produce several female sex hormones (estrogen, progesterone).
A group of male sex hormones (androgens) are formed not only in the testes, but also in the ovaries and adrenal cortex of both sexes.

Leading Concepts

The gland is an organ that produces and secretes special substances - secretions that participate in the physiological processes of the body. Endocrine gland.
Hormone.
Neurohumoral regulation

Independent work

Topic 9. Nervous system. Sense organs. Higher nervous activity

Planning a theme

Lesson 1.

Structure and functions of the nervous system

1. Central and peripheral nervous system. The relationship between structure and function.
2. Functions of the nervous system:
a) regulates the work of organs;
b) coordinates the work of cells, tissues, organs and their systems as a whole;
c) ensures the relationship of the organism with the external environment;
d) is the basis of human mental functions: thinking, consciousness, speech.
3. Excitation and inhibition. The role of nerve impulses in the implementation of nervous regulation.
4. Comparative characteristics of the functions of the nervous system of animals and humans.

Lesson 1 outline

Leading Concepts

Excitability is the ability of cells to excite.
Excitation is the transition of any living system from a state of relative physiological rest to active activity (conditioned and unconditioned reflex).
Inhibition is a nervous process expressed in the delay of excitation in response to irritation or in a decrease in the intensity of excitation that has already arisen in the cerebral cortex.
Conditioned reflex.
Unconditioned reflex.
Functions of the nervous system.

Issues for discussion

1. What properties does nervous tissue have? Give specific examples that support these properties.
2. Prove that the nervous system ensures the functioning of organs in accordance with the needs of the body.
3. What state will the hand be in if the centers regulating the biceps and triceps muscles are excited?

Lesson 2.

Spinal cord. Autonomic nervous system

1. Structure of the spinal cord:
a) location of the spinal cord in the spinal canal;
b) spinal canal;
c) location of gray and white matter;
d) nerves extending from the spinal cord;
e) the location of ascending and descending pathways in the white matter and intercalary and executive neurons in the gray matter.
2. Functions of the spinal cord:
a) reflex (unconditioned reflexes);
b) conductor.
3. Regulation by the brain of the activity of the spinal cord.
4. Division of the nervous system according to functional characteristics:
a) somatic;
b) vegetative.

Lesson 2 outline

Leading Concepts

Spinal reflexes
Spinal nerves.
Anterior and posterior roots of the spinal cord.
Somatic nervous system.
Autonomic nervous system.
Sympathetic department.
Parasympathetic department.

Issues for discussion

1. What are the dangers of spinal cord injuries?
2. The autonomic nervous system has its own centers, nerve nodes and nerves. Give examples of the opposite action of autonomic nerve centers on organs.
3. Give examples of organs whose function is regulated by the autonomic nervous system and organs regulated by the somatic nervous system.
4. The body is a single whole. Explain whether the activities of the autonomic and somatic parts of the nervous system are connected.

Lesson 3.

Structure and functions of the brain

1. Structure of the brain:
a) parts of the brain;
b) distribution of gray and white matter;
c) cortex, nuclei, pathways.
2. Unconditional reflex activity of the medulla oblongata, pons and midbrain.
3. The activity of the cerebellum, subordinate to the centers of the cerebral cortex.
4. Forebrain:
a) diencephalon;
b) cerebral hemispheres.
5. Structure and functions of the cerebral hemispheres:
a) gray matter (cortex);
b) white matter, which has accumulations of gray matter (nerve centers).
6. Subcortical centers and emotions:
a) dependence of the manifestation of emotions on subcortical centers;
b) the influence of positive and negative emotions on the functioning of organs.
7. Cerebral cortex:
a) lobes of the cerebral hemispheres and their functions;
b) physiological processes of the cerebral cortex associated with mental functions (attention, memory, thinking, etc.).
8. Brain disorders:
a) hereditary diseases;
b) disturbances caused by environmental factors.

Lesson outline 3

Leading Concepts

Divisions of the brain.
Functions of brain parts.
Conditioned and unconditioned reflex activity.
The brain is the material basis of human mental activity.
The hypothalamus is the “endocrine brain”, a section of the diencephalon.

Independent work

Fill in the third column of the table using the textbook text.

Brain functions

To be continued

Selection- a set of physiological processes aimed at removing metabolic end products from the body (carried out by the kidneys, sweat glands, lungs, gastrointestinal tract, etc.).

Excretion) - the process of liberating the body from the end products of metabolism, excess water, minerals (macro- and microelements), nutrients, foreign and toxic substances and heat. The release occurs constantly in the body, which ensures the maintenance of the optimal composition and physicochemical properties of its internal environment and, above all, blood.

The end products of metabolism (metabolism) are carbon dioxide, water, nitrogen-containing substances (ammonia, urea, creatinine, uric acid). Carbon dioxide and water are formed during the oxidation of carbohydrates, fats and proteins and are released from the body mainly in free form. A small portion of carbon dioxide is released as bicarbonates. Nitrogen-containing metabolic products are formed during the breakdown of proteins and nucleic acids. Ammonia is formed during the oxidation of proteins and is removed from the body mainly in the form of urea (25-35 g/day) after appropriate transformations in the liver and ammonium salts (0.3-1.2 g/day). In the muscles, during the breakdown of creatine phosphate, creatine is formed, which, after dehydration, is converted into creatinine (up to 1.5 g/day) and in this form is removed from the body. When nucleic acids break down, uric acid is formed.

During the oxidation of nutrients, heat is always released, the excess of which must be removed from the place of its formation in the body. These substances formed as a result of metabolic processes must be constantly removed from the body, and excess heat must be dissipated into the external environment.

Human excretory organs

The process of excretion is important for homeostasis; it ensures the release of the body from metabolic end products that can no longer be used, foreign and toxic substances, as well as excess water, salts and organic compounds received from food or formed as a result of metabolism. The main importance of the excretory organs is to maintain a constant composition and volume of fluid in the internal environment of the body, primarily blood.

Excretory organs:

• kidneys - remove excess water, inorganic and organic substances, end products of metabolism;
• lungs- remove carbon dioxide, water, some volatile substances, for example, ether and chloroform vapors during anesthesia, alcohol vapors during intoxication;
• salivary and gastric glands- release heavy metals, a number of drugs (morphine, quinine) and foreign organic compounds;
• pancreas and intestinal glands - excrete heavy metals and drugs;
• skin (sweat glands) - They secrete water, salts, some organic substances, in particular urea, and during hard work, lactic acid.

General characteristics of the extraction system

Selection system - This is a collection of organs (kidneys, lungs, skin, digestive tract) and regulatory mechanisms, the function of which is the excretion of various substances and the dissipation of excess heat from the body into the environment.

Each of the organs of the excretory system plays a leading role in removing certain excreted substances and dissipating heat. However, the efficiency of the excretion system is achieved through their joint work, which is ensured by complex regulatory mechanisms. In this case, a change in the functional state of one of the excretory organs (due to its damage, disease, exhaustion of reserves) is accompanied by a change in the excretory function of others included in the body’s integral excretory system. For example, with excessive excretion of water through the skin with increased sweating under conditions of high external temperature (in the summer or while working in hot workshops in production), the formation of urine by the kidneys and its excretion decreases - diuresis decreases. With a decrease in the excretion of nitrogenous compounds in the urine (in case of kidney disease), their removal through the lungs, skin, and digestive tract increases. This is the cause of “uremic” breath odor in patients with severe forms of acute or chronic renal failure.

Kidneys play a leading role in the excretion of nitrogen-containing substances, water (under normal conditions, more than half of its volume from the daily excretion), excess of most minerals (sodium, potassium, phosphates, etc.), excess of nutrients and foreign substances.

Lungs ensure the removal of more than 90% of carbon dioxide formed in the body, water vapor, and some volatile substances that enter or are formed in the body (alcohol, ether, chloroform, gases from vehicles and industrial enterprises, acetone, urea, surfactant degradation products). When kidney function is impaired, the secretion of urea from the secretions of the respiratory tract glands increases, the decomposition of which leads to the formation of ammonia, which causes the appearance of a specific odor from the mouth.

Glands of the digestive tract(including the salivary glands) play a leading role in the secretion of excess calcium, bilirubin, bile acids, cholesterol and its derivatives. They can release heavy metal salts, drugs (morphine, quinine, salicylates), foreign organic compounds (for example, dyes), small amounts of water (100-200 ml), urea and uric acid. Their excretory function increases when the body is overloaded with an excessive amount of various substances, as well as in kidney diseases. At the same time, the excretion of protein metabolic products with the secretions of the digestive glands increases significantly.

Leather has a leading role in the processes of heat transfer by the body to the environment. The skin has special excretory organs - sweat and sebaceous glands. Sweat glands play an important role in the release of water, especially in hot climates and (or) intense physical work, including in hot shops. The release of water from the surface of the skin ranges from 0.5 l/day at rest to 10 l/day on hot days. Sodium, potassium, calcium salts, urea (5-10% of the total amount excreted from the body), uric acid, and about 2% carbon dioxide are also released with sweat. Sebaceous glands secrete a special fatty substance - sebum, which performs a protective function. It consists of 2/3 water and 1/3 unsaponifiable compounds - cholesterol, squalene, metabolic products of sex hormones, corticosteroids, etc.

Functions of the excretory system

Excretion is the liberation of the body from metabolic end products, foreign substances, harmful products, toxins, and medicinal substances. As a result of metabolism in the body, end products are formed that cannot be further used by the body and therefore must be removed from it. Some of these products are toxic to the excretory organs, so mechanisms are formed in the body aimed at converting these harmful substances either into harmless or less harmful to the body. For example, ammonia, formed during protein metabolism, has a harmful effect on renal epithelial cells, so in the liver ammonia is converted into urea, which does not have a harmful effect on the kidneys. In addition, the liver neutralizes toxic substances such as phenol, indole and skatole. These substances combine with sulfuric and glucuronic acids, forming less toxic substances. Thus, the processes of excretion are preceded by the processes of so-called protective synthesis, i.e. converting harmful substances into harmless ones.

Excretory organs include: kidneys, lungs, gastrointestinal tract, sweat glands. All these organs perform the following important functions: removal of metabolic products; participation in maintaining the constancy of the internal environment of the body.

Participation of excretory organs in maintaining water-salt balance

Functions of water: water creates an environment in which all metabolic processes take place; is part of the structure of all body cells (bound water).

The human body consists of 65-70% water. In particular, a person with an average weight of 70 kg has about 45 liters of water in the body. Of this amount, 32 liters is intracellular water, which is involved in building the structure of cells, and 13 liters is extracellular water, of which 4.5 liters is blood and 8.5 liters is intercellular fluid. The human body constantly loses water. About 1.5 liters of water are excreted through the kidneys, which dilutes toxic substances, reducing their toxic effect. About 0.5 liters of water per day are lost through sweat. The exhaled air is saturated with water vapor and 0.35 liters are removed in this form. About 0.15 liters of water are removed with the final products of food digestion. Thus, about 2.5 liters of water are removed from the body during the day. To maintain water balance, the same amount must enter the body: about 2 liters of water enter the body with food and drink, and 0.5 liters of water are formed in the body as a result of metabolism (exchange water), i.e. the water flow is 2.5 liters.

Regulation of water balance. Autoregulation

This process starts with a deviation in the water content constant in the body. The amount of water in the body is a rigid constant, since with insufficient water supply a shift in pH and osmotic pressure occurs very quickly, which leads to a profound disruption of the metabolism in the cell. A subjective feeling of thirst signals an imbalance in the body's water balance. It occurs when there is insufficient intake of water into the body or when it is released excessively (increased sweating, dyspepsia, when there is an excess intake of mineral salts, i.e., with an increase in osmotic pressure).

In various parts of the vascular bed, especially in the hypothalamus (in the supraoptic nucleus), there are specific cells - osmoreceptors containing a vacuole (vesicle) filled with liquid. These cells are surrounded by a capillary vessel. When the osmotic pressure of the blood increases, due to the difference in osmotic pressure, fluid from the vacuole will leak into the blood. The release of water from the vacuole leads to its shrinkage, which causes excitation of osmoreceptor cells. In addition, there is a feeling of dryness in the mucous membrane of the mouth and pharynx, while the receptors of the mucous membrane are irritated, impulses from which also enter the hypothalamus and increase the excitation of a group of nuclei called the thirst center. Nerve impulses from them enter the cerebral cortex and a subjective feeling of thirst is formed there.

With an increase in blood osmotic pressure, reactions begin to form that are aimed at restoring the constant. Initially, reserve water from all water depots is used, it begins to pass into the blood, in addition, irritation of the osmoreceptors of the hypothalamus stimulates the release of ADH. It is synthesized in the hypothalamus and deposited in the posterior lobe of the pituitary gland. The release of this hormone leads to a decrease in diuresis by increasing the reabsorption of water in the kidneys (especially in the collecting ducts). Thus, the body is freed from excess salts with minimal water loss. Based on the subjective sensation of thirst (thirst motivation), behavioral reactions are formed aimed at searching for and receiving water, which leads to a rapid return of the osmotic pressure constant to a normal level. This is how the process of regulating a rigid constant is carried out.

Water saturation occurs in two phases:

• phase of sensory saturation, occurs when water irritates the receptors of the mucous membrane of the oral cavity and pharynx, deposited water is released into the blood;
• the phase of true or metabolic saturation occurs as a result of the absorption of ingested water in the small intestine and its entry into the blood.

Excretory function of various organs and systems

The excretory function of the digestive tract is not only limited to removing undigested food debris. For example, in patients with nephritis, nitrogenous wastes are removed. When tissue respiration is impaired, underoxidized products of complex organic substances also appear in saliva. In case of poisoning in patients with symptoms of uremia, hypersalivation (increased salivation) is observed, which to a certain extent can be considered as an additional excretory mechanism.

Some dyes (methylene blue or congorot) are released through the gastric mucosa, which is used to diagnose gastric diseases during simultaneous gastroscopy. In addition, salts of heavy metals and medicinal substances are removed through the gastric mucosa.

The pancreas and intestinal glands also excrete heavy metal salts, purines and drugs.

Excretory function of the lungs

With exhaled air, the lungs remove carbon dioxide and water. In addition, most aromatic esters are removed through the alveoli of the lungs. Fusel oils are also removed through the lungs (intoxication).

Excretory function of the skin

During normal functioning, the sebaceous glands secrete metabolic end products. The secretion of the sebaceous glands serves to lubricate the skin with fat. The excretory function of the mammary glands manifests itself during lactation. Therefore, when toxic and medicinal substances and essential oils enter the mother’s body, they are released into the milk and can have an effect on the child’s body.

The actual excretory organs of the skin are the sweat glands, which remove waste products of metabolism and thereby participate in maintaining many constants of the internal environment of the body. With sweat, water, salts, lactic and uric acids, urea, and creatinine are removed from the body. Normally, the share of sweat glands in removing the products of protein metabolism is small, but in kidney diseases, especially acute renal failure, the sweat glands significantly increase the volume of excreted products as a result of increased sweating (up to 2 liters or more) and a significant increase in the urea content in sweat. Sometimes so much urea is removed that it is deposited in the form of crystals on the patient’s body and underwear. Sweat can remove toxins and drugs. For some substances, the sweat glands are the only organ of excretion (for example, arsenous acid, mercury). These substances, released through sweat, accumulate in the hair follicles and integument, which makes it possible to determine the presence of these substances in the body even many years after its death.

Excretory function of the kidneys

The kidneys are the main excretory organs. They play a leading role in maintaining a constant internal environment (homeostasis).

The functions of the kidneys are very extensive and involve:

• in regulating the volume of blood and other fluids that make up the internal environment of the body;
• regulate constant osmotic pressure of blood and other body fluids;
• regulate the ionic composition of the internal environment;
• regulate acid-base balance;
• provide regulation of the release of end products of nitrogen metabolism;
• provide excretion of excess organic substances supplied with food and formed during metabolism (for example, glucose or amino acids);
• regulate metabolism (metabolism of proteins, fats and carbohydrates);
• participate in the regulation of blood pressure;
• participate in the regulation of erythropoiesis;
• participate in the regulation of blood clotting;
• participate in the secretion of enzymes and physiologically active substances: renin, bradykinin, prostaglandins, vitamin D.

The structural and functional unit of the kidney is the nephron, in which the process of urine formation occurs. Each kidney has about 1 million nephrons.

The formation of final urine is the result of three main processes occurring in the nephron: and secretion.

Glomerular filtration

Urine formation in the kidneys begins with the filtration of blood plasma in the glomeruli. There are three barriers to the filtration of water and low molecular weight compounds: the endothelium of the glomerular capillaries; basement membrane; inner layer of the glomerular capsule.

At normal blood flow rates, large protein molecules form a barrier layer on the surface of the endothelial pores, preventing the passage of formed elements and fine proteins through them. Low molecular weight components of blood plasma could freely reach the basement membrane, which is one of the most important components of the glomerular filtering membrane. Pores in the basement membrane restrict the passage of molecules based on their size, shape, and charge. The negatively charged pore wall makes it difficult for molecules with the same charge to pass through and limits the passage of molecules larger than 4-5 nm. The last barrier to the filtered substances is the inner layer of the glomerular capsule, which is formed by epithelial cells - podocytes. Podocytes have processes (feet) with which they attach to the basement membrane. The space between the legs is blocked by slit membranes, which limit the passage of albumin and other molecules with a large molecular weight. Thus, such a multilayer filter ensures the preservation of formed elements and proteins in the blood, and the formation of a practically protein-free ultrafiltrate - primary urine.

The main force providing filtration in the renal glomeruli is the hydrostatic pressure of the blood in the capillaries of the glomerulus. The effective filtration pressure, on which the glomerular filtration rate depends, is determined by the difference between the hydrostatic blood pressure in the capillaries of the glomerulus (70 mm Hg) and the factors counteracting it - the oncotic pressure of plasma proteins (30 mm Hg) and the hydrostatic pressure of the ultrafiltrate in glomerular capsule (20 mm Hg). Therefore, the effective filtration pressure is 20 mmHg. Art. (70 - 30 - 20 = 20).

The amount of filtration is influenced by various intrarenal and extrarenal factors.

Renal factors include: the magnitude of hydrostatic blood pressure in the capillaries of the glomerulus; number of functioning glomeruli; the pressure value of the ultrafiltrate in the glomerular capsule; degree of permeability of glomerular capillaries.

Extrarenal factors include: blood pressure in the great vessels (aorta, renal artery); renal blood flow velocity; the value of oncotic blood pressure; functional state of other excretory organs; degree of tissue hydration (amount of water).

Tubular reabsorption

Reabsorption is the reabsorption of water and substances necessary for the body from primary urine into the blood. In the human kidneys, 150-180 liters of filtrate or primary urine are formed per day. About 1.5 liters of final or secondary urine are excreted, the rest of the liquid part (i.e. 178.5 liters) is absorbed in the tubules and collecting ducts. Reabsorption of various substances is carried out due to active and passive transport. If a substance is reabsorbed against a concentration and electrochemical gradient (i.e., with the expenditure of energy), then this process is called active transport. There are primary active and secondary active transport. Primary active transport is the transfer of substances against an electrochemical gradient and is carried out using the energy of cellular metabolism. Example: the transfer of sodium ions, which occurs with the participation of the enzyme sodium-potassium ATPase, which uses the energy of adenosine triphosphate. Secondary active transport is the transfer of substances against a concentration gradient, but without the expenditure of cell energy. Using this mechanism, glucose and amino acids are reabsorbed.

Passive transport occurs without energy consumption and is characterized by the fact that the transfer of substances occurs along an electrochemical, concentration and osmotic gradient. Due to passive transport, the following are reabsorbed: water, carbon dioxide, urea, chlorides.

The reabsorption of substances in different parts of the nephron is not the same. In the proximal segment of the nephron, glucose, amino acids, vitamins, trace elements, sodium and chlorine are reabsorbed from the ultrafiltrate under normal conditions. In subsequent sections of the nephron, only ions and water are reabsorbed.

The functioning of the rotary-countercurrent system is of great importance in the reabsorption of water and sodium ions, as well as in the mechanisms of urine concentration. The nephron loop has two branches - descending and ascending. The epithelium of the ascending knee has the ability to actively transfer sodium ions into the intercellular fluid, but the wall of this section is impermeable to water. The epithelium of the descending limb allows water to pass through, but does not have mechanisms for transporting sodium ions. Passing through the descending part of the nephron loop and releasing water, primary urine becomes more concentrated. Reabsorption of water occurs passively due to the fact that in the ascending section there is an active reabsorption of sodium ions, which, entering the intercellular fluid, increase the osmotic pressure in it and promote the reabsorption of water from the descending sections.

Many smokers, especially long-term smokers, complain of a prolonged cough and some soreness in the chest. Often, in this way, the body signals that problems with the lungs have begun. What should you do if your breathing system suddenly begins to malfunction? Of course, the first thing a person does is undergo examinations using fluorography and subsequent mucus sampling for detailed analysis.

How to check the lungs, besides fluorography, what other diagnostic methods exist? Can this be done at home and what symptoms should I pay attention to? Everyone should know such nuances, not just heavy smokers. After all, it is better to notice many pathologies of the bronchopulmonary system in time and begin treatment than to allow the development of irreversible processes.

You should definitely monitor the condition of your lungs, and you can check their well-being at home

The laboratory examination plan is developed taking into account the patient’s complaints and manifested symptoms. A competent medical approach allows you to identify dangerous diseases in time, doing this with minimal discomfort for the person.

According to statistics, pathologies of the bronchopulmonary system account for about 40-50% of all modern diseases. The most common pathology is COPD (chronic obstructive pulmonary disease).

The structure of the respiratory system

Most often, these disorders affect young people aged 20-40 years. Therefore, it is extremely important to monitor your own health and treat identified diseases in a timely manner, even if it is a mild cold. Doctors, considering the main causes of bronchopulmonary diseases, include the following factors as the most common culprits in their development:

1. Passion for smoking.
2. Poor living conditions.
3. Hereditary pathologies.
4. Occupational diseases.

So, how to check the bronchi and lungs using medical methods? Instrumental diagnostics includes quite a few methods. The doctor decides which one to use based on the general condition of the patient and the characteristics of the symptoms.

Radiography

This method of examining the lungs is indicated for almost any person. The examination using an X-ray machine is carried out in two areas: lateral and direct. This research method helps the doctor not only clarify the possible disease, but also use the results of the examination in differential diagnosis.

The essence of chest radiography

But radiography has a number of contraindications. This method of studying lung health cannot be carried out in the case of:

• severe liver and kidney diseases;
• complicated condition of the patient;
• allergies to the contrast agent used;
• serious pathologies of the cardiovascular system.

Tomography

With the help of this examination, the physician receives a detailed (layer-by-layer) picture of the structure of tissues and organs of the human body. By examining an image consisting of many sections, the doctor can more accurately determine the health status of the organ being examined (in this case, the lungs). Tomography is often used to identify various areas of opacities identified on x-rays.

Tomography allows you to study layer-by-layer images of human lungs

CT (computed tomography)

This method of studying the lungs is carried out using x-rays with the connection of highly complex computer processing. The result is a high-quality image with an increased degree of resolution and clarity. Using this technique, you can check the lungs for cancer and identify any other type of disorder.. A physician, studying CT images, can determine:

• whether other organs are affected;
• how the pathological process spread;
• existing additional pathogenic processes.

MRI (magnetic resonance imaging)

This method of instrumental diagnostics is based on measuring the activity of atomic nuclei after irritation by electromagnetic waves. MRI is not performed on patients who have various metal implantations or devices implanted in the body, such as:

• pacemakers;
• Illizarova devices;
• installed middle ear prostheses;
• fragments remaining in the body after injuries;
• implants (electronic or ferromagnetic).

The MRI method allows you to more accurately diagnose pathological changes in the body

Also, MRI is not performed on pregnant women in the first trimester or if the person suffers from claustrophobia. This type of examination is contraindicated in case of mental disorders or serious condition of the patient. Using MRI, the type of neoplasm detected, the degree of its development are clarified, and various pathologies are identified in the early stages of development.

Angiography

This is an X-ray examination of the vessels of the bronchopulmonary system. The examination is carried out after preliminary injection of a special contrast agent into the blood. This method is intended to further clarify possible oncological processes. The method also allows:

• diagnose vascular aneurysms;
• detect thromboembolism of the pulmonary artery.

The essence of angiography technique

Contraindications for angiography include the same prohibitions as for x-rays. Possible intolerance to the contrast agent used is also taken into account.

Bronchography

This technique is in many ways similar to x-ray examination. With its help, possible pathologies of the bronchopulmonary tree are identified. Bronchography allows you to identify various diseases of the bronchi, identify cavities formed after lung abscesses, and determine the degree of expansion of the bronchial walls.

What is brochnography used for?

Bronchography is the least informative diagnostic method and is used quite rarely in modern medicine.

Tracheobronchoscopy

The examination is carried out using a special device, consisting of a long flexible hose and cable with a backlight function (often this device has photo and video recording functions). The doctor gets the opportunity to directly examine the condition of the mucous membrane of the trachea and bronchi and assess the health of the organs.

Using manipulators built into the end of the tube, during the examination you can remove a sample for biopsy or remove foreign bodies that have entered the respiratory tract. During the event, the patient may notice some unpleasant sensations:

• nasal congestion;
• numbness of the oral mucosa;
• difficulty swallowing;
• sensation of a lump in the larynx.

Bronchoscopy also allows for the collection of biomaterial

The culprit of such short-term troubles is anesthesia (the examination is carried out under anesthesia). All negative symptoms pass very quickly, within 50-60 minutes. But this procedure has a number of strict contraindications, in particular:

• hypertension;
• heart problems;
• vascular insufficiency;
• mental illnesses;
• suffered a stroke or heart attack;
• bronchial asthma in the relapse stage;
• allergy to the anesthetic used.

One of the varieties of this examination is fluorescent laser bronchoscopy. It is carried out if a person is suspected of having cancer. The method is based on the ability of malignant tumors to actively absorb photosubstance.

Checking your lungs at home

As already mentioned, one of the most common dangerous diseases of the bronchopulmonary system is COPD. This disease is a kind of chronic mix of obstructive bronchitis and pulmonary emphysema.

The main cause of COPD is long-term smoking. The result of the disease is the inability of the lungs to absorb oxygen, which can lead to the death of the patient.

This disease is extremely dangerous due to its latent development, especially in the first stages of the disease. But a fatal pathology that affects a smoker’s lungs can be identified in a timely manner and treatment can begin immediately. And you can do this at home using several methods.

COPD is the most common lung pathology in smokers

Checking your lung capacity

There are some signs the presence of which makes a person wonder if everything is okay with the lungs. These exercises should be performed regularly, especially for smokers. This will allow you to suspect problems as soon as they appear. So, how can you check your lung capacity and its health?

1. Hold your breath, if you can hold your exhalation for 1-1.5 minutes, this is the norm for a healthy person.
2. Take candles that are stuck into the birthday cake according to the age. A person with healthy lungs will be able to blow them out in one go, blowing at a distance of about 70-80 cm.
3. Take in as much air as possible and inflate a regular balloon. In this case, it should be inflated with one exhalation. The resulting size of the ball indicates the volume of the lungs. Normally, healthy lungs have a volume of 3.5 liters.

When to be wary

The very first sign of an impending disease is shortness of breath. Unfortunately, most smokers do not pay attention to the alarm bell, attributing difficulty breathing to age, fatigue, and the environment. But the problem with COPD is that it is impossible to completely cure the disease once it develops.. The disease can only be delayed, slowed down.

What happens to the lungs with COPD

When a smoker does not pay attention to the constant shortness of breath that develops even when walking calmly, the person’s chances of maintaining healthy lung tissue rapidly decrease.

Therefore, it is extremely important to be able to understand in time that problems are beginning with your own lungs. And the first sign is shortness of breath. Try to experiment, for example, do some physical exercise, go up/down the stairs, and then try to take a full breath.

Stay tuned for changes. If you feel unable to breathe deeply, you should conduct a comprehensive examination of the pulmonary structure.

Alarming symptoms

As the fatal pathology develops, the patient also experiences a number of other signs. Many of them appear in healthy people, but in combination with smoking they become pathological manifestations.

Cough

Even completely healthy people clear their throat from time to time. But too frequent coughing is one of the signs of COPD. Coughing leads to a constant inflammatory process in the bronchioles and alveoli, as a result of which they lose their elasticity. Over time, their walls noticeably thicken and produce more mucus, clogging the gaps.

In COPD, there is often a cough with sputum production without any other symptoms. If the coughing up mucus loses transparency, the patient’s condition begins to rapidly deteriorate.

Morning migraine

A very alarming bell is the appearance of an acute throbbing headache in the morning. It occurs literally as soon as a person gets out of bed. This syndrome is explained simply: when the patient is in a horizontal position for a long time and breathes shallowly, the body accumulates carbon dioxide, which leads to dilation of the blood vessels in the brain, which causes severe pain.

Migraines are often not associated with ongoing pathological changes in the bronchopulmonary system. They are treated as a separate symptomatic symptom. To get rid of severe morning migraines, you need to get rid of their main culprit - lack of oxygen.

Swelling of the ankle area

When the bronchopulmonary structure is damaged and there is no adequate treatment, heart failure develops, because the circulatory system also suffers from a lack of oxygen. The sad result is fluid retention in the body. Which leads to the appearance of edema of the lower extremities (in the area of ​​​​the ankles and feet).

With the development of lung pathology, the heart reduces the effort with which it pushes out blood. Which has the most negative effect on the functioning of the kidneys and liver. As a result, an accumulation of toxic toxins and waste occurs in the human body, which leads to intoxication of the entire body.

Problems with night rest

When a person is in a horizontal position, it becomes more difficult for the affected lungs to work, which negatively affects the quality of sleep. Patients often wake up due to coughing attacks, getting out of bed, they feel severe dizziness and headaches. In this case, you should immediately pay attention to the health of the pulmonary organs and undergo an examination.

Ideally, for your lungs to return to full normalcy, you should completely forget about the habit of smoking. But the condition of the lungs should be monitored in any case. And at the slightest suspicion of an emerging pathology, immediately consult a doctor.

Detailed solution part 1 (page) 6 on the world around us for 4th grade students, authors N.F. Vinogradova, G.S. Kalinova. 2017

• Gdz workbook on the world around us for grade 4 can be found

Human organism

Question. Name different natural objects. How do objects of living and inanimate nature differ?

Answer. Natural objects include the sun, air, water, stones, soil, plants, animals, and humans. All nature is divided into living and nonliving. Both living and non-living things are made up of objects. An object is a component of something, in our case nature, that has certain properties. Objects of living nature have properties that objects of inanimate nature do not have - growth, development, reproduction, metabolism, maintaining a constant composition, response to external and internal stimuli.

Let's discuss it together. Can a person be called an object of living nature (organism)? What characteristics of living organisms can be attributed to humans?

Answer. A person can fully be called an object of living nature. Humans, like all living organisms, have such properties as metabolism (absorption of some substances, their transformation, release of other substances), reproduction, inheritance of certain properties, growth, development, maintaining the constancy of the internal composition. A person is able to perceive light, sound, smells, touches, and respond to them. Man is capable of changing the surrounding nature under the influence of human thought.

Nervous system

Question. Look at the diagram “Nervous system” (p. 7). Read the signatures. What does the human nervous system consist of?

Answer. The human nervous system consists of the brain, spinal cord and nerves, which are found in every part of the human body. Nerves arise from the brain and spinal cord and travel to muscles and internal organs.

Let's discuss it together. Consider images of the human and animal brains. Is the conclusion “The most complex brain is in humans” true?

Answer. The human brain is by far the most complex compared to other animals. Firstly, it has the largest volume, which means that a person has much more opportunities to carry out complex processes, such as memory, speech, thinking, memorization. The figure clearly shows that the human brain has convolutions. This makes it even more complex, the total number of nerve cells increases, and therefore the ability to perform various actions increases.

Question. What protects the brain and spinal cord from damage?

Answer. The brain and spinal cord are protected by bones. The skull bones protect the brain from damage. The spinal cord protects the spine from damage. The spinal cord is located inside it in a special canal, which is called the spinal cord.

Along with the brain and spinal cord, the bones of the skull and spine grow.

Question. Prepare a story on the topic “The importance of the nervous system for the body.” Note the coordinated work of the organs.

Answer. All healthy organs of our body act in concert and never make mistakes. All this happens thanks to the nervous system. The nervous system consists of sections that are interconnected. In general, if we consider the nervous system, it looks like a “net” in which all parts of our body are immersed. Thanks to this, whatever happens in one part of our body “becomes known” to other parts of our body. Nerves connect internal organs, muscles, and the skeletal system.

Thanks to the nervous system, we perceive information from the environment and information that comes from internal organs. In the brain, information is processed in special centers - visual, auditory and others. From there, signals go to the muscles that perform certain work. Signals also travel to the spinal cord.

The spinal cord is of great importance - it controls movements and is responsible for the coordinated functioning of internal organs. Therefore, when we run, our breathing quickens, our heartbeat quickens, and our blood vessels dilate. When we think intensely, the blood vessels that carry blood to the brain dilate. Thus, the nervous system allows all organs to work harmoniously, as a single mechanism.

Propulsion system

Let's discuss it together. If the human body had no bones, it would look like a rag doll. Is this statement true? Justify your opinions. Let's compare the answers with the text.

Answer. This statement is true. Human bones are connected to each other and form the so-called skeleton. The skeleton is the collection of all the bones of the human body. Thanks to them, the human body maintains a certain position in space and holds it. No wonder it is called the support of the body. Muscles are attached to the bones of the skeleton. Muscles and skeleton give the body a certain shape. Bones and muscles make up the musculoskeletal system.

Question. Tell us what makes up the human musculoskeletal system. What work (function) does it perform?

Answer. The human musculoskeletal system consists of the skeleton and muscles. It got its name from two words - support and movement. The support is made up of the skeleton - the totality of all human bones. There are more than 200 bones in the human body. The human skeleton functions as a support for the body, protects internal organs, and muscles are attached to it. Muscles are the basis of the motor system. In total, there are about 600 muscles in the human body. They perform the functions of moving and performing some kind of work. Controls the functioning of the muscles of the brain and spinal cord. Several muscles are involved in each work and thanks to the nervous system, the muscles work in concert.

Question. Muscles are compared to an elastic rubber band. How do you think why?

Answer. Muscles are like elastic bands because they have properties such as contraction and relaxation. These actions are performed alternately, which is why they are similar to an elastic band that can stretch and contract. It should be noted that muscles are often longer than wide.

Let's discuss it together. Let's compare the two drawings. Which activity is better for your muscles? Why? Let's compare the answers with the text.

Answer. In order for a person’s muscles to be strong and able to perform various jobs, they must be constantly trained. Activities such as skiing and walking up stairs keep your muscles strong. And such an activity as playing on the computer while lying on the bed makes the muscles flabby and weak.

This happens because during physical exercise, a large amount of oxygen and nutrients are supplied to the muscles, which allows the muscles to develop.

Question. Have your say. The girls argued. One is sure that it is better to carry the load in the right hand, but you just need to give it a rest. And the other insisted that the load must be carried by changing hands - now in the right, now in the left. Which girl is right and why?

Answer. It is better to carry the load alternately in the right and left hands. This contributes to the correct formation of posture, uniform distribution of the load on the left and right hands, due to which both the left and right hands will develop equally.

And if you carry a load only in your right hand, then it will be slightly larger than your left, and curvature of the spine and poor posture will also occur.

Question. Look at the pictures. Tell us what improves a person’s posture and what worsens it.

Answer. According to the drawings, physical education and sports, sports and ballroom dancing improve posture; posture is worsened by incorrect working posture at the table when doing written work, and improper carrying of heavy objects, for example, a heavy briefcase with school supplies. You cannot carry a heavy briefcase in one hand.

Question. Guess what the facial expressions of these children say.

Answer. Children's facial expressions indicate the following:

2. Joy

4. Surprise

Digestive system

Question. Why should a person constantly eat? Explain the importance of vitamins for humans. Explain the importance of vitamins for humans. (You already know that the word “vitamin” comes from the Latin word “vita”, which means “life”).

Answer. Food for humans is a necessary condition for life. Food contains nutrients. These include proteins, fats, carbohydrates, vitamins, and mineral salts. Nutrients are necessary building materials for human muscles and organs and provide the body with energy. With food comes water and minerals involved in metabolism.

Vitamins enter the body in small quantities, but they are very important. Vitamins influence the processes of growth and development of the body, regulate metabolism, ensure the processes of vision, wound healing, and the formation of the skeleton and muscles. With a lack of vitamins, the disease “vitaminosis” occurs. Such manifestations of vitamin deficiency as scurvy, rickets, night blindness and others are known.

Question. Explain the meaning of the proverb: “He who chews longer lives longer.”

Answer. The transformation of food begins in the oral cavity. It is crushed with the help of teeth. At this time, food is wetted with saliva. Thanks to this, food is easier to swallow, digested faster and absorbed better. Saliva also contains disinfectants and neutralizes pathogens. And if you swallow poorly chewed food, a large number of harmful microbes can enter the body. Also, under the influence of saliva, food begins to be digested in the oral cavity and arrives in the stomach prepared for further processing. All this affects human health, and ultimately, life expectancy.

Question. Explain which of these children will have healthy teeth.

Answer. A boy who regularly brushes his teeth will have healthy teeth. A boy who cracks walnuts and a girl who eats a lot of sweets will have weak teeth, as the enamel on their teeth will be destroyed.

Question. Why does Anton often have toothache?

Choose the correct answer and justify your opinion.

He brushes his teeth twice a day.

He chews gum all the time.

He eats a lot of sweets and chews nuts.

Answer. He eats a lot of sweets and chews nuts. As a result, the enamel on the teeth is destroyed and the infection penetrates into the hard tissues of the tooth.

Respiratory system

Exercise. Place your hand on your chest and count the number of inhalations and exhalations per minute while sitting and after 10 squats. What can be concluded?

Answer. For physical exercise, more energy is needed, which means more oxygen to the muscles, blood must move faster, so the heart begins to contract more often.

Exercise. Look at the drawing diagram. Trace the movement of air from the nasal cavity to the lungs when inhaling.

Answer. The respiratory organs are a group of organs that carry out gas exchange between the body and the environment. When you inhale, air enters the nasal cavity, then it moves to the larynx, trachea, then to the bronchi and lungs. When exhaling, the movement of air occurs in the reverse order: lungs, bronchi, trachea and nasal cavity.

Take care of your respiratory system

Question. Based on the pictures on p. 23, formulate the rules for caring for the respiratory system. Tips on p. 23-24.

1. Breathing should be even and measured

2. You need to breathe through your nose

3. You need to do physical exercise and sports.

4. It’s good to be in the fresh air

5. When coughing or sneezing, you must cover your mouth.

6. Regular wet cleaning of premises

7. Good posture is important for proper breathing.

8. When communicating with people who have an infectious disease, you must wear a gauze bandage and regularly ventilate the room.

Question. Prepare a story about the path the air takes during inhalation and exhalation.

Answer. During inhalation, air passes through the nasal cavity, larynx, trachea, bronchi and enters the lungs, and when exhaling, air movement occurs in the opposite direction.

Question. Explain why you should breathe through your nose.

Answer. Because, passing through the nose, the air is moistened, warmed in cold weather and cooled in hot weather, dust particles and microparticles from the air are retained in the nose, protecting the bronchi and lungs from them, and nasal mucus retains bacteria. Therefore, people who sit on vasoconstrictor drops or breathe through their mouths get sick more often.

Circulatory system

Let's discuss it together. Why is the circulatory system called the transport system?

Answer. This is a transport, or distribution, system through which cells and organs are supplied with oxygen and nutrients to ensure active life. This transport system works in two directions - with its help the body is also freed from metabolic products, toxins, and dead cells.

And the better the condition of the circulatory system, the better the channels, the less clogged they are, the better the metabolism, and the better the general condition of the body.

Question. What is a biological cell?

Answer. The cell is one of the main building, working and reproducing elements of living nature; it is an elementary living system. Plants and animal fungi are made up of cells. A person also consists of cells.

Question. Look at the diagram “Circulatory System” on p. 25. Follow the movement of blood in the body. Explain why the heart is compared to a pump.

Answer. The heart is compared to a pump, because the speed at which blood moves through the body and pressure depend on its operation. The heart has muscular walls and when it contracts, blood is released into the blood vessels. The heart beats about 100,000 times per day. Throughout life, the heart works and pumps tons of blood. That's why it's called a "pump".

Question. Make a plan to answer the question: “What is the importance of blood for the body?”

1. How much blood is in the human body

2. What work do different blood cells do?

3. What does blood carry?

Question. It is known that the size of a fist corresponds to the size of a person’s heart. Compare the heart sizes of yours and your mother's.

Answer. Mom has a bigger heart because her body grows until she’s 20, and I’m still 10.

How the body removes liquid substances it does not need

Question. Look at the drawing diagram. Read the text. Name the excretory organs, answer the question: “What is the significance of the excretory system?”

Answer. With the help of the excretory organs, the body gets rid of unnecessary substances. The main organ of excretion is the kidneys. A person has two of them. They are red-brown in color and shaped like beans. The kidneys are located on either side of the spine at lumbar level. From the kidneys there are two tubes - the ureters, which connect the kidneys to the bladder.

In the kidneys, the blood is filtered, getting rid of excess water and harmful substances. The kidneys produce urine, which is subsequently eliminated

Question. When examining a patient, a urine test is performed. Why do you think?

Answer. A urine test is done to determine from the chemical composition of urine what processes are occurring in our body. This is how the content of carbohydrates and proteins is determined. And other substances. The presence of blood cells is examined. All this helps to make a diagnosis of the disease.

Question. Prepare for a conversation about the excretory organs. Express your opinion: can the lungs be classified as excretory organs?

Answer. The urinary system plays an important role in the processes of excretion of metabolic products. It consists of paired kidneys, ureters, and a bladder, which opens to the outside through the urethra. The human excretory organs begin with the kidneys. These are paired bean-shaped organs. They are located in the abdominal cavity on both sides of the spine, towards which they are turned with the concave side. The excretory organs, in particular the kidney, consist of elementary structural units. It is in them that metabolic processes occur at the cellular level. Each kidney consists of a million nephrons - structural and functional units.

The lungs can conditionally be classified as excretory organs, since carbon dioxide and water are released when exhaling.

Leather

Question. Confirm or refute the statement: “With the help of the skin, our body senses changes in the external environment. We feel heat, cold, pain. That’s why we dress warmer when it’s cold, avoid sharp objects and other dangers, and harden our body.”

Answer. I can confirm this statement, since there are special sensitive cells in the skin. They each perform a specific job (function). They perceive external information - touch, temperature, pain. From them, the message goes to the brain, which processes signals and gives commands to the body. If it's cold, the muscles contract and we shiver, if it's hot, we sweat, etc.

Question. Express your opinion: why is the skin temperature different in different parts of the body? For example, under the arm it is 36.3-36.9 degrees, on the stomach - 34, and on the face - 20-25 degrees.

Answer. The temperature in different areas of the skin is different, the further from hot organs (heart, liver, large arteries) the lower the temperature, and also because the skin gives off heat to the environment. The skin on the face is not protected by anything, so the temperature is the lowest here, and under the arms the skin practically does not cool down.

Question. What rules do you need to know to avoid sun (heat) stroke?

Answer. To avoid sun (heat) stroke, you must follow the following rules:

1. It is necessary to avoid direct sunlight on the head, that is, you need to use a hat, preferably light colors, preferably white;

2. Clothes must be well breathable;

3. If a person is indoors, the room must be ventilated;

4. Physical work should be alternated with rest;

5. Sunbathing is necessary in moderation;

6. At the first signs of discomfort, immediately go to the shade and drink cool (but not ice-cold) water.

Question. Prepare a story on the topic “The importance of skin for the body” and complete practical tasks in the workbook.

Answer. Skin is of great importance to the human body. Firstly, it protects the body from external influences. Secondly, thanks to the skin, our body temperature is maintained - blood vessels expand or contract, sweat is released. Metabolic products are excreted with sweat. Vitamin D is formed in the skin under the influence of sunlight. Hair and nails are derivatives of the skin. Thanks to the skin, we perceive the world around us - touch, temperature, etc.

Focal formations in the lungs are tissue compaction caused by various diseases. They are usually detected by X-ray examination. Sometimes an examination by a specialist and diagnostic methods are not enough to make an accurate conclusion. For final confirmation, special examination methods must be carried out: blood tests, sputum tests, etc. This happens with malignant tumors, pneumonia and impaired fluid exchange in the respiratory system.

A lesion is a small, round or irregularly shaped spot that is visible on X-rays and is located in the lung tissue. They are divided into several varieties: single, single (up to 6 pieces) and multiple.

There is a certain difference between the internationally established concept of focal formations and what is accepted in domestic medicine. Abroad, these include compactions in the lungs measuring about 3 cm. Domestic medicine sets limits to 1 cm, and classifies other formations as infiltrates.

Computed tomography is more likely to determine the size and shape of the lung tissue compaction. This study also has a margin of error.

Focal formations in the respiratory organs are presented as degenerative changes in the tissues of the lungs or the accumulation of fluid in the form of sputum or blood. Many experts consider their establishment one of the important tasks.

Oncological factors

Up to 70% of single lesions in the lungs are malignant neoplasms. Using CT (computed tomography), and based on specific symptoms, a specialist can assume the occurrence of dangerous pathologies such as tuberculosis or lung cancer.

However, to confirm the diagnosis it is necessary to undergo the necessary tests. In some cases, a hardware examination is not enough to obtain a medical opinion. Modern medicine does not have a single algorithm for conducting research in all possible situations. The specialist considers each case separately.

The imperfection of the equipment does not allow a clear diagnosis of the disease using the hardware method. When taking an X-ray of the lungs, it is difficult to detect focal changes, the size of which does not reach 1 cm. Interposition of anatomical structures makes larger formations invisible.

The specialist offers patients to undergo examination using computed tomography. It allows you to view fabrics from any angle.

Computed tomography to diagnose the location of the lesion

Causes of focal formations in the lungs

The main factors of pathology include the occurrence of compactions on the lungs. Such symptoms are inherent in dangerous conditions that, in the absence of proper treatment, can cause death. Diseases that provoke this condition include:

• oncological diseases, the consequences of their development (metastases, neoplasms themselves, etc.);
• focal tuberculosis;
• pneumonia;
• caused by poor circulation or as a result of an allergic reaction;
• myocardial infarction;
• bleeding;
• severe bruises to the chest;

Most often, compactions occur due to inflammatory processes (acute pneumonia, pulmonary tuberculosis) or cancer.

A third of patients have minor signs of respiratory damage. A feature of pulmonary tuberculosis is the absence of symptoms or their minimal manifestation. It is mainly detected during preventive examinations. The main picture of tuberculosis is given by chest radiography, but it differs depending on the phase and duration of the process.

Basic diagnostic methods

To determine focal changes, it is necessary to undergo a special examination (radiography, fluorography or computed tomography). These diagnostic methods have their own characteristics.

When undergoing an examination in the form of fluorography, it is impossible to detect a compaction smaller than 1 cm in size. It will not be possible to analyze the entire picture completely and without errors.

Many doctors advise their patients to undergo a CT scan. This is a way to study the human body, allowing us to identify various changes and pathologies in the patient’s internal organs. It is one of the most modern and accurate diagnostic methods. The essence of the method is the influence of X-rays on the patient’s body, and then, after passing through it, computer analysis.

With its help you can install:

• in the shortest possible time and with particular accuracy, the pathology that affected the patient’s lungs;
• accurately determine the stage of the disease (tuberculosis);
• correctly establish the condition of the lungs (determine tissue density, diagnose the condition of the alveoli and measure tidal volume);
• analyze the condition of the pulmonary vessels of the lungs, heart, pulmonary artery, aorta, trachea, bronchi and lymph nodes located in the chest area.

This method also has weaknesses. Even with CT examination, focal changes are missed. This is explained by the low sensitivity of the device for lesions up to 0.5 cm in size and low tissue density.

Experts have found that with initial CT screening, the probability of not detecting pathological disorders in the form of focal formations is possible with its size of 5 mm in 50% of cases. When the diameter is 1 cm, the sensitivity of the device in this case is 95%.

The conclusion indicates the likelihood of developing a particular pathology. The location of the lesions on the lungs is not given decisive importance. Particular attention is paid to their contours. If they are uneven and unclear, with a diameter of more than 1 cm, then this indicates the occurrence of a malignant process. In the case of diagnosing clear edges of focal changes, we can talk about the development of benign neoplasms or tuberculosis.

During the examination, pay attention to the density of the tissues. Thanks to this sign, a specialist is able to distinguish pneumonia from changes caused by tuberculosis.

Another nuance of computed tomography is the determination of the substance collecting in the lungs. Only fat deposits make it possible to determine pathological processes, and the rest cannot be classified as specific symptoms.

After obtaining CT images of the lungs, in which the compactions are visible, they are classified. Modern medicine distinguishes the following types of them, according to size:

• small, components in diameter from 1 to 2 mm;
• medium – size in diameter 3-5 mm;
• large, components from 1 cm.

Focal formations in the lungs are usually classified by density:

• dense;
• medium density;
• loose.

Classification by quantity:

Single seals. They may be a factor in a serious pathology (malignant tumor) or refer to normal age-related changes that do not pose a threat to the patient’s life.

Multiple seals. They are mainly characteristic of pneumonia and tuberculosis, but sometimes numerous and quite rarely diagnosed cancers are also caused by the development of a large number of compactions.

In humans, the lungs are covered with a thin film called pleura. Seals in relation to it are:

• pleural lesions;
• subpleural lesions.

Modern medicine has several methods for diagnosing tuberculosis and other lung diseases. Computed tomography is widely used to identify subpleural lesions, while fluorography and radiography are not completely effective ways to determine the patient’s condition. They are located under the pleura, their location is characteristic of tuberculosis and cancer. Only this diagnostic method allows you to correctly determine the disease that has arisen.

Conclusion

Focal changes are caused not only by diseases that are easily treatable (pneumonia), but sometimes by more serious pathologies - tuberculosis, malignant or benign neoplasms. Modern diagnostic methods will help to detect them in a timely manner and prescribe correct and safe therapy.