Breathing regulation The concept of breathing in qigong, as well as in the ancient systems of daoin, is related to the concept of qi. In some cases, these are complete synonyms ("saturate the body with heavenly qi"), in others - complementary factors. Various types breathing create different Qi circulation in

Humoral physiopathology and hydrotherapy (hydrotherapy) Among the substances that form the structure of a living organism, the predominant part is represented by water containing minerals. So, in the brain, water is 77%, if we take into account the brain together with the brain

Humoral regulation of the activity of the heart The work of the heart is primarily influenced by the mediators acetylcholine, which is released in the endings of the parasympathetic nerves, it inhibits the activity of the heart, as well as adrenaline and norepinephrine, which are mediators of sympathetic nerves

Humoral regulation of vascular tone Humoral regulation of the vascular lumen is carried out due to chemical substances dissolved in the blood, which include hormones of general action, local hormones, mediators and metabolic products. They can be divided into two

Humoral regulation of lymph flow and lymph formation Adrenaline - increases the flow of lymph along lymphatic vessels mesentery and increases pressure in the chest cavity. Histamine - enhances lymph formation by increasing the permeability of blood capillaries, stimulates

Humoral regulation of respiration The main physiological stimulus of the respiratory centers is carbon dioxide. The regulation of respiration determines the maintenance of a normal CO2 content in the alveolar air and arterial blood. An increase in the CO2 content in

Regulation of salivation oral cavity irritation of the mechano-, thermo- and chemoreceptors of the mucous membrane occurs. Excitation from these receptors along the sensory fibers of the lingual (branch of the trigeminal nerve) and glossopharyngeal nerves,

The act of defecation and its regulation Fecal masses are removed using the act of defecation, which is a complex reflex process of emptying the distal colon through the anus. When filling the ampoule of the rectum with feces and increasing the pressure in it to 40 - 50 cm

Humoral The leading role in the regulation of kidney activity belongs to the humoral system. The function of the kidneys is influenced by many hormones, the main of which are antidiuretic hormone (ADH), or vasopressin, and aldosterone. Antidiuretic hormone (ADH), or

Humoral regulation of pain Mediators: acetylcholine, adrenaline, norepinephrine, serotonin activate chemonocyceptors. Acetylcholine causes burning pain when injected subcutaneously or when pricked into the mucous membrane. This pain usually lasts 15 - 45 minutes and can be

Plan:

1. Humoral regulation

2. The hypothalamic-pituitary system as the main mechanism of neuro-humoral regulation of hormone secretion.

3. Hormones of the pituitary gland

4. Thyroid hormones

5. Hormones parathyroid glands

6. Pancreatic hormones

7. The role of hormones in the adaptation of the body under the influence of stress factors

Humoral regulation- This is a kind of biological regulation in which information is transmitted using biologically active substances that are carried throughout the body by blood, lymph, intercellular fluid.

Humoral regulation differs from nervous one:

information carrier - a chemical substance (with a nervous one - a nerve impulse, PD);

the transmission of information is carried out by the flow of blood, lymph, by diffusion (in the case of a nervous one - by nerve fibers);

the humoral signal propagates more slowly (with blood flow in the capillaries - 0.05 mm / s) than the nervous one (up to 120-130 m / s);

the humoral signal does not have such a precise "addressee" (the nervous one is very specific and precise), the effect on those organs that have receptors for the hormone.

Humoral regulation factors:

"Classic" hormones

Hormones APUD system

Classic hormones proper are substances synthesized by the endocrine glands. These are hormones of the pituitary gland, hypothalamus, pineal gland, adrenal glands; pancreas, thyroid, parathyroid, thymus, gonads, placenta (Fig. I).

In addition to the endocrine glands, in various tissues and tissues there are specialized cells that bluish substances that act on target cells by diffusion, that is, entering the bloodstream, locally. These are paracrine hormones.

These include neurons of the hypothalamus, which produce some hormones and neuropeptides, as well as cells of the APUD system, or systems for the capture of amine precursors and their decarboxylation. An example is: liberins, statins, hypothalamic neuropeptides; interstitial hormones, components of the renin-angiotensin system.

2) Tissue hormones are secreted by non-specialized cells of various types: prostaglandins, enkephalins, components of the kallikreinininin system, histamine, serotonin.

3) Metabolic factors- these are nonspecific products that are formed in all cells of the body: lactic acid, pyruvic acid, CO2, adenosine, etc., as well as decay products during intense metabolism: increased content of K +, Ca 2+, Na +, etc.

The functional significance of hormones:

1) ensuring growth, physical, sexual, intellectual development;

2) participation in the adaptation of the organism in various changing conditions of the external and internal environment;

3) maintaining homeostasis.

Rice. 1 Endocrine glands and their hormones

Properties of hormones:

1) the specificity of the action;

2) the distant nature of the action;

3) high biological activity.

1. The specificity of the action is ensured by the fact that hormones interact with specific receptors located in certain target organs. As a result, each hormone acts only on specific physiological systems or organs.

2. The distance lies in the fact that the target organs, which are affected by hormones, as a rule, are located far from the place of their formation in the endocrine glands. Unlike "classical" hormones, tissue hormones act paracrine, that is, locally, not far from the place of their formation.

