. The subject of age physiology and psychophysiology. General patterns of growth and development of children and adolescents.

Plan.

• 1. Introduction to the subject.
• 2. The organism as a whole.
• 3. The concept of growth and development.
• 4. Patterns of growth and development.
• 5. Age periodization. Periods of development of the body.

• Physiology is the science of functions, i.e. activity of organs, their systems and the organism as a whole. It studies the laws underlying the life processes of the body (the word "physiology" from the Greek nature and teachings, science).
• Age physiology is an independent branch of physiology.
It studies the characteristics of the body’s vital functions at different periods of ontogenesis (Greek creature, individual; development, origin; individual development of an individual from its inception in the form of egg fertilization to death), the function of organs, organ systems and the body as a whole as it grows and develops, its distinctiveness these functions at every age stage.
Psychophysiology (psychological physiology) is a scientific discipline that emerged at the junction of psychology and physiology, the subject of its study are the physiological bases of mental activity and human behavior.
• The task of the combined course “Age physiology and psychophysiology” is to equip students, future teacher-educators with up-to-date information on the age characteristics of the developing organism, knowledge of the laws underlying the preservation and strengthening of schoolchildren’s health, maintaining their high performance in various types learning activities.
Organism as a whole
The human body is a complex system hierarchically (co-ordinated) organized subsystems and systemically united by a common structure and function.
The element is a cell. In humans, more than 100 trillion cells. Cells are a microsystem characterized by a complex structural and functional organization and multilateral interaction with other cells.
A set of cells of similar origin, structure, and function forms a tissue.
• Tissues form organs. Organs occupy a permanent position in the body, have a special structure and perform a specific function. Thus, the heart plays the role of a pump and provides blood to all organs and tissues; the kidneys excrete end products of metabolism; the lungs carry out the gas exchange of the body with the external environment, providing the body with oxygen, etc. The body consists of several types of tissues, but one of them always prevails and determines its main leading function.
• Organs that jointly perform a specific function form a system of organs. For example, the salivary gland, the stomach, the liver, the pancreas, the intestines are integrated into the digestive system, the heart and blood vessels are integrated into the circulatory system.
• The activity of all structures of the body, starting with the cell and ending with the organ system, is consistent and subordinated to a single whole. Each structural unit contributes to the functioning of the organism, but the organism is not the sum of separate structures, but a whole and as a whole acquires its own special properties. Carries out its livelihoods and interacts with the environment.
• The functions of the whole organism are carried out only with close interaction with the environment. The body reacts to the environment and uses its factors for its existence and development.
• The ability to maintain the constancy of the chemical composition and physicochemical properties of the internal environment is called homeostasis. This constancy is maintained by the continuous work of the systems of the circulatory organs, respiration, digestion, excretion, etc., the release into the blood of biologically active chemical substances that ensure the interaction of cells and organs.
• In the body, the processes of self-regulation of physiological functions continuously occur, creating the conditions necessary for the organism to exist.
• Humoral regulation is one of the mechanisms of coordination of life processes in the body through the body fluids / blood, lymph, tissue fluid / with the help of biologically active substances secreted by cells, tissues and organs.
• The primary role played by the nervous regulation, which is carried out by the nervous system. The nervous system unites and connects all cells and organs into a single whole, changes and regulates their activity, provides communication of the organism with the environment. The central nervous system and its leading section, the cortex of the cerebral hemispheres, very subtly and accurately perceiving changes in the environment, as well as the internal state of the organism, by its activity ensures the development and adaptation of the organism to the constantly changing conditions of existence.

The concept of growth and development
The processes of growth and development are the general biological properties of living matter. The growth and development of a person, starting from the moment of fertilization of an egg, provide a continuous progressive process that takes place throughout his life. The development process proceeds abruptly. The difference - between individual stages, or periods of life, is reduced not only to quantitative, but also qualitative changes.
Under the development in the broad sense of the word should understand the process of quantitative and qualitative changes occurring in the human body, leading to increased levels of complexity of the organization and interaction of all its systems,
Development includes three main factors:
• growth,
• differentiation of organs and tissues,
• formation (acquisition by the body of characteristic, inherent forms.)
The main patterns of growth and development:
• continuity
• -uniformity (variability)
• -heterochronicity
• -individual development rate / consideration of individual and age-related developmental features.
On the basis of the richest factual material of age-related morphology and physiology, which is the natural science base of the physiology and hygiene of children and adolescents, the laws of growth and development of the child's body are established. These patterns apply both to the organism as a whole and to the development of its individual organs and tissues.
The younger the child's body, the more intense the processes of growth and development take place in it.
• A feature of the current generation is heterochronic development.
• Heterochronicity - the uneven development of mental functions of a person throughout life. For example, in the period of early adulthood (18-21 years), the level of some functions increases (volume of the field of view, eye, constancy of identification, differentiated recognition, spatial representation, attention), others decrease (visual acuity, short-term memory), the third remains stable (observation). After 30-35 years, there is a gradual decline in non-verbal functions, as far as verbal functions are concerned, they have been progressing most intensively from this period, reaching a high level after 40-45 years.
Heterochronicity is manifested in three forms:
• a) Retardation - the process of slow development or lagging behind in the pace of development, compared with their peers.
• b) Average rate of development.
• c) Acceleration - the process of advancing or accelerated development in comparison with their peers.
• Acceleration (from Lat. Acseleratio - acceleration) is accelerated physical and partly mental development in childhood and adolescence. Biologists associate acceleration with the physiological maturation of the organism, psychologists with the development of mental functions, and teachers with intellectual development and socialization of the individual.
Age periodization. Periods of development of the body.
• In the process of ontogenesis, separate organs and systems mature gradually and complete their development at different periods of life. This maturation heterochronia determines the functioning of the body of children of different ages. There is a need to highlight certain stages or periods of development. The main stages of development are prenatal and postnatal, starting from the moment of birth. During the prenatal period, tissues and organs are laid down, their differentiation occurs. The postnatal stage covers all childhood, it is characterized by the continuing maturation of organs and systems, changes in physical development, significant qualitative changes and restructuring of the functioning of the body.
• The heterochrony of the maturation of organs and systems in postnatal ontogenesis determines the specificity of the functional capabilities of the organism of children of different ages, the characteristics of its interaction with the external environment. Periodization of the development of the child's body is important for teaching practice and child health.
• Periodization includes a complex of signs, regarded as indicators of biological age: body and organ size, mass, skeletal ossification, teething, development of endocrine glands, degree of puberty, muscle strength. Each age period is characterized by its specific features. The transition from one age period to the next is designated as a crucial stage of individual development, or a critical period.
• The length of individual age periods is highly susceptible to change. Both the chronological framework of age and its characteristics are determined primarily by social factors.
• The chronological (“passport”) age characterizes the time period from the moment of birth of the organism to the present or any other moment and has clear gradations in time - day, month, year.
• Age as a biological concept (“biological age”) is a characteristic of an organism’s life, reflecting its growth, development, maturation and aging, i.e. its biological evolution. It is determined by a set of exchange, structural, functional, regulatory features and adaptive capabilities of the organism, that is, a set of morpho-functional indicators of the organism, peculiar to a certain stage of its ontogenetic development. Biological age may or may not correspond to the passport age, lagging behind or ahead of it.