The body is the basic unit of life, the real carrier of its properties, since life processes occur only in the cells of the body. As a separate individual, the organism is part of the species and population, being a structural unit of the population-species standard of living.
Biosystems at the organismal level have the following properties: Metabolism Nutrition and digestion Respiration Excretion Irritability Reproduction Behavior Lifestyle Mechanisms of adaptation to the environment Neurohumoral regulation of vital processes
The structural elements of the body are cells, cell tissues, organs and organ systems with their unique vital functions. The interaction of these structural elements in their totality ensures the structural and functional integrity of the organism.
The main processes in the biosystem of the organism level: metabolism and energy, characterized by the coordinated activity of various organ systems of the body: maintaining the constancy of the internal environment, deploying and implementing hereditary information, as well as checking the viability of a given genotype, individual development (ontogenesis).
The organization of a biosystem at the organismal level is distinguished by a wide variety of organ and tissue systems that form an organism; the formation of control systems that ensure the coordinated operation of all components of the biosystem and the survival of the organism in difficult environmental conditions; the presence of various mechanisms of adaptation to the action of factors that maintain the relative constancy of the internal environment, i.e., homeostasis of the body.
The significance of the organismic level of life in nature is expressed primarily in the fact that at this level a primary discrete biosystem arose, characterized by self-maintenance of its structure, self-renewal, actively regulating the impact of the external environment and able to interact with other organisms.
The vital activity of the body is provided by the work and interaction of its various organs. An organ is a part of a multicellular organism that performs a specific function (or a group of interrelated functions), has a certain structure and consists of a naturally formed complex of tissues. An organ can perform its functions on its own or as part of an organ system (eg, respiratory, digestive, excretory, or nervous).
In unicellular organisms, the functional parts of individuals are organelles, that is, structures similar to organs. An organism is a collection of organ systems connected to each other and the external environment.
All organisms as separate individuals are representatives of various populations (and species) and carriers of their main hereditary properties and traits. Therefore, each organism is a unique example of a population (and species) in the manifestation of hereditary inclinations, traits and relationships with the environment.
Humoral regulation is carried out through the liquid media of the body (blood, lymph, tissue fluid) with the help of biologically active substances secreted by cells, tissues and organs during their functioning. In this case, an important role is played by hormones, which, being produced in special endocrine glands, enter directly into the blood. In plants, the processes of growth and morphophysiological development are controlled by biologically active chemical compounds - phytohormones produced by specialized tissues (meristem at growth points).
In unicellular organisms (protozoa, algae, fungi), many vital processes are also regulated by humoral-chemical means through the external and internal environment.
In the course of the evolution of living organisms, a new regulation, more efficient in terms of the speed of managing the processes of functioning, emerged - nervous regulation. Nervous regulation is a phylogenetically younger type of regulation compared to humoral regulation. It is based on reflex connections and is addressed to a strictly defined organ or group of cells. The speed of nervous regulation is hundreds of times higher than that of humoral regulation.
Homeostasis is the ability to resist changes and maintain dynamically the relative constancy of the composition and properties of the organism.
In vertebrates and humans, the impulses sent by the nervous system and the secreted hormones complement each other in the regulation of the vital processes of the organism. Humoral regulation is subordinated to nervous regulation, together they constitute a single neurohumoral regulation that ensures the normal functioning of the body in changing environmental conditions.
Nutrition of unicellular Pinocytosis is the absorption of fluid and ions. Phagocytosis is the capture of solid particles. The cell can digest with the help of lysosomes. Lysosomes digest almost everything, even the contents of their cells. The process of cell self-destruction is called autolysis. Autolych occurs when the contents of lysosomes are released directly into the cytoplasm.
The movement of unicellular organisms is carried out with the help of various organelles and outgrowths of the cytoplasm. In the cytoplasm there is a complex network of microtubules, microfilaments and other structures that have supporting and contractile functions that provide amoeboid movement of the cell. Some protozoa move by undulating contraction of the entire body. The cell performs active movement with the help of such special formations as flagella and cilia.
The behavior (irritability) of unicellular organisms manifests itself in the fact that they can perceive various stimuli from the external environment and respond to them. As a rule, the response to irritation consists in the spatial movement of individuals. This type of irritability in unicellular organisms is called taxis. Phototaxis is an active response to light. Thermotaxis is an active response to temperature. Geotaxis is an active reaction to the attraction of the earth.
Multicellular organisms, like unicellular organisms, are inherent in the basic processes of life: nutrition, respiration, excretion, movement, irritability, etc. However, unlike unicellular organisms, in which all processes are concentrated in one cell, multicellular organisms have a division of functions between cells, tissues, organs and organ systems.
The vascular systems transport substances within the body. The respiratory system supplies the body with the necessary amount of oxygen and simultaneously removes many metabolic products. The use of oxygen dissolved in water is the most ancient way of breathing. For this, gills are used. In terrestrial vertebrates, the respiratory system consists of the larynx, trachea, paired bronchi and lungs.
The processes of respiration and excretion of metabolic products in many highly organized animals, especially those with large sizes, are impossible without the participation of the circulatory system. CS first appeared in worms. Arthropods, mollusks and chordates have a special pulsating organ in the CS - the heart. In addition to the main role (providing metabolic processes and maintaining homeostasis), the CS of vertebrates also performs other functions: it maintains a constant body temperature, transfers hormones, participates in the fight against diseases, in wound healing, etc.
Blood is a liquid tissue that circulates in the circulatory system. All vertebrates have cellular or shaped elements in their blood. These are erythrocytes, leukocytes and platelets.
Tasks and questions 1. Describe the differences between the organismic standard of living and the population-species standard. 2. Using the example of any mammal, name the main structural elements of the "organism" biosystem. 3. Explain what signs make it possible to attribute to organisms the tuberculosis bacillus in a patient, a perch in a river, and a pine tree in a forest. 4. Describe the role of control mechanisms in the existence of a biosystem. 5. How is self-regulation of vital processes carried out in the body? 6. Explain how unicellular organisms absorb and digest food. Describe how unicellular organisms navigate in the environment.
All living organisms in nature consist of the same levels of organization; this is a characteristic biological pattern common to all living organisms.
The following levels of organization of living organisms are distinguished - molecular, cellular, tissue, organ, organism, population-species, biogeocenotic, biospheric.
Rice. 1. Molecular genetic level
1. Molecular genetic level. This is the most elementary level characteristic of life (Fig. 1). No matter how complex or simple the structure of any living organism, they all consist of the same molecular compounds. An example of this is nucleic acids, proteins, carbohydrates and other complex molecular complexes of organic and inorganic substances. They are sometimes called biological macromolecular substances. At the molecular level, various life processes of living organisms take place: metabolism, energy conversion. With the help of the molecular level, the transfer of hereditary information is carried out, individual organelles are formed and other processes occur.
Rice. 2. Cellular level
2. Cellular level. The cell is the structural and functional unit of all living organisms on Earth (Fig. 2). Individual organelles in the cell have a characteristic structure and perform a specific function. The functions of individual organelles in the cell are interconnected and perform common life processes. In unicellular organisms (unicellular algae and protozoa), all life processes take place in one cell, and one cell exists as a separate organism. Remember unicellular algae, chlamydomonas, chlorella and protozoa - amoeba, infusoria, etc. In multicellular organisms, one cell cannot exist as a separate organism, but it is an elementary structural unit of the organism.
Rice. 3. Tissue level
3. Tissue level. A set of cells and intercellular substances similar in origin, structure and functions forms a tissue. The tissue level is typical only for multicellular organisms. Also, individual tissues are not an independent integral organism (Fig. 3). For example, the bodies of animals and humans are made up of four different tissues (epithelial, connective, muscle, and nervous). Plant tissues are called: educational, integumentary, supporting, conductive and excretory. Recall the structure and functions of individual tissues.
Rice. 4. Organ level
4. Organ level. In multicellular organisms, the union of several identical tissues, similar in structure, origin, and functions, forms the organ level (Fig. 4). Each organ contains several tissues, but among them one is the most significant. A separate organ cannot exist as a whole organism. Several organs, similar in structure and function, unite to form an organ system, for example, digestion, respiration, blood circulation, etc.
Rice. 5. Organism level
5. Organism level. Plants (chlamydomonas, chlorella) and animals (amoeba, infusoria, etc.), whose bodies consist of one cell, are an independent organism (Fig. 5). A separate individual of multicellular organisms is considered as a separate organism. In each individual organism, all the vital processes characteristic of all living organisms take place - nutrition, respiration, metabolism, irritability, reproduction, etc. Each independent organism leaves behind offspring. In multicellular organisms, cells, tissues, organs and organ systems are not a separate organism. Only an integral system of organs specialized in performing various functions forms a separate independent organism. The development of an organism, from fertilization to the end of life, takes a certain period of time. This individual development of each organism is called ontogeny. An organism can exist in close relationship with the environment.
Rice. 6. Population-species level
6. Population-species level. A set of individuals of one species or group that exists for a long time in a certain part of the range relatively apart from other sets of the same species constitutes a population. At the population level, the simplest evolutionary transformations are carried out, which contributes to the gradual emergence of a new species (Fig. 6).
Rice. 7 Biogeocenotic level
7. Biogeocenotic level. The totality of organisms of different species and organization of varying complexity, adapted to the same environmental conditions, is called a biogeocenosis, or natural community. The composition of biogeocenosis includes numerous types of living organisms and environmental conditions. In natural biogeocenoses, energy is accumulated and transferred from one organism to another. Biogeocenosis includes inorganic, organic compounds and living organisms (Fig. 7).
Rice. 8. Biosphere level
8. Biosphere level. The totality of all living organisms on our planet and their common natural habitat constitutes the biospheric level (Fig. 8). At the biospheric level, modern biology solves global problems, such as determining the intensity of the formation of free oxygen by the Earth's vegetation cover or changes in the concentration of carbon dioxide in the atmosphere associated with human activities. The main role at the biospheric level is played by "living substances", that is, the totality of living organisms that inhabit the Earth. Also at the biospheric level, "bio-inert substances" are important, formed as a result of the vital activity of living organisms and "inert" substances (i.e., environmental conditions). At the biospheric level, the circulation of substances and energy on Earth takes place with the participation of all living organisms of the biosphere.
levels of organization of life. population. Biogeocenosis. Biosphere.
- Currently, there are several levels of organization of living organisms: molecular, cellular, tissue, organ, organism, population-species, biogeocenotic and biospheric.
- At the population-species level, elementary evolutionary transformations are carried out.
- The cell is the most elementary structural and functional unit of all living organisms.
- A set of cells and intercellular substances similar in origin, structure and functions forms a tissue.
- The totality of all living organisms on the planet and their common natural habitat constitutes the biospheric level.
- List the levels of organization in order.
- What is fabric?
- What are the main parts of a cell?
- What organisms are characterized by the tissue level?
- Describe the organ level.
- What is a population?
- Describe the organism level.
- Name the features of the biogeocenotic level.
- Give examples of the interconnectedness of the levels of organization of life.
Complete the table showing the structural features of each level of the organization:
| Serial number |
Organization levels |
Peculiarities |
Get students ready for work.
1. What does biology study?
2. Knowledge of what natural science laws is the basis of the scientific worldview and is necessary for solving practical problems?
3. By what principle is the division of biology into separate sciences?
4. Why optimal use of wildlife?
5. What is life?
6. What levels of life organization do you know?
7. What levels of life organization have you already studied?
8. What is the elementary unit and structural elements of the organismic level?
9. How are living organisms classified?
10. What are the main processes taking place at the organism level?
11. Name the meaning and role of the organismic level in nature.
A. The difference between living and non-living.
Work in groups on assignments:
(Students answer the question, justify their opinion).
Group #1:
Can the following organisms be called alive and why:
a) animals in a state of suspended animation;
b) a person under anesthesia;
c) bacteria in the dried state;
d) dry yeast
Group #2:
The constancy of the structural and functional organization of biological systems - homeostasis - as a prerequisite for the existence of biological systems.
Group #3:
What phenomenon, characteristic of all living systems, underlies the following facts:
1) a frog cannot live in salt water, but in fresh water it excretes a lot of urine;
2) live herring in sea water "unsalted";
3) in human blood containing water, it is necessary to inject saline.
Group #4:
1. Give examples of wildlife systems.
2. Name examples of systems of inanimate nature.
Conclusion: metabolic processes in living matter provide homeostasis - the constancy of the structural and functional organization of the system.
B). Properties of living organisms:
- The unity of the chemical composition.
- The exchange of matter and energy (metabolism).
- 3. Rhythm.
- 4.Self-regulation
- Self-reproduction.
- Heredity.
- Variability.
- A single level of organization of living organisms
- Growth and development.
2. Irritability.
3. Discreteness.
4. Adaptability
Choose those signs of living organisms that were not discussed in the text of the textbook.
(discreteness, self-regulation, rhythm).
Conclusion: living organisms differ sharply from non-living systems in their exceptional complexity and high structural and functional orderliness. These differences give life qualitatively new properties.
AT). The main levels of organization of living organisms Wildlife is a complexly organized hierarchical system. Scientists, based on the characteristics of the manifestation of the properties of living matter, distinguish several levels of organization of living matter.
Molecular cell tissue organ
(molecule) (cell) (tissue) (organ)
organismal population-species
(organism) (species, population)
Biogeocenotic (ecosystem) biospheric.
(BHC, ecosystem) (biosphere)
The diagram shows the individual levels of life organization, their connection with each other, the flow of one from the other and shows the integrity of living nature.
- Group:
- Molecular.
- Cellular.
2nd group:
1. Tissue
2. Organ.
- Group:
1. Organismic.
- Population-species.
In the course of explaining the levels of organization of living organisms in groups, students of the class fill out the proposed table:
Organization levels |
biological system |
Elements that form the system |
|
Molecular |
Organelles |
Atoms and molecules |
|
Cellular |
Cell (organism) |
Organelles |
|
Tissue |
|||
Organ |
|||
Organismic |
organism |
Organ systems |
|
population-species |
population |
||
Biogeocenotic (ecosystem) |
Biogeocenosis (ecosystem) |
Populations |
|
biospheric |
Biosphere |
Biogeocenoses (ecosystems) |
Conclusion: the structure of living systems is characterized by discreteness, i.e. divided into functional units. So, atoms consist of elementary particles, molecules consist of atoms, molecules (large and small) form organelles that form cells, tissues form from cells, and organs form from them, etc.
The allocation of individual levels of life organization is to some extent conditional, since they are closely interconnected and follow one from the other, which indicates the integrity of living nature.
What forms of organisms are found on Earth?
What is the importance of the organism in nature?
Answer the question using the textbook pages 5-6 and arrange in the form of a diagram
The meaning of the body
- Whiteboard work:
Match the pictures according to the levels of organization of living organisms
A) molecular
B) Cellular
B) tissue
D) Organ
D) Organismic
E) Population-species
G) Biogeocenotic (ecosystem)
H) Biospheric
Problem solving:
- "Ozone holes" and the impact of UV rays on the cellular and molecular levels of life.
- The impossibility of treating a person without knowing the features of the structure and functioning of cells.
- To solve what global problems of mankind, knowledge of biology is necessary?
- Give examples of the use of biological science methods from botany, zoology, human anatomy and physiology.
paragraph 1.2 fill in the table.
Creative task in groups: What is the importance of biology for understanding all living things. How did you feel while studying this topic?
The following levels of life organization are distinguished: molecular, cellular, organ-tissue (sometimes they are separated), organismic, population-species, biogeocenotic, biospheric. Living nature is a system, and the various levels of its organization form its complex hierarchical structure, when the underlying simpler levels determine the properties of the overlying ones.
So complex organic molecules are part of the cells and determine their structure and vital activity. In multicellular organisms, cells are organized into tissues, and several tissues form an organ. A multicellular organism consists of organ systems, on the other hand, the organism itself is an elementary unit of a population and biological species. The community is represented by interacting populations of different species. The community and the environment form a biogeocenosis (ecosystem). The totality of ecosystems of the planet Earth forms its biosphere.
At each level, new properties of living things arise, which are absent at the underlying level, their own elementary phenomena and elementary units are distinguished. At the same time, the levels largely reflect the course of the evolutionary process.
The allocation of levels is convenient for studying life as a complex natural phenomenon.
Let's take a closer look at each level of organization of life.
Molecular level
Although molecules are made up of atoms, the difference between living matter and non-living matter begins to manifest itself only at the level of molecules. Only the composition of living organisms includes a large number of complex organic substances - biopolymers (proteins, fats, carbohydrates, nucleic acids). However, the molecular level of organization of living things also includes inorganic molecules that enter cells and play an important role in their life.
The functioning of biological molecules underlies the living system. At the molecular level of life, metabolism and energy conversion are manifested as chemical reactions, the transfer and change of hereditary information (reduplication and mutations), as well as a number of other cellular processes. Sometimes the molecular level is called the molecular genetic level.
Cellular level of life
It is the cell that is the structural and functional unit of the living. There is no life outside the cell. Even viruses can exhibit the properties of a living being only once they are in the host cell. Biopolymers fully show their reactivity when organized in a cell, which can be considered as a complex system of molecules interconnected primarily by various chemical reactions.
At this cellular level, the phenomenon of life manifests itself, the mechanisms of transmission of genetic information and the transformation of substances and energy are conjugated.
Organ tissue
Only multicellular organisms have tissues. Tissue is a collection of cells similar in structure and function.
Tissues are formed in the process of ontogenesis by differentiation of cells that have the same genetic information. At this level, cell specialization occurs.
Plants and animals have different types of tissues. So in plants it is a meristem, a protective, basic and conductive tissue. In animals - epithelial, connective, muscular and nervous. The fabrics may include a list of subfabrics.
An organ usually consists of several tissues, united among themselves in a structural and functional unity.
Organs form organ systems, each of which is responsible for an important function for the body.
The organ level in unicellular organisms is represented by various cell organelles that perform the functions of digestion, excretion, respiration, etc.
Organismal level of organization of living
Along with the cellular at the organismal (or ontogenetic) level, separate structural units are distinguished. Tissues and organs cannot live independently, organisms and cells (if it is a unicellular organism) can.
Multicellular organisms are made up of organ systems.
At the organismic level, such phenomena of life as reproduction, ontogeny, metabolism, irritability, neuro-humoral regulation, homeostasis are manifested. In other words, its elementary phenomena constitute regular changes in the organism in individual development. The elementary unit is the individual.
population-species
Organisms of the same species, united by a common habitat, form a population. A species usually consists of many populations.
Populations share a common gene pool. Within a species, they can exchange genes, that is, they are genetically open systems.
In populations, elementary evolutionary phenomena occur, ultimately leading to speciation. Living nature can evolve only in supra-organismal levels.
At this level, the potential immortality of the living arises.
Biogeocenotic level
Biogeocenosis is an interacting set of organisms of different species with different environmental factors. Elementary phenomena are represented by matter-energy cycles, provided primarily by living organisms.
The role of the biogeocenotic level consists in the formation of stable communities of organisms of different species, adapted to living together in a certain habitat.
Biosphere
The biospheric level of life organization is a higher-order system of life on Earth. The biosphere encompasses all manifestations of life on the planet. At this level, the global circulation of substances and the flow of energy (covering all biogeocenoses) take place.
Updating knowledge What is life? What levels of organization of life do you know? What levels of organization of life have already been studied? What is the elementary unit and structural elements of the organismic level? How are living organisms classified? What are the main processes taking place at the organism level? Name the meaning and role of the organism level in nature.
Life is the highest in comparison with the physical and chemical form of the existence of matter, naturally arising under certain conditions in the process of its development. Living objects differ from non-living ones in metabolism by an indispensable condition of life, the ability to reproduce, grow, actively regulate their composition and functions, to various forms of movement, irritability, adaptability to the environment, etc.
1. Globe 2. Savannah bask.77a/0_60627_c2e1a16f_XLhttp://img-fotki.yandex.ru/get/5507/mr-serg-bask.77a/0_60627_c2e1a16f_XL 3. Boar family in the forest fotki.yandex.ru/get/ 6601/ f/0_76b3b_d7ea102e_XL http://img-fotki.yandex.ru/get/6601/ f/0_76b3b_d7ea102e_XL 8. Blood cells 9. Chlorella jpg 10.smear neurons.jpghttp://facstaff.bloomu.edu/jhranitz/Courses/APHNT/Lab_Pictures/nerve_smear.jpg 11.zwitterion-3D-balls-1 molecule.pnghttp://aminoacidsbcaa.com/wp-content /uploads/2012/10/L-Glutamine-zwitterion-3D-balls-1. png 12. DNA