Hormones act in very small quantities, in which they are manifested high biological activity... So, the daily requirement for an adult is: thyroid hormones - 0.3 mg, insulin - 1.5 mg, androgens - 5 mg, estrogens - 0.25 mg, etc.

The mechanism of action of hormones depends on their structure

Hormones of the protein structure Hormones of the steroid structure

Rice. 2 Mechanism of hormonal control

Hormones of the protein structure (Fig. 2) interact with the receptors of the plasma membrane of the cell, which are glycoproteins, and the specificity of the receptor is due to the carbohydrate component. The result of the interaction is the activation of protein phosphokinases, which provide

phosphorylation of regulatory proteins, transfer of phosphate groups from ATP to hydroxyl groups of serine, threonine, tyrosine, protein. The final effect of the action of these hormones can be - a reduction, an increase in enzymatic processes, for example, glycogenolysis, an increase in protein synthesis, an increase in secretion, etc.

The signal from the receptor with which the protein hormone interacted is transmitted to the protein kinase with the participation of a specific mediator or secondary messenger. Such messengers can be (Fig.H):

1) cAMP;

2) ions Ca 2+;

3) diacylglycerol and inositol triphosphate;

4) other factors.

Figure H. The mechanism of membrane reception of hormonal signal transmission in the cell with the participation of secondary mediators.

Hormones of the steroid structure (Fig. 2) easily penetrate into the cell through the plasma membrane due to their lipophilicity and interact in the cytosol with specific receptors, forming a “hormone-receptor” complex that moves into the nucleus. In the nucleus, the complex breaks down and hormones interact with nuclear chromatin. As a result of this, interaction with DNA occurs, and then the induction of messenger RNA. Due to the activation of transcription and translation after 2-3 hours, after exposure to the steroid, an increased synthesis of induced proteins is observed. In one cell, a steroid affects the synthesis of no more than 5-7 proteins. It is also known that in the same cell a steroid hormone can induce the synthesis of one protein and repression of the synthesis of another protein (Fig. 4).

The action of thyroid hormones is carried out through the receptors of the cytoplasm and the nucleus, as a result of which the synthesis of 10-12 proteins is induced.

Reflation of hormone secretion is carried out by the following mechanisms:

1) the direct effect of the concentrations of blood substrates on the cells of the gland;

2) nervous regulation;

3) humoral regulation;

4) neurohumoral regulation (hypothalamic-pituitary system).

In the regulation of the endocrine system, an important role is played by the principle of self-regulation, which is carried out by the type of feedback. Distinguish between positive (for example, an increase in blood sugar leads to an increase in insulin secretion) and negative feedback (with an increase in the level of thyroid hormones in the blood, the production of thyroid-stimulating hormone and thyroliberin, which provide the release of thyroid hormones, decreases).

So, the direct influence of the concentrations of blood substrates on the cells of the gland follows the principle of feedback. If the level of a substance in the blood changes, which is controlled by a specific hormone, then “a tear responds with an increase or decrease in the secretion of this hormone.

Nervous regulation is carried out due to the direct influence of the sympathetic and parasympathetic nerves on the synthesis and secretion of hormones of the neurohypophysis, the adrenal medulla), as well as indirectly, “by changing the intensity of the blood supply to the gland. Emotional, psychological influences through the structures of the limbic system, through the hypothalamus - can significantly affect the production of hormones.

Hormonal regulation It is also carried out according to the principle of feedback: if the level of the hormone in the blood rises, then in the agvet, the release of those hormones that control the content of this hormone decreases, which leads to a decrease in its concentration in the crocus.

For example, with an increase in the level of cortisone in the blood, the release of ACTH (a hormone that stimulates the secretion of hydrocortisone) decreases, and as a result

Decrease in its level in the blood. Another example of hormonal regulation can be this: melatonin (a hormone of the pineal gland) modulates the function of the adrenal glands, thyroid gland, gonads, i.e. a certain hormone can affect the content of other hormonal factors in the blood.

The hypothalamic-pituitary system as the main mechanism of neuro-humoral regulation of hormone secretion.

The function of the thyroid, gonads, adrenal cortex is regulated by the hormones of the anterior pituitary gland - the adenohypophysis. Here are synthesized tropic hormones: adrenocorticotropic (ACTH), thyroid-stimulating (TSH), follicle-stimulating (FS) and luteinizing (LH) (Fig. 5).

With some convention, somatotropic hormone (growth hormone) also refers to triple hormones, which exerts its influence on growth not only directly, but also indirectly through hormones - somatomedins, which are formed in the liver. All these tropic hormones are so named due to the fact that they provide the secretion and synthesis of the corresponding hormones of other endocrine glands: ACTH -

glucocorticoids and mineralocorticoids: TSH - thyroid hormones; gonadotropic - sex hormones. In addition, interludes (melanocyte-stimulating hormone, MCH) and prolactin are formed in the adenohypophysis, which have an effect on peripheral organs.

Rice. 5. Regulation of the endocrine glands of the central nervous system. TL, SL, PL, GL and CL - respectively, thyreoliberin, somatoliberin, prolactoliberin, gonadoliberin and corticoliberin. SS and PS - somatostatin and prolactostatin. TSH - thyroid-stimulating hormone, STH - somatotropic hormone (growth hormone), Pr - prolactin, FSH - follicle-stimulating hormone, LH - luteinizing hormone, ACTH - adrenocorticotropic hormone

Thyroxine Triiodothyronine Androgens Glucorticoids

Estrogens

In turn, the release of all 7 of these hormones of the adenohypophysis depends on the hormonal activity of neurons in the pituitary zone of the hypothalamus - mainly by the paraventricular nucleus (PVN). Here hormones are formed that have a stimulating or inhibitory effect on the secretion of hormones from the adenohypophysis. Stimulants are called releasing hormones (liberins), inhibitors are called statins. Thyreoliberin, gonadoliberin are isolated. somatostatin, somatoliberin, prolactostatin, prolactoliberin, melanostatin, melanoliberin, corticoliberin.

Releasing hormones are released from the processes of the nerve cells of the paraventricular nucleus, enter the portal venous system of the hypothalamic-pituitary gland and are delivered with blood to the adenohypophysis.

The regulation of the hormonal activity of most endocrine glands is carried out according to the principle of negative feedback: the hormone itself, its amount in the blood, regulates its formation. This effect is mediated through the formation of the corresponding releasing hormones (Fig. 6.7)

In the hypothalamus (supraoptic nucleus), in addition to releasing hormones, vasopressin (antidiuretic hormone, ADH) and oxytocin are synthesized. Which are transported in the form of granules along nerve processes in the neurohypophysis. The release of hormones by neuroendocrine cells into the bloodstream is due to reflex nerve stimulation.

Rice. 7 Straight and feedbacks in the neuroendocrine system.

1 - slowly developing and long-term inhibition of the secretion of hormones and neurotransmitters , as well as behavior change and memory formation;

2 - rapidly developing but prolonged inhibition;

3 - short-term inhibition

Pituitary hormones

In the posterior lobe of the pituitary gland - the neurohypophysis - are oxytocin and vasopressin (ADH). ADH affects three types of cells:

1) cells renal tubules;

2) smooth muscle cells of blood vessels;

3) liver cells.

In the kidneys, it promotes the reabsorption of water, which means its preservation in the body, a decrease in urine output (hence the name antidiuretic), in the blood vessels it causes contraction of smooth muscles, narrowing their radius, and as a result - increases blood pressure (hence the name "vasopressin"), in liver - stimulates gluconeogenesis and glycogenolysis. In addition, vasopressin has an antinociceptive effect. ADH is intended to regulate the osmotic pressure of the blood. Its secretion increases under the influence of such factors: an increase in blood osmolarity, hypokalemia, hypocalcemia, an increase in a decrease in BCC, a decrease in blood pressure, increased body temperature, activation of the sympathetic system.

With insufficient excretion of ADH, diabetes insipidus develops: the volume of excreted urine per day can reach 20 liters.

Oxytocin in women plays the role of a regulator of uterine activity and is involved in lactation processes as an activator of myoepithelial cells. The increase in oxytocin production occurs during cervical dilatation at the end of pregnancy, ensuring its contraction during labor, as well as during breastfeeding, ensuring the secretion of milk.

In the anterior lobe of the pituitary gland, or adenohypophysis, thyroid-stimulating hormone (TSH), growth hormone (STH) or growth hormone are produced, gonadotropic hormones, adrenocorticotropic hormone (ACTH), prolactin, and in the middle proportion - melanocyte-stimulating hormone (MSH) or interludes.

A growth hormone stimulates protein synthesis in bones, cartilage, muscles and liver. In an immature organism, it provides growth in length by increasing the proliferative and synthetic activity of cartilage cells, especially in the growth zone of long tubular bones while stimulating the growth of the heart, lungs, liver, kidneys and other organs in them. In adults, it controls the growth of organs and tissues. STH reduces the effects of insulin. Its release into the blood increases during deep sleep, after muscle exertion, with hypoglycemia.

The growth effect of growth hormone is mediated by the effect of the hormone on the liver, where somatomedins (A, B, C) or growth factors are formed, which cause the activation of protein synthesis in cells. The value of STH is especially great during the growth period (prepubertal, pubertal periods).

During this period, GH agonists are sex hormones, an increase in the secretion of which contributes to a sharp acceleration of bone growth. However, long-term formation of large amounts of sex hormones leads to the opposite effect - to the cessation of growth. Not enough GH leads to dwarfism (nanism), and too much GH leads to gigantism. Some adult bones may resume growth if excessive secretion STG. Then the proliferation of cells of the growth zones resumes. Which leads to overgrowth

In addition, glucocorticoids inhibit all components inflammatory response- reduce capillary permeability, inhibit exudation, reduce the intensity of phagocytosis.

Glucocorticoids sharply reduce the production of lymphocytes, reduce the activity of T-killers, the intensity of immunological surveillance, hypersensitivity and sensitization of the body. All this allows us to consider glucocorticoids as active immunosuppressants. This property is used in the clinic to arrest autoimmune processes, to reduce immune defense host organism.

Glucocorticoids increase sensitivity to catecholamines, increase the secretion of hydrochloric acid and pepsin. An excess of these hormones causes bone demineralization, osteoporosis, loss of Ca 2+ in the urine, and reduces the absorption of Ca 2+. Glucocorticoids affect the function of VND - they increase the activity of information processing, improve the perception of external signals.

Mineralocorticoids(aldosgerone, deoxycorticosterone) are involved in the regulation mineral metabolism... The mechanism of action of aldosterone is associated with the activation of protein synthesis involved in the reabsorption of Na + - Na +, K h -ATPase. By increasing reabsorption and decreasing it for K + in the distal tubules of the kidney, salivary and gonads, aldosterone promotes the retention of NO and CG in the body and the elimination of K + and H from the body. Thus, aldosterone is a sodium-sparing hormone, as well as a potassium uretic hormone. delay IA \ and after it and water, it contributes to an increase in the BCC and, as a consequence, an increase in blood pressure.In contrast to glucocorticoids, mineralocorticoids contribute to the development of inflammation, because increase capillary permeability.

Sex hormones the adrenal glands perform the function of the development of the genital organs and the appearance of secondary sexual characteristics during the period when the sex glands are not yet developed, that is, in childhood also in old age.

Hormones of the adrenal medulla - adrenaline (80%) and norepinephrine (20%) - cause effects that are largely identical to the activation of the nervous system. Their action is realized through interaction with a- and (3-adrenergic receptors. Therefore, they are characterized by activation of the heart, vasoconstriction of the skin, expansion of the bronchi, etc. Adrenaline affects carbohydrate and fat metabolism, increasing glycogenolysis and lipolysis.

Catecholamines are involved in the activation of thermogenesis, in the regulation of the secretion of many hormones - they increase the release of glucagon, renin, gastrin, parathyroid hormone, calcitonin, thyroid hormones; reduce insulin release. Under the influence of these hormones, the performance of skeletal muscles and the excitability of receptors increase.

With hyperfunction of the adrenal cortex in patients, secondary sexual characteristics change noticeably (for example, women may have male sexual characteristics - a beard, mustache, voice timbre). Obesity (especially in the area, face, trunk), hyperglycemia, water and sodium retention in the body, etc. are observed.

Hypofunction of the adrenal cortex causes Addison's disease - a bronze tint of the skin (especially of the face, neck, hands), loss of appetite, vomiting, hypersensitivity to cold and pain, high susceptibility to infections, increased urine output (up to 10 liters of urine per day), thirst, decreased performance.

The most difficult questions of teaching the section "Man and his health"

The proposed course involves the study of the most complex issues of the section "Man and his health", affecting the physiological mechanisms of the functioning of the human body as a whole and its individual structures (cells, tissues, organs).

The purpose of the course is to give the teacher modern knowledge about the laws of the functioning of the human body, to show their role and place in the educational process in accordance with educational standards, USE materials, new generation biology textbooks. The content of the course is not only theoretical, but also practice-oriented, expanding the possibilities of using the materials of the educational program for the introduction of new pedagogical technologies.

The main tasks solved during the study of the training course:

disclosure and deepening of the most complex anatomical and physiological concepts;
familiarization with educational standards, programs and existing textbooks for the section "Man and his health" and their analysis;
mastering the methodology for teaching complex issues of the section in the lesson and in extracurricular activities;
application of new educational technologies.

The integrated approach proposed by the authors provides ample opportunities for the use of almost all textbooks on this topic, approved by the Ministry of Education and Science of the Russian Federation. A significant role is assigned to the formation of pedagogical skills in designing the educational process, depending on the material and technical equipment of the office and the interests of schoolchildren.

The materials of the training course can be used in the lesson and in extracurricular activities, to prepare students for the exam, olympiads in biology and ecology. The novelty of this training course lies in its focus on modern forms organization of the pedagogical process, examples of which are given in all lectures.

Course curriculum

Lecture 1
Regulatory systems of the body

Currently, science has formed the idea that the main life processes of complex multicellular organisms, including humans, are supported by three regulatory systems: nervous, endocrine and immune.

Each multicellular organism develops from one cell - a fertilized egg (zygote). First, the zygote divides and forms cells similar to itself. Differentiation begins from a certain stage. As a result, trillions of cells are formed from the zygote, having different forms and functions, but making up a single, integral organism. A multicellular organism can exist as a whole thanks to the information contained in the genotype (a set of genes received by descendants from parents). The genotype is the basis of hereditary traits and developmental programs. Throughout an individual's life, the immune system provides control over the genetic constancy of the organism. Coordination of the activity of various organs and systems, as well as adaptation to changing environmental conditions are functions of the nervous and humoral systems.

Humoral regulation is phylogenetically the most ancient. It ensures the interconnection of cells and organs in primitive organisms that do not have a nervous system. The main regulatory substances in this case are metabolic products - metabolites. This method of regulation is called humoral-metabolic... It, like other types of humoral regulation, is based on the principle of “all-all-all”. Released substances are distributed throughout the body and change the activity of life support systems.

In the process of evolutionary development, a nervous system appears, and humoral regulation is increasingly subordinate to the nervous one. The nervous regulation of functions is more perfect. It is based on a letter-with-address alarm. Biologically important information reaches a specific organ via nerve fibers. The development of nervous regulation does not eliminate the more ancient - humoral. The nervous and humoral systems are combined into a neurohumoral system for the regulation of functions. In highly developed living organisms, a specialized system appears - the endocrine system. The endocrine system uses special chemicals called hormones to transmit signals from one cell to another. Hormones are biologically active substances that are carried with the bloodstream to various bodies and regulate their work. The action of hormones is manifested at the cell level. Some hormones (adrenaline, insulin, glucagon, pituitary hormones) bind to receptors on the surface of target cells, activate reactions in the cell, and change physiological processes... Other hormones (hormones of the adrenal cortex, sex hormones, thyroxine) penetrate into the cell nucleus, bind to a section of the DNA molecule, "turning on" certain genes. As a result, the formation of mRNA and the synthesis of proteins that alter the functions of the cell are "triggered". Hormones that penetrate into the nucleus launch the "programs" of the cells, therefore they are responsible for their general differentiation, the formation of sex differences, and many behavioral reactions.

The evolution of neurohumoral regulation of functions proceeded as follows.

Metabolic regulation - due to the products of intracellular metabolism (protozoa, sponges).
Nervous regulation - appears in coelenterates.
Neurohumoral regulation. Some invertebrates develop neurosecretory cells - nerve cells capable of producing biologically active substances.
Endocrine regulation. In arthropods and vertebrates, in addition to nervous and simple humoral (due to metabolites) regulation, endocrine regulation of functions is added.

The following functions of regulatory systems are distinguished.

Nervous system.

Regulation and coordination of all organs and systems, maintaining the constancy of the internal environment of the body (homeostasis), uniting the body into a single whole.
The relationship of the body with the environment and adaptation to changing environmental conditions (adaptation).

Endocrine system.

Physical, sexual and mental development.
Maintaining body functions at a constant level (homeostasis).
Adaptation of the body to changing environmental conditions (adaptation).

The immune system.

Control over the genetic constancy of the internal environment of the body.

The immune and neuroendocrine systems form a single information complex and communicate in the same chemical language. Many biologically active substances (for example, substances of the hypothalamus, pituitary hormones, endorphins, etc.) are synthesized not only in the hypothalamus and pituitary gland, but also in the cells of the immune system. Thanks to a single biochemical language, regulatory systems closely interact with each other. Thus, β-endorphin, released by lymphocytes, acts on pain receptors and reduces the feeling of pain. On immune cells there are receptors that interact with peptides of the hypothalamus and pituitary gland. Some substances secreted in the immune system (in particular, interferons) interact with specific receptors on the neurons of the hypothalamus, thereby regulating the release of pituitary hormones.

At the level of physiological reactions of the body, the interaction of regulatory systems is manifested during the development of stress. The consequences of stress are expressed in the disruption of the functions of regulatory systems and processes controlled by them. The action of stressors is perceived by the higher parts of the nervous system (cerebral cortex, diencephalon) and has two outputs, realized through the hypothalamus:

1) in the hypothalamus are the higher autonomic nerve centers that regulate through the sympathetic and parasympathetic divisions the activity of all internal organs;

2) the hypothalamus controls the work of the endocrine glands, which reduce the functional activity of the immune system, including the adrenal glands, which produce stress hormones.

The role of stress in development has now been proven ulcerative lesions gastric mucosa, hypertension, atherosclerosis, dysfunctions and structure of the heart, immunodeficiency states, malignant tumors and etc.

Possible outcomes of the stress response are shown in Scheme 1.

Scheme 1

To date, the connections between the nervous and endocrine systems, an example of which can be the hypothalamic-pituitary system, are well studied.

The pituitary gland, or inferior cerebral appendage, is located under the hypothalamus in a notch of the skull bones called the sella turcica, and connects to it through a special leg. The mass of the human pituitary gland is small, about 500 mg, the size is no more than an average cherry. The pituitary gland consists of three lobes - anterior, middle and posterior. The anterior and middle lobes are combined into the adenohypophysis, and the posterior lobe is otherwise called the neurohypophysis.

The activity of the adenohypophysis is under the direct control of the hypothalamus. In the hypothalamus, biologically active substances (hypothalamic hormones, releasing factors) are produced, which enter the pituitary gland with blood flow and stimulate or inhibit the formation of pituitary tropic hormones. Tropic hormones of the pituitary gland regulate the activity of other endocrine glands. These include: corticotropin, which regulates the secretory activity of the adrenal cortex; thyrotropin, which regulates the activity of the thyroid gland; lactotropin (prolactin), which stimulates the formation of milk in the mammary glands; somatotropin, which regulates growth processes; lutropin and follitropin, which stimulate the activity of the gonads; melanotropin, which regulates the activity of pigment-containing cells of the skin and retina.

The posterior lobe of the pituitary gland is connected with the hypothalamus by axonal connections, i.e. the axons of the neurosecretory cells of the hypothalamus end on the cells of the pituitary gland. Hormones synthesized in the hypothalamus are transported along axons to the pituitary gland, and from the pituitary gland they enter the bloodstream and are delivered to target organs. The hormones of the neurohypophysis are antidiuretic hormone (ADH), or vasopressin, and oxytocin. ADH regulates kidney function by concentrating urine and increases blood pressure. Oxytocin in large quantities is released into the blood in female body at the end of pregnancy, providing childbirth.

As mentioned above, most of the neuroendocrine regulatory responses provide homeostasis and adaptation of the body.

Homeostasis, or homeostasis (from homoios- similar and stasis- standing) - the dynamic balance of the body, supported by regulatory systems due to the constant renewal of structures, material-energy composition and state.

The doctrine of homeostasis was created by C. Bernard. Studying carbohydrate metabolism in animals, K. Bernard drew attention to the fact that the concentration of glucose in the blood (the most important source of energy for the body) fluctuates very slightly, within 0.1%. With an increase in glucose content, the body begins to "suffocate in the smoke" of under-oxidized carbohydrates, with a deficiency, an energy hunger arises. In both cases, there is a sharp weakness and clouding of consciousness. In this particular fact, C. Bernard saw a general pattern: the constancy of the internal environment is a condition for a free, independent life. The term "homeostasis" was introduced into science by W. Cannon. He understood by homeostasis the stability and consistency of all physiological processes.

Currently, the term "homeostasis" refers not only to the regulated parameters, but also to the mechanisms of regulation. Reactions that provide homeostasis can be directed to:

- maintaining a certain level of the stationary state of the organism or its systems;
- elimination or limitation of the action of harmful factors;
- changes in the relationship of the organism and changing environmental conditions.

The most tightly controlled homeostatic constants of the body include the ionic and acid-base composition of blood plasma, the content of glucose, oxygen, carbon dioxide in arterial blood, body temperature, etc. ...

The concept of "adaptation" (from adaptatio- adapt) has a general biological and physiological significance... From a general biological point of view, adaptation is a combination of morphophysiological, behavioral, population and other features of a given biological species, which provides the possibility of a specific lifestyle in certain environmental conditions.

How physiological concept adaptation means the process of adaptation of an organism to changing environmental conditions (natural, industrial, social). Adaptation is all types of adaptive activity at the cellular, organ, systemic and organismic levels. There are 2 types of adaptation: genotypic and phenotypic.

As a result genotypic adaptation based on hereditary variability, mutations and natural selection modern species animals and plants.

Phenotypic adaptation- a process that develops in the course of an individual's life, as a result of which the organism acquires a previously absent resistance to a certain environmental factor. There are two stages of phenotypic adaptation: an urgent stage (urgent adaptation) and a long-term stage (long-term adaptation).

Urgent adaptation arises immediately after the onset of the stimulus and is realized on the basis of ready-made, previously formed mechanisms. Long-term adaptation arises gradually, as a result of prolonged or repeated action on the body of this or that environmental factor. In fact, long-term adaptation develops on the basis of repeated implementation of urgent adaptation: there is a gradual accumulation of certain changes, and the body acquires a new quality and turns into an adapted one.

Examples of urgent and long-term adaptation

Adaptation to muscle activity. The running of an untrained person occurs at close to the limiting changes in heart rate, pulmonary ventilation, and maximum mobilization of the glycogen reserve in the liver. Wherein physical labor can be neither intense enough nor long enough. With long-term adaptation to physical activity as a result of training, skeletal muscle hypertrophy and an increase in the number of mitochondria in them by 1.5-2 times, an increase in the power of the circulatory and respiratory systems, an increase in the activity of respiratory enzymes, hypertrophy of neurons in the motor centers, etc. increase the intensity and duration of muscle activity.

Adaptation to hypoxic conditions. The ascent of an untrained person to the mountains is accompanied by an increase in the heart rate and minute volume of blood, the release of blood from blood depots, due to which there is an increase in oxygen delivery to organs and tissues. At the initial stages, there are no changes on the part of respiration, because in high-altitude conditions in the atmospheric air, the content of not only oxygen, but also carbon dioxide, which is the main stimulator of the activity of the respiratory center, is reduced. With long-term adaptation to a lack of oxygen, the sensitivity of the respiratory center to carbon dioxide increases, and pulmonary ventilation increases. This reduces the stress on the cardiovascular system. Increases the synthesis of hemoglobin and the formation of red blood cells in red bone marrow... The activity of respiratory enzymes in tissues increases. These changes make the body adapted to high altitude conditions. In people who have adapted well to a lack of oxygen, the content of erythrocytes in the blood (up to 9 million / μl), indicators of cardiovascular and respiratory systems, physical and mental performance do not differ from those of the highlanders.

The possibilities and limits of human adaptive reactions are determined by the genotype and are realized under the condition of the action of certain environmental factors. If the factor did not work, then the adaptation is not implemented. For example, an animal raised among humans does not adapt to its natural environment. If a person has led all his life sedentary image life, he will not be able to adapt to physical labor.

Examples of function regulation

Nervous regulation. An example of neural regulation is the regulation of blood pressure. In an adult, the blood pressure is maintained at a certain level: systolic - 105–120 mm Hg, diastolic - 60–80 mm. Hg After an increase in pressure caused different factors(for example, physical activity), at healthy person it quickly returns to normal due to signals from the cardiac nerve center of the medulla oblongata. The mechanism of this reaction is shown in Scheme 2.

Scheme 2

Humoral regulation. An example of humoral regulation is maintaining a certain level of glucose in the blood. Carbohydrates from food are broken down to glucose, which is absorbed into the blood. The glucose content in human blood is 60–120 mg% (after eating - 110–120 mg%, after moderate fasting - 60–70 mg%). Glucose is used as an energy source by all cells in the body. The release of glucose into most tissues is provided by the pancreatic hormone insulin. Nerve cells receive glucose independently of insulin due to the activity of glial cells, which regulates metabolism in neurons. If an excess amount of glucose enters the body, it is stored in the form of liver glycogen. With a lack of glucose in the blood, under the influence of the pancreatic hormone glucagon and the adrenal medulla hormone adrenaline, glycogen is broken down to glucose. If glycogen stores are depleted, then glucose can be synthesized from fats and proteins with the participation of adrenal cortex hormones - glucocorticoids. At low concentrations glucose in the blood (below 60 mg%), the production of insulin stops and glucose does not enter the tissue (it is saved for brain cells), and fats are used as an energy source. With very high concentrations glucose in the blood (over 150-180 mg%), which may be in people with patients diabetes mellitus, glucose is excreted in the urine. This phenomenon is called glucosuria. The mechanism of blood glucose regulation is shown in Scheme 3.

Scheme 3

1 - insulin
2 - glucagon

Neurohumoral regulation. Examples of neurohumoral regulation include regulation of energy (food) consumption and regulation deep temperature body.

Regulation of energy consumption.

Energy enters the body with food. According to the first law of thermodynamics, the amount of energy consumed = work performed + heat production + stored energy (fats and glycogen), i.e. the amount of chemical energy contained in food in an adult should be such as to cover the costs of the work performed (physical and mental labor) and the maintenance of body temperature.

If the amount of food consumed is more than necessary, then an increase in body weight occurs, if less, it decreases. Due to the fact that the reserves of carbohydrates in the body are limited by the capacity of the liver, the excess amount of consumed carbohydrates turns into fats and is stored in reserve in the subcutaneous fatty tissue. In childhood, some of the substances and energy are spent on growth processes.

Food intake is regulated by the nerve centers of the hypothalamus: the center of hunger and the center of satiety. With a lack nutrients the hunger center is activated in the blood, stimulating food-searching reactions. After a meal, saturation signals arrive at the saturation center, which inhibits the activity of the hunger center (Scheme 4).

Scheme 4

Signals to the saturation center can come from different receptors. These include mechanoreceptors of the stomach wall, which come into a state of excitement after eating; thermoreceptors, signals from which come as a result of an increase in temperature caused by a specific dynamic action of food (after a meal, especially protein, the level of metabolism increases and, accordingly, body temperature). There are theories that explain food consumption by chemical signals. In particular, the saturation center begins to send inhibitory signals to the hunger center after an increase in the content of glucose or fat-like substances in the blood.

Regulation of deep body temperature.

In warm-blooded (homeothermic) animals, the temperature of the "core" of the body is maintained at a constant level. The formation of heat in the body occurs due to exothermic reactions in every living cell. The amount of heat generated in the organ depends on the intensity of metabolism: in the liver - it is greatest, in the bones - the least. The return of heat occurs from the surface of the body due to physical processes: heat radiation, heat conduction and evaporation of liquid (sweat).

Through radiation, the body loses heat in the form of infrared rays. However, if the ambient temperature is higher than the body temperature, then infrared radiation from the environment will be absorbed by the body and its temperature may rise. If the body is in contact with cold bodies, good heat conductors, for example cold water, damp cold earth, stones, metals, etc., it loses heat by heat conduction. At the same time, the risk of hypothermia is high.

If the ambient temperature is higher than the body temperature, then perspiration is the only way to cool. High ambient temperatures and high humidity make it difficult for sweat to evaporate and increase the risk of overheating. An increase in heat generation can occur due to muscle work, tremors, and an increase in metabolic intensity.

Thermoregulation is controlled by the nervous and endocrine systems. The somatic part of the nervous system provides such reactions that prevent hypothermia, such as muscle work and tremors. Sympathetic department the autonomic nervous system controls the change in the lumen of blood vessels (when the temperature rises, they expand, when the temperature decreases, it narrows), perspiration, non-trembling thermogenesis (oxidation of free fatty acids in brown fat), contraction of smooth muscles that raise the hair.

When the ambient temperature drops, the activity of the thyroid and adrenal glands increases. The thyroid hormone thyroxine increases the intensity of redox reactions in cells. The adrenal medulla hormone adrenaline also increases metabolism.

Regulation involving the nervous, endocrine and immune systems. Sleep is an example of function regulation involving all regulatory systems. Today, there are three groups of theories explaining the nature of sleep: nervous, humoral and immune.

Nervous theories associate sleep with work nerve centers cerebral cortex, hypothalamus and reticular formation of the brain stem. The cortical theory of sleep was proposed by I.P. Pavlov, who showed in experiments on animals that during sleep inhibition occurs in the neurons of the cortex. Later, centers were discovered that regulate the alternation of sleep and wakefulness in the hypothalamus.

The reticular formation of the brain stem, collecting information from the body's receptor structures, maintains tone (the waking state of the cortex), i.e. also participates in the regulation of sleep – wakefulness processes. When the reticular formation is blocked by some substances, a dream-like state occurs.

Humoral factors some hormones regulate sleep. It has been shown that with the accumulation of the pineal gland hormone serotonin in the blood, favorable conditions are created for REM sleep, during which the processing of information received by a person during wakefulness occurs.

Immune theory sleep received experimental confirmation after checking long-known facts about increased sleepiness people sick infectious diseases... It turned out that the substance muramil-peptide, which is part of the bacterial cell wall, stimulates the formation of one of the cytokines that regulate sleep by the cells of the immune system. Administration of muramil peptide to animals caused excessive sleep in them.

Methodological support of the course

Educational standards, curricula and textbooks for the section "Man and his health"

Modern educational standards are approved by the order of the Ministry of Education of Russia No. 1089 dated March 5, 2004. According to the standard, the section "Man and his health" is studied in the 8th grade. However, in a number of schools the process of transition from the 1998 standard, which provides for the study of anatomical and physiological topics in the 9th grade, has not yet been fully completed.

The similarity of the two named standards is a list of the main proposed topics and issues under consideration: the body as a whole, the cells and tissues of the human body, the structure and functioning of organ systems, the main physiological processes of the body's vital activity, the principles of vital activity regulation, the relationship with the environment, the sense organs and the higher nervous activity, issues of hygiene and disease prevention. These topics are reflected in all textbooks approved and recommended by the Ministry of Education and Science of the Russian Federation, but their names may be different.

A feature of the 2004 educational standard is a clear separation of the levels of education (primary, basic 9-year, full 11-year) and levels of education for high school (basic and profile). The standard highlights the main learning objectives for the levels and levels, the mandatory minimum content of the main educational programs, requirements for the level of training of students.

The first block of requirements includes a list of topics, concepts and problems that schoolchildren should know (understand), they are grouped by headings: basic provisions, structure biological objects, the essence of processes and phenomena, modern biological terminology and symbolism. The second block includes the skills of schoolchildren: to explain, establish relationships, solve problems, draw up diagrams, describe objects, identify, research, compare, analyze and evaluate, and independently search for information. The third block provides requirements for the use of acquired knowledge and skills in practical activities and Everyday life: registration of results, first aid, observance of the rules of behavior in the environment, determination of one's own position and assessment of ethical aspects of biological problems.

Content educational standards implemented in educational literature... The textbook is one of the main sources of knowledge necessary for both getting students a new educational information, and to consolidate the material studied in the lesson. With the help of the textbook, the main goals and objectives of learning are solved: to ensure the mastery of students with various types of reproductive and creative learning activities on the basis of mastering the system of biological knowledge and skills of a theoretical and practical nature, to promote the development and education of schoolchildren.

Textbooks differ in content, as well as in structure, volume of educational information, methodological apparatus. However, a mandatory requirement for each textbook is the compliance of its content with the federal component state standard general secondary education in biology. The tutorial is currently a complex information system, around which other teaching aids are grouped (audio cassettes, computer support, Internet resources, notebooks on a printed basis, handouts, etc.), otherwise called an educational and methodological kit (TMC).

Let us give a brief description of the lines of textbooks recommended (admitted) for use in the educational process in educational institutions. Note that most textbooks are combined in lines, the content of which is reflected in the author's curricula, which have substantive and methodological differences in presentation. teaching material... A single line of textbooks ensures the continuity of biological education, a common approach to the selection of educational material, a developed methodological system for the formation and development of knowledge and skills.

Variable textbooks for the section "Man and his health" may differ in the sequence of topics, the depth of their coverage, the style of presentation, the volume of the laboratory practice, questions and tasks, methodological headings, etc.

Almost all of the offered curricula are concentric, i.e. basic 9-year education ends with the study of the section "General Biology". In each program, a leading idea is highlighted, which is consistently implemented in educational books for different sections of the biology course.

For textbooks developed by edited by N.I. Sonina, this is a functional approach, i.e. the priority of knowledge about the vital processes of organisms, which form the basis of the practical orientation of the content, as well as the reflection modern achievements biological science (Sonin N.I., Sapin M.R."Biology. Human").

The main ideas textbook lines developed by a team of authors edited by V.V. PaSechnik, we can consider biocentrism, strengthening of the practical orientation and the priority of the developmental function of learning ( Kolesov D.V., Mash R.D.,Belyaev I.N."Biology. Human").

In line established edited by I.N. Ponomareva, while maintaining the traditional structure of sections, the main conceptual ideas of the teaching materials are a multi-level and ecological-evolutionary approach to determining the content, and the educational material is presented according to the principle from general to specific ( Dragomilov A.G., Mash R.D."Biology. Human").

A distinctive feature of all textbooks line established under the leadership of D.I. Traitaka, Is a practice-oriented focus, implemented through textbook texts, a variety of practical workshops and illustrative material ( Rokhlov V.S., Trofimov S.B.

Selection of the content of educational material in line developed under the leadership of A.I. Nikishova, aimed at developing the cognitive abilities of schoolchildren. When selecting and structuring the content, a modern methodological apparatus was applied, providing for a two-level organization of the text, which makes it possible to differentiate learning ( Lyubimova Z.V., Marinova K.V."Biology. Man and His Health ").

In addition to the completed lines of textbooks, there are new, not yet completed lines. Educational books included in the recommended federal list meet modern educational standards.

Questions and tasks

1. Give a definition to the concepts: adaptation, hypothalamic-pituitary system, homeostasis.

2. Compare the regulatory processes that control the functions of the body (see table).

3. Write a short message