Purpose of the lecture: explain the levels of organization of living organisms, give the concept of living environments and habitats. Familiarize yourself with the various adaptive capabilities of organisms to their environment.
Lecture outline:
1. Levels of organization of living organisms
2. Potential reproduction capabilities of organisms
3. Basic living environments. The concept of habitat
4. Ways of adaptation of organisms to the environment
Basic concepts on the topic: levels of organization: tissue, molecular, cellular, organismal, population, biocenosis, biosphere, nekton, plankton, benthos, geofilter, geophiles, geoxenes, microbiota, mesobiota, macrobiota.
In ecology, an organism is considered as an integral system that interacts with the external environment, both abiotic and biotic.
The main levels of life organization are distinguished - gene, cell, organ, organism, population, biocenosis, ecosystem, biosphere.
Molecular-the lowest level in which the biological system manifests itself in the form of the functioning of biologically active large molecules - proteins, nucleic acids, carbohydrates; cellular– the level at which biologically active molecules are combined into a single system. With regard to cellular organization, all organizations are divided into unicellular and multicellular; fabric– the level at which a combination of homogeneous cells forms tissue; organ– the level at which several types of tissues functionally interact and form a specific organ; organismic– the level at which the interaction of a number of organs is reduced into a single system of the individual organism; population– species, where there is a set of certain homogeneous organisms connected by a common origin, way of life and habitat; biocenosis and ecosystem– a higher level of organization of living matter, uniting organisms of different species composition; biosphere- the level at which the highest natural system was formed, covering all manifestations of life within our planet. At this level, all cycles of matter occur on a global scale associated with the life of organisms (see Fig. 1).
Of all the above levels of life organization, the object of ecology research is only the supraorganismal components of this structure, starting with organisms including the biosphere.
The world around us consists of organisms. Any organism is mortal and sooner or later dies, but life on Earth has continued and flourished for about 4 billion years.
Fig. 1 Levels of organization of living organisms
Living organisms constantly reproduce themselves in a series of generations, which is not characteristic of inanimate bodies. It is the ability to reproduce that allows species to exist in nature for a very long time, despite the fact that each individual lives for a limited time. The ability to reproduce itself is the main property of life. Even the slowest breeding species can produce so many individuals in a short time that there is not enough room for them on the globe. For example, in just five generations, i.e. in one to one and a half summer months, one single aphid can leave more than 300 million descendants. If species were allowed to reproduce freely, without restrictions, the numbers of any of them would grow exponentially, despite the fact that some produce only a few eggs or young in a lifetime, while others produce thousands or even millions of embryos that can grow into adult organisms . In fact, all living organisms have the ability to reproduce indefinitely. However, not one species is able to fully realize the unlimited ability to reproduce that it possesses. The main limiter to the unlimited proliferation of organisms is the lack of resources, the most necessary: for plants - mineral salts, carbon dioxide, water, light; for animals - food, water; for microorganisms – the various compounds they consume. The supply of these resources is not endless, and this inhibits the reproduction of species. The second limiter is the influence of various unfavorable conditions that slow down the growth and reproduction of organisms. For example, the growth and ripening of plants are highly dependent on the weather, in particular on temperature changes, etc. In nature, there is also a huge elimination, the death of embryos that have already been born or growing young individuals. For example, the thousands of acorns that one large oak produces annually end up being eaten by squirrels, wild boars, etc., or are attacked by fungi and bacteria, or die at the seedling stage for various reasons. As a result, only a few acorns grow into mature trees. One important pattern has been noted: those species that have a very high mortality rate in nature are distinguished by high fertility. Thus, high fecundity does not always lead to high abundance of a species. Survival, growth and reproduction, the number of organisms is the result of their complex interactions with their environment.
The environment of each organism is composed of many elements of inorganic and organic nature and elements introduced by man as a result of his economic activities. The environment includes the entire natural environment (that arose on Earth regardless of man) and the technogenic environment (created by man). Concept environment was introduced by the biologist J. Uksküll, who believed that living beings and their habitats are interconnected and together form a single system - the reality around us. In the process of adaptation to the environment, the body, interacting with it, gives and receives various substances, energy, and information. The environment is everything that surrounds the body and directly or indirectly affects its condition and functioning. The environment that allows organisms to live on Earth is very diverse.
On our planet, four qualitatively different environments of life can be distinguished: aquatic, ground-air, soil and living organisms. The living environments themselves are also very diverse. For example, water as a living environment can be sea or fresh, flowing or standing. In this case we talk about habitat. For example, a lake is an aquatic habitat. Organisms living in the aquatic environment - aquatic organisms - are divided according to their habitat into nekton, plankton and benthos. Nekton is a collection of floating, freely moving organisms. They are able to overcome long distances and strong currents (whales, fish, etc.). Plankton is a collection of floating organisms that move mainly with the help of currents and are not capable of rapid movement (algae, protozoa, crustaceans). Benthos is a collection of organisms living at the bottom of water bodies, slowly moving or attached (algae, sea anemone, etc.) In turn, habitats are distinguished in habitats. So, in the aquatic environment of life, in the habitat of a lake, habitats can be distinguished: in the water column, at the bottom, near the surface, etc. About 150,000 species live in the aquatic environment. The main abiotic factors of the aquatic environment: water temperature, water density and viscosity, water transparency, water salinity, light conditions, oxygen, water acidity. Aquatic organisms have less ecological plasticity than terrestrial ones, since water is a more stable environment, and its factors undergo relatively minor fluctuations. One of the features of the aquatic environment is the presence in it of a large number of small particles of organic matter - detritus, formed by dying plants and animals. Detritus is a high-quality food for many aquatic organisms, so some of them, the so-called biofilters, are adapted to extract it using special microporous structures, filtering the water and retaining particles suspended in it. This method of feeding is called filtration: biofilters include bivalves, sessile echinoderms, ascidians, planktonic crustaceans and others. Animals - biofilters play an important role in the biological purification of water bodies.
Organisms living on the surface of the Earth are surrounded by a gaseous environment characterized by low humidity, density and pressure, as well as a high oxygen content. The environmental factors operating in the ground-air environment differ in a number of specific features: compared to other environments, light here is more intense, temperature undergoes stronger fluctuations, humidity varies significantly depending on the geographical location, season and time of day. The impact of almost all of these factors is closely related to the movement of air masses - winds. In the process of evolution, organisms that inhabit the ground-air environment have developed specific anatomy - morphological, physiological, behavioral and other adaptations. They acquired organs that ensure direct assimilation of atmospheric air; skeletal formations that support the body in conditions of low environmental density have become strongly developed; complex devices were developed to protect against adverse factors; a closer connection with the soil was established; greater mobility of animals in search of food has developed; flying animals and fruits, seeds, and pollen carried by air currents appeared. The ground-air environment is characterized by clearly defined zonality; distinguish between latitudinal and meridional or longitudinal natural zones. The former stretch from west to east, the latter from north to south.
Soil as a living environment has unique biological characteristics, since it is closely related to the life activity of organisms. Soil organisms, according to the degree of connection with their environment, are divided into three main groups:
Geobionts are permanent inhabitants of the soil, their entire development cycle takes place in the soil (earthworms);
Geophiles are animals that part of their development cycle takes place in the soil. These include most insects: locusts, mosquitoes, centipedes, beetles, etc.;
Geoxenes are animals that sometimes visit the soil for temporary shelter or shelter (cockroaches, rodents, mammals living in burrows).
Based on size and degree of mobility, soil inhabitants are divided into groups:
Microbiota – soil microorganisms that form the main link of the detrital food chain (green and blue-green algae, bacteria, fungi, protozoa);
Mesobiota - relatively small mobile animals, insects, earthworms and other animals, including burrowing vertebrates;
Macrobiota – large, relatively mobile insects, earthworms and other animals (burrowing vertebrates).
The top layers of soil contain a mass of plant roots. In the process of growth, death and decomposition, they loosen the soil, creating a certain structure, and at the same time conditions for the life of other organisms. The number of organisms in the soil is huge, however, due to the smoothness of environmental conditions, they are all characterized by “evenness of group composition”, in addition, they are characterized by repeatability in different climatic zones.
Another, directly opposite way of survival of organisms is associated with maintaining a constant internal environment, despite fluctuations in the influence of external factors. For example, birds and mammals maintain a constant temperature inside themselves, which is optimal for biochemical processes in the cells of the body. Many plants are able to tolerate severe droughts and grow even in hot deserts. Such resistance to the influence of the external environment requires large amounts of energy and special adaptations in the external and internal structure of organisms.
In addition to submission and resistance to the influence of the external environment, a third method of survival is possible - avoiding unfavorable conditions and actively searching for other, more favorable habitats. This path of adaptation is available only to mobile animals that can move in space.
All three methods of survival can be combined in representatives of the same species. For example, plants cannot maintain a constant body temperature, but many of them are able to regulate water metabolism. Cold-blooded animals are subject to unfavorable factors, but can also avoid their effects.
Thus, the main ways for organisms to survive when conditions deteriorate are either a temporary transition to an inactive state, or maintaining activity with additional energy expenditure, or avoiding an unfavorable factor and changing habitats. Each species implements these methods in its own way.
conclusions
Thus, the main levels of organization of living systems are distinguished from the molecular to the biosphere, where each level is characterized by a certain set of properties and ecology studies starting from the organismal level. Living organisms have the inherent property of being able to reproduce themselves, as well as adaptability to environmental conditions. The environment of each organism is composed of many elements of inorganic and organic nature.
Control questions
1. What levels of biological organization are the objects of study of ecology?
2. What is a habitat and what environments are inhabited by organisms?
3. Why should we talk about the dependence of living beings not only on the environment, but also about their influence on it?
4. What contributes to the survival of a species?
5. List the main habitats?
6. Why do some organisms fall into a state of suspended animation? What is the ecological meaning of this process?
State autonomous institution
Kaliningrad region
Professional educational organization
"College of Service and Tourism"
COURSE WORK
According to MDK 0n.0n.____________________ __
On this topic ________________________
Is done by a student _________________
(Full Name)
Group ______________________
(group number)
Training program for mid-level specialists in the specialty _
(code and name of specialty)
Coursework supervisor:
(position, full name)
Mark ___________________________
Kaliningrad 2015
INTRODUCTION……………………………………………………………………………….…2
1. Interaction of the human body with the environment………………....3
1.1. Basic human functional systems. The connection between the vital functions of the human body and the environment. The influence of the environment on human performance………………………………………………………3
1.2. The main parameters that determine the production environment (working conditions) in enclosed spaces and their impact on the human body……….5
1.3. The influence of the production environment on labor intensity and the use of working time………………………………………………………...7
1.4. Proposals for improving the environment at work.......9
2. Combustion and fire hazard of substances and industries……………………….......11
2.1. Basic concepts. Physico-chemical principles of combustion…………........11
2.2. Properties of substances characterizing their fire hazard………….13
2.3. General fire safety requirements for production facilities…………………………………………………………………………………..16
2.4. The procedure for analyzing the fire hazard of a production facility and calculating fire risk…………………………………………………………………………………..17
2.5. Classification of basic fire prevention measures. Fire extinguishing agents…………………………………………………………………………………...23
INTRODUCTION
A person is in constant relationship with the environment, which determines his behavior in a given situation. Moreover, not only the environment influences a person, but the individual himself influences it, changing and thereby adapting it to himself.
Life safety is aimed at ensuring favorable living conditions for people, their activities, protecting people and their environment from the effects of external, internal and dangerous factors.
Intensive use of natural resources and the introduction of scientific and technological progress are accompanied by the spread of various natural, biological, man-made, environmental and other hazards. Potential danger is a universal property in the process of human interaction with the environment.
In order for a person to feel comfortable, conditions for his life are necessary in which he feels safe. This can be achieved by establishing an inextricable relationship between man and his environment.
The purpose of the work is to consider the following issues:
Interaction of the human body with the environment;
Combustion and fire safety of substances and industries;
Ventilation and its purpose. Air exchange rate. Calculation method.
Interaction of the human body with the environment
1.1. Basic human functional systems. The connection between the vital functions of the human body and the environment. The influence of the environment on human performance. The human environment is a set of objects, phenomena and factors of the surrounding (natural and artificial) environment that determine the conditions of his life. One of the goals facing this system is security, i.e. not causing harm to human health. Achieving the safety of the “man-environment” system is possible only if the characteristics of each element included in this system are systematically taken into account.
Characteristic “man-environment” systems: domestic, industrial, urban, natural environment.
The natural environment is factors of purely natural, or natural-anthropogenic systemic origin. The natural environment is a complex and diverse combination and interaction of the lithosphere, atmosphere, hydrosphere and biosphere as a whole.
With the advent of industry and transport, the problem of maintaining the purity of the atmosphere, the pollution of which is of natural and artificial origin, arose. The main and most dangerous sources of air pollution are industrial, transport and household emissions. In the atmospheric air, and primarily in the air of industrial centers and cities, as a result of complex chemical reactions of a mixture of gases flowing in its lower layers, various substances are formed that accumulate in a toxic fog - “smog”. This phenomenon is associated with a deterioration in people's well-being, the occurrence of influenza epidemics, and a sharp increase in the number of pulmonary and cardiovascular diseases.
In addition, the ozone layer, which is a protective screen against ultraviolet radiation, is destroyed in the atmosphere. This occurs due to the penetration into the atmosphere of so-called freons, used in the form of aerosols, solvents, etc. both at home and at work. In addition, there is a global increase in temperature on the planet due to the “greenhouse effect”, because... The content of carbon dioxide and methane in the atmosphere is growing rapidly.
All these and other changes occur due to the fault of man, in the process of his industrial and other activities. Currently, a number of countries are trying to combat this problem.
Another important component of the natural environment is the hydrosphere. Humanity is not threatened by water shortages. He is facing a lack of clean water. The main sources of pollution are industrial and municipal sewage drains, washing away from the fields of part of the soil containing various agrochemicals, etc.
All objects of the living world can be divided into plants and animals. The role of vegetation in people’s lives is great (the forest releases oxygen and absorbs carbon dioxide, people eat plants, etc.). But there are many threats to this component (fires, pollution by industrial waste, etc.). The fauna represents an important part of the biosphere of our planet, but the number of fauna is currently declining, which cannot but affect the existence of humanity.
Most of a person’s active life time is occupied by purposeful professional work, carried out in a working environment, which, if accepted regulatory requirements are not met, can adversely affect his performance and health.
Efficiency is the amount of functional capabilities of the human body, characterized by the quantity and quality of work performed in a certain time. During work, the body's performance changes over time.
The production environment is part of the human environment, including natural and climatic factors associated with professional activities (noise, vibration, dust, etc.), called harmful and dangerous. Exposure to negative factors in the working environment leads to injuries and occupational diseases of workers. The most hazardous professions in the national economy include (%): driver (18.9), tractor driver (9.8), mechanic (6.4), electrician (6.3), gas fitter (6.3), gas electric welder (3 ,9), handyman(3.5).
Human labor activity and the production environment are constantly changing in the process of intensive use of the products of scientific and technological progress and the implementation of broad socio-economic transformations.
The intensive growth of cities in the twentieth century, the concentration of the bulk of the population in areas saturated with industrial enterprises, transport routes, and residential buildings, gave rise to a number of problems, including the general problem of human security. In cities, especially large ones, a number of environmentally hazardous industrial production and energy facilities are concentrated, an integral part of which are: powerful emissions of waste into the environment; thermal, electromagnetic, noise pollution; potential danger of large-scale man-made accidents, etc.
Currently, road transport has become the most dangerous for humans. Its victims are not only drivers and passengers, but also pedestrians. Other modes of transport are also dangerous. In the list of emergency situations, fires occupy the leading position in terms of frequency of occurrence and the amount of material damage caused. At the same time, methods of combating and protecting against them are developed carefully and systematically. In Russia, modern methods of ensuring life safety are reflected in legislative acts in all areas of human activity.
Based on all of the above, we can conclude that basically a person creates a threat to his own life and activity.
1.2. The main parameters that determine the production environment (working conditions) in enclosed spaces and their impact on the human body
Any type of work activity is a complex complex of physiological processes, which involves all organs and systems of the human body. In order for a person to feel comfortable during the production process, which means his performance is increased, it is necessary that his working conditions comply with basic standards and requirements. General safety requirements for production equipment and production processes are established by GOST 12.2.003-91 and GOST 12.3.002-75. The safety of production processes is mainly determined by the safety of production equipment.
Most often, a person works indoors, and his working conditions must meet certain parameters. Including the factors of harmfulness. It is very important to maintain the body's thermal balance. The industrial microclimate depends on the climatic zone and season of the year, the nature of the technological process, the type of equipment used, the size of the premises and the number of workers, heating and ventilation conditions.
Standard indicators of industrial microclimate are established by GOST 12.1.005-88 and SanPiN 2.2.4.584-96.
Optimal and acceptable microclimatic conditions must be created in the working area of production premises. This is achieved through industrial ventilation (natural and artificial).
A factor affecting the human body, and, accordingly, the quality of performance of a production task, is lighting. With proper lighting of the work area and production premises, the number of accidents decreases and labor productivity increases. Deviations in lighting harm the health of workers, can cause diseases (for example, myopia), are fraught with a decrease in mental and physical performance, and an increase in the number of errors in production processes. Lighting can be natural or artificial. When organizing industrial lighting, you should ensure a uniform distribution of brightness on the working surface and surrounding objects. The organism surrounding the production environment.
Chemicals and synthetic materials used irrationally in production conditions pose a great danger. Vapors, gases, liquids, aerosols, compounds in contact with the human body can cause diseases or health problems. Exposure to harmful substances on humans can be accompanied by poisoning and injury. At work, toxic substances enter the human body through the respiratory tract, gastrointestinal tract and skin. Maximum permissible concentrations of harmful substances in the air of the working area are regulated by GOST 12.1.005-88 and GN 2.2.5.686.
Another important hazard factor is mechanical vibrations: vibration, noise, infrasound, ultrasound. All these physical processes are associated with the transfer of energy, which, at a certain magnitude and frequency, can have an adverse effect on a person: cause various diseases, create additional dangers. There are several types of vibration, depending on each of them the consequences of this factor are different. When general vibration affects the body, the musculoskeletal system, