The levels of organization of the human body. Levels of life organization of living systems 8 what levels of organization of the organism do you know

In this lesson, we will become familiar with the levels of organization of our body and its organ systems.

Topic: General overview of the human body

Lesson: Organ systems in the body. Organization levels

Our body. This definition seems so familiar and understandable that we rarely think about its essence. And to the question: "What is it all the same?" many may find it difficult to answer.

Organism is a certain complex or system that reacts as a whole to various changes in the external environment. This system is relatively stable, despite the fact that it consists of many organs. Organs, in turn, are made up of tissues, tissues - of cells, cells - of molecules.

Molecules, cells, tissues, organs, organ systems - all these floors, or different levels living, united in the human body into a single and indivisible whole.

Living organisms are built from special chemical compounds - organic matter(proteins, fats, carbohydrates, nucleic acids). They are part of any living cell. These large molecules act as building blocks that create complex complexes. Cell substances are located not chaotically, but form ordered structures - organelles, which provide the vital processes of the cell. The human body is a multicellular state. The cells of the human body are not the same, differ in their specialization. Cells of the same specialty are combined into groups. Together with the intercellular substance, they form tissues. Organs are composed of several tissues. Organs performing a single function and having a general plan of structure and development will unite into organ systems. All organ systems are interconnected and constitute a single organism.

There are 10 main organ systems in the human body.

Integumentary system- consists of the skin and mucous membranes lining the cavities of the internal organs, respiratory tract, and digestive tract. The function of this system is to protect the body from mechanical damage, drying out, temperature fluctuations, and the penetration of pathogenic bacteria.

1. Kolesov D.V., Mash R.D., Belyaev I.N. Biology 8 M.: Bustard - p. 49, tasks and question 1.

2. What is included in the urinary system?

3. What is included in the digestive system?

4. Prepare an abstract about one of the organ systems.

An organism is a historically formed integral, constantly changing system, which has its own special structure and difference, capable of metabolism with the environment, for growth and reproduction. The organism lives only under certain conditions. the environment to which he is adapted.

The body is built of separate private structures - organs, tissues and tissue elements, combined into a single whole.

In the process of evolution of living beings, first non-cellular life forms (protein "moneras", viruses, etc.), then cellular forms (unicellular and simplest multicellular organisms) arose. With the further complication of the organization, individual parts of organisms began to specialize in performing individual functions, thanks to which the organism adapted to the conditions of its existence. In this regard, specialized complexes of these structures - tissues, organs and, finally, complexes of organs - systems began to arise from non-cellular and cellular structures.

Reflecting this process of differentiation, the human body contains all these structures in its body. Cells in the human body, like all multicellular animals, exist only in tissues.

INTEGRITY OF THE ORGANISM

An organism is a living biological holistic system with the ability to reproduce itself, self-develop and self-rule. The organism is a single whole, moreover, the "highest form of integrity" (K. Marx). The body manifests itself as a whole in various aspects.

The integrity of the organism, that is, its unification (integration), is ensured, firstly: 1) the structural connection of all parts of the organism of cells, tissues, organs, fluids, etc.); 2) the connection of all parts of the body with the help of: a) fluids circulating in its vessels, cavities and spaces (humoral connection, humor - fluid), b) the nervous system, which regulates all processes of the body (nervous regulation).

In the simplest unicellular organisms that do not yet have a nervous system (for example, amoeba), there is only one type of connection - humoral. With the emergence of the nervous system, two types of communication arise - humoral and nervous, and as the organization of animals becomes more complex and the development of the nervous system, the latter more and more "takes possession of the body" and subordinates all processes of the body, including humoral, as a result of which a single neurohumoral regulation is created. with the leading role of the nervous system.

Thus, the integrity of the organism is achieved due to the activity of the nervous system, which permeates all organs and tissues of the body with its ramifications and which is the material anatomical substrate for the unification (integration) of the organism into a single whole, along with the humoral connection.

The integrity of the organism consists, secondly, in the unity of the vegetative (plant) and animal (animal) processes of the organism.

The integrity of the organism consists, thirdly, in the unity of spirit and body, the unity of the mental and somatic, bodily. Idealism separates the soul from the body, considering it independent and unknowable. Dialectical materialism believes that there is no psyche separated from the body. It is a function of the bodily organ - the brain, representing the most highly developed and specially organized matter, capable of thinking. Therefore, "it is impossible to separate thinking from the matter that thinks."

This is the modern understanding of the integrity of the organism, based on the principles of dialectical materialism and its natural scientific basis - the physiological doctrine of I.P. Pavlov.

The relationship of the organism as a whole and its constituent elements. The whole is a complex system the relationship of elements and processes, which has a special quality that distinguishes it from other systems, a part is a subordinate element of the system to the whole.

An organism as a whole is something more than the sum of its parts (cells, tissues, organs). This "more" is a new quality that has arisen due to the interaction of parts in the process of phylo - and ontogenesis. A special quality of an organism is its ability to exist independently in a given environment. So, a unicellular organism; e.g. amoeba) has the ability to independent life, and a cell that is part of the body (for example, a leukocyte) cannot exist outside the body and dies from the blood. Only with artificial

maintaining certain conditions can exist isolated organs and cells (tissue culture). But the functions of such isolated cells are not identical to the functions of cells of the whole organism, since they are excluded from the general exchange with other tissues.

The organism as a whole plays a leading role in relation to its parts, the expression of which is the subordination of the activity of all organs of neurohumoral regulation. Therefore, organs isolated from the body cannot perform those functions that are inherent in them within the framework of the whole organism. This explains the difficulty of organ transplantation. The organism as a whole can exist even after the loss of some parts, as evidenced by the surgical practice of operative removal of individual organs and parts of the body (removal of one kidney or one lung, amputation of limbs, etc.).

The subordination of the part to the whole is not absolute, since the part has relative independence.

Possessing relative independence, a part can affect the whole, as evidenced by changes in the whole organism in case of diseases of individual organs.

An organ (organon - tool) is a historically developed system of various tissues (often all four main groups), of which one or more predominate and determine its specific structure and function.

For example, in the heart there is not only striated muscle tissue, but also different kinds connective tissue (fibrous, elastic),

elements of the nervous (nerves of the heart), endothelium and smooth muscle fibers (vessels). However, the predominant is the cardiac muscle tissue, the property of which (contractility) determines the structure and function of the heart as an organ of contraction.

An organ is a holistic formation that has a certain form, structure, function, development and position in the body inherent only to it.

Some organs are built from many structures similar in structure, consisting in turn of various tissues. Each such part of the organ has everything necessary to carry out a function characteristic of the organ. For example, the acinus of the lung is a small part of an organ, but it contains epithelium, connective tissue, smooth muscle tissue in the walls of blood vessels, and nervous tissue ( nerve fibers). In the acinus, the main function of the lung is carried out - gas exchange. Such formations are called the structural and functional unit of the organ.

Each organism is characterized by a certain organization of its structures. There are six levels of organization human body:
1) molecular;
2) cellular:
3) tissue;
4) organ;
5) systemic.
6) organismic.

Molecular level of organization. Any living system no matter how complex it is organized, it manifests itself at the level of functioning of biological macromolecules (biopolymers): nucleic acids, proteins, fats (lipids), polysaccharides, vitamins, enzymes and other organic substances. Protein molecules, in turn, are broken down in the body into monomer molecules - amino acids, fats - into glycerol and fatty acid molecules, carbohydrates - into glucose molecules, etc. The most important life processes of the organism begin from the molecular level.

The cellular level of organization. A cell is an elementary structural, functional and genetic unit of a multicellular organism. There are approximately K) "4 cells in the human body. The cells of a complex organism are specialized

Each cell has a cell membrane, cytoplasm and nucleus. The membrane limits the internal environment of the cell, protects it from damage. regulates the metabolism between the cell and the environment, provides interconnection with other cells. Cytoplasm is the internal semi-liquid medium of the cell, to which the organelles of the cell are located, including the nucleus, which performs the functions of storing and transmitting hereditary information, regulating protein synthesis; nuclear division underlies cell multiplication

Tissue, organization level. Tissues are groups of cells and intercellular substance, united general structure, function and origin. There are four main groups of tissues: epithelial, connective, muscular and nervous.

Epithelial (borderline) tissue is located on surfaces bordering with the external environment, and lines the walls of hollow organs, blood vessels from the inside, is "part of the glands of the body. The epithelium has a" high ability to restore (regeneration), serves as a material for hair, nails, enamel tooth.

Connective tissues (tissues of the internal environment) perform nutritional, transport and protective (blood, lymph), as well as supporting (tendons, cartilage, bone tissue) functions. A type of connective tissue is adipose tissue.

Muscle tissue is divided into three types:

Striated (skeletal muscles, muscles of the tongue, pharynx, larynx);
- smooth (forms the walls of internal organs);
- cardiac (like skeletal, it has a striated structure, but like smooth muscles it contracts involuntarily).

Nerve tissue, consisting of nerve cells (neurons), is involved in conducting nerve impulses from various organs and tissues to the central nervous system and vice versa.

Organ level of organization. Various tissues, connecting with each other, form organs: heart, kidneys, lungs, brain, spinal cord, muscle, bladder, uterus, mammary gland, stomach, eye, ear, etc. The organ occupies a permanent position, has a definite structure, form and function. Organs, which are similar in structure, function and development, are combined into organ systems

The systemic level of the organization. A set of organs participating in the performance of any complex act of activity, forming anatomical and functional associations - organ systems. There are nine main body systems.

1. The system of organs of movement or the musculoskeletal system unites all bones (skeleton), their joints (joints, ligaments) and skeletal
muscles. Thanks to this system, the body moves in the external environment; bones of the skeleton protect internal organs from mechanical damage
(black - protects the brain, chest - the heart and lungs).
2. The digestive system unites organs that perform the functions of food intake, its mechanical and chemical processing, absorption
nutrients into the blood and lymph; and the removal of undigested parts of food. The digestive system consists of the mouth, pharynx, esophagus,
stomach, small and large intestines. The digestive system includes the salivary glands, liver, and pancreas.
3. The respiratory system carries out the consumption of oxygen by the body and the release of carbon dioxide... those. gas exchange function between
the body and the environment. The respiratory system includes the nasal cavity, larynx, trachea, bronchi and lungs.
4. The urinary system performs the function of excretion of the final metabolic products from the body and the function of maintaining constancy
the internal environment of the body (homeostasis). in particular, the water-salt balance. The urinary system includes the kidneys, bladder,
ureters and urethra.
5. The reproductive system unites the reproductive organs and performs the function of prolonging the human race. Distinguish between male and female reproductive systems., Which include the external and internal genital organs (gonads).
The "male genital organs include external (penis, scrotum) and internal (testes with appendages, vas deferens and ejaculatory ducts, seminal vesicles, prostate and Cooper glands). Testicles are paired male sex glands that produce male reproductive cells (sperm) and secrete in the blood male sex hormones - androgens.The process of growth and development of male germ cells is called spermatogenesis.
The female genital organs include external (large and small labia, clitoris) and internal (ovaries, uterine coarse, uterus, vagina). The uterus is a hollow muscular organ intended for carrying a fetus. Its inner layer (endometrium) is lined with mucous epithelium, which is renewed every menstrual cycle. The ovary is a paired female reproductive gland, in which the development and maturation of female reproductive cells (eggs) takes place, as well as the formation of female sex hormones - estrogens and progesterone. The process of release of a mature egg from the ovary is called ovulation.
6. The endocrine system consists of endocrine glands, which include the pituitary gland, pineal gland, thymus gland, thyroid,
pancreas, parathyroid. sex glands, adrenal glands. They produce special active substances (hormones) that directly
absorbed into the blood. Hormones are carried by the blood throughout the body and have a regulatory effect on various functions, primarily on metabolism.
substances, gene activity, processes of ontogenetic development, tissue differentiation, sex formation, reproduction, tone of the cerebral cortex
brain, etc.
7. The cardiovascular system (CVS) ensures the continuous movement of blood in the body (circulation), due to which
transport functions of blood are carried out: delivery of oxygen, nutrients and hormones to tissues and removal from tissues of substances formed as a result of metabolic processes. CVS includes the heart, blood vessels (arteries, veins, and capillaries), and lymphatic vessels. CCC plays an important role in the integration of the organism into a whole. Communication between organs is carried out through the blood and lymph.
8. The system of the senses combines the organs of sight, hearing, smell, bite and touch. They perceive] information from the external environment, play an important role in the exchange of information between the body and the environment.
9. The nervous system plays a leading role in uniting the organism into a single whole, regulates the activity of all internal organs and systems of the orcs. It carries out the connection of the body with the surrounding environment on the basis of conditioned and unconditioned reflexes, providing adaptation to changing living conditions, and also carries out human mental activity, arising on the basis of physiological processes of sensation, perception and thinking.

The nervous system includes the brain and spinal cord, nerves extending from them and all their ramifications. The brain and spinal cord form the central nervous system (CNS). The highest part of the central nervous system is the cerebral cortex. All the nerves extending from the brain and spinal cord are "!" peripheral nervous system. The activity of the spinal cord and peripheral nervous system is regulated by the overlying parts of the central nervous system. those. the brain.

The brain is located in the skull. It contains nerve centers that provide the most important functions of the body and human mental activity. The average brain mass of men is 1400 g, and that of women - 1300 g. These differences do not reflect mental ability, but the ratio of brain mass to body mass.

In the brain, the cerebral hemispheres and the brain stem are distinguished. The brain stem contains the centers of respiration, cardiac activity, digestion, coordination of movements and regulation of muscle tone, regulation of sensations by the senses, etc. These are the centers of unconditioned reflexes - innate responses of the body that provide important vital functions of the body: breathing, heartbeat, digestion, thermoregulation, maintaining muscle tone.

The large hemispheres (left and right) are composed of gray and white matter. Gray matter, consisting of the bodies of nerve cells, forms the cerebral cortex with a thickness of about 3-4 mm. The white matter, formed by the processes of nerve cells, is located under the cortex. There is an interhemispheric asymmetry between the right and left hemispheres of the brain. This means that the functions of both hemispheres are not exactly the same. For example, in right-handers (people whose main active hand is the right), the center of speech is in the left hemisphere. The left hemisphere in right-handers is the main nervous substrate of human consciousness and is called dominant

Frontal lobes large hemispheres in humans - the largest areas of the cortex (they are absent in animals, except for chimpanzees). One of the functions of the frontal lobe is to control innate behavioral responses using accumulated experience. For patients with affected frontal lobes of the cortex, impulsivity, incontinence, irritability and other manifestations of mental instability are characteristic. Such patients often become rude, tactless, although they retain intelligence, they often come into conflict with other people.

The cerebral cortex affects all functions of the body and provides a connection between the body and the external environment, causing the higher nervous activity of the body (mental activity, thinking, memory, speech, etc.). The centers of conditioned reflexes are located in the cerebral cortex. Conditioned reflexes- this is the knowledge acquired in the learning process, during life - skills and abilities. If, under damaging influences, cells of the cerebral cortex die, then the person is completely or partially deprived of the knowledge, skills and abilities he received earlier. Such an effect is possible with clinical death when cells of the cerebral cortex die from lack of oxygen. Memory is of great importance in a person's life. The information capacity of the human brain can only be roughly estimated. Inhabited information capacity of the brain! and a person is approximately equal to 3x10xbit (a bit is a unit of information). From all the information, surrounding man, only 1% goes to long-term memory.

The level of the whole organism. The human body functions as a whole and is a self-regulating system. The interconnected, coordinated work of all organs and physiological systems is provided by humoral and nervous regulation.

The human body is in constant interaction with abiotic and biotic factors of the environment, which affects and changes it. The origin of man has been of interest to science for a long time, and theories of his origin are different. This is the fact that man originated from a small cell, which gradually, forming colonies of cells of its own kind, became multicellular and in the process of a long course of evolution turned into a humanoid ape, and which, thanks to labor, became a man.

The concept of levels of organization of the human body

In the process of studying in general education high school in biology lessons, the study of a living organism begins with the study of the plant cell and its components. Already in high school, in the classroom, schoolchildren are asked the question: "Name the levels of organization of the human body." What it is?

Under the concept of "levels of organization of the human body" it is customary to understand its hierarchical structure from a small cell to organismic level... But this level is not the limit, and it is already completed by the supraorganism order, which includes the population-species and biosphere levels.

Highlighting the levels of organization of the human body, their hierarchy should be emphasized:

1. Molecular genetic level.
2. Cellular level.
3. Tissue level.
4. Organ level
5. Organizational level.

Molecular genetic level

The study of molecular mechanisms makes it possible to characterize it with such components as:

• carriers of genetic information - DNA, RNA.
• biopolymers are proteins, fats and carbohydrates.

At this level, genes and their mutations are distinguished as a structural element, which determine variability at the organismal and cellular level.

The molecular genetic level of organization of the human body is represented by genetic material, which is encoded in the DNA and RNA chain. Genetic information reflects such important components of the organization of human life as morbidity, metabolic processes, type of constitution, gender component and individual characteristics of a person.

The molecular level of organization of the human body is represented by metabolic processes, which consist of assimilation and dissimilation, regulation of metabolism, glycolysis, crossing over and mitosis, meiosis.

Property and structure of the DNA molecule

The main properties of genes are:

• convariant reduplication;
• the ability to local structural changes;
• transmission of hereditary information at the intracellular level.

The DNA molecule consists of purine and pyrimidine bases, which are connected according to the principle of hydrogen bonds with each other and an enzymatic DNA polymerase is required to connect and break them. Convariant reduplication occurs according to the matrix principle, which ensures their connection at the remainder of the nitrogenous bases of guanine, adenine, cytosine, and thymine. This process takes 100 seconds, and during this time 40 thousand base pairs are collected.

Cellular level of organization

The study of the cellular structure of the human body will help to understand and characterize cellular level organization of the human body. The cell is a structural component and consists of elements periodic system DI Mendeleev, of which the most predominant are hydrogen, oxygen, nitrogen and carbon. The rest of the elements are represented by a group of macronutrients and micronutrients.

Cell structure

The cage was discovered by R. Hooke in the 17th century. The main structural elements cells are the cytoplasmic membrane, cytoplasm, cell organelles and nucleus. The cytoplasmic membrane consists of phospholipids and proteins like structural components to provide the cell with pores and channels for the exchange of substances between cells and the receipt, removal of substances from them.

Cell nucleus

The cell nucleus consists of the nuclear envelope, nuclear juice, chromatin and nucleoli. The nuclear envelope performs a form-building and transport function. Nuclear juice contains proteins that are involved in the synthesis of nucleic acids.

• storage of genetic information;
• reproduction and transmission;
• regulation of cell activity in its life-supporting processes.

Cell cytoplasm

The cytoplasm consists of general purpose and specialized organelles. General purpose organelles are divided into membrane and non-membrane.

The main function of the cytoplasm is the constancy of the internal environment.

Membrane organelles:

• Endoplasmic reticulum. Its main tasks are the synthesis of biopolymers, intracellular transport of substances, and is a depot of Ca + ions.
• Golgi apparatus. It synthesizes polysaccharides, glycoproteins, participates in protein synthesis after it leaves the endoplasmic reticulum, transports and ferments secretions in the cell.
• Peroxisomes and lysosomes. They digest absorbed substances and break down macromolecules, neutralize toxic substances.
• Vacuoles. Storage of substances, metabolic products.
• Mitochondria. Energy and respiratory processes inside the cell.

Non-membrane organelles:

• Ribosomes. Proteins are synthesized with the participation of RNA, which transfers from the nucleus genetic information about the structure and synthesis of protein.
• Cell center. Participates in cell division.
• Microtubules and microfilaments. They carry out a supportive and contractile function.
• Cilia.

Specialized organelles are the sperm acrosome, microvilli of the small intestine, microtubules and microcilia.

Now, to the question: "Characterize the cellular level of organization of the human body", we can safely list the components and their role in the organization of the structure of the cell.

Tissue level

In the human body, it is impossible to distinguish a level of organization in which some tissue, consisting of specialized cells, would not be present. Tissues are composed of cells and intercellular substance and, according to their specialization, are subdivided into:

• Nervous. It integrates the external and internal environment, regulates metabolic processes and higher nervous activity.

The levels of organization of the human body smoothly pass into each other and form an integral organ or a system of organs that line many tissues. For example, the gastrointestinal tract, which has a tubular structure and consists of a serous, muscular and mucous layer. In addition, it has blood vessels feeding it and a neuromuscular apparatus, which is controlled nervous system, also a variety of enzymatic and humoral control systems.

Organ level

All levels of organization of the human body, listed earlier, are components of organs. Organs perform specific functions to ensure the constancy of the internal environment, metabolism in the body and form systems of subordinate subsystems that perform specific function the body. For example, the respiratory system consists of the lungs, airways, and respiratory center.

The levels of organization of the human body as a whole represent an integrated and fully self-sustaining organ system that forms the body.

The body as a whole

The union of systems and organs forms an organism in which the integration of the work of systems, metabolism, growth and reproduction, plasticity, irritability is carried out.

There are four types of integration: mechanical, humoral, nervous and chemical.

Mechanical integration is carried out by the intercellular substance, connective tissue, and auxiliary organs. Humoral - blood and lymph. Nervous is the highest level of integration. Chemical - hormones of the endocrine glands.

The levels of organization of the human body are a hierarchical complication in the structure of his body. The body as a whole has a physique - an external integrated form. Physique is an external person, which has different sex and age characteristics, structure and position of internal organs.

Distinguish between asthenic, normosthenic and hypersthenic body types, which are differentiated by growth, skeleton, musculature, presence or absence of subcutaneous fat. Also, in accordance with the type of physique, organ systems have a different structure and position, size and shape.

The concept of ontogeny

The individual development of an organism is determined not only by genetic material, but also by external environmental factors. The levels of organization of the human body, the concept of ontogeny, or individual development organism in the process of its development, uses different genetic materials involved in the functioning of the cell in the process of its development. The work of genes is influenced by the external environment: through environmental factors, renewal occurs, the emergence of new genetic programs, mutations.

For example, hemoglobin changes three times over the entire development of the human body. The proteins that synthesize hemoglobin go through several stages from embryonic hemoglobin, which passes into fetal hemoglobin. In the process of maturation of the body, hemoglobin passes into the form of an adult. These ontogenetic characteristics of the level of development of the human body briefly and clearly emphasize that the genetic regulation of the organism plays an important role in the development of the organism from the cell to the systems and the organism as a whole.

The study of the organization allows you to answer the question: "What are the levels of organization of the human body?" The human body is regulated not only by neuro-humoral mechanisms, but also by genetic ones, which are located in every cell of the human body.

The levels of organization of the human body can be briefly described as a complex subordinate system, which has the same structure and complexity as the entire system of living organisms. This pattern is an evolutionarily fixed feature of living organisms.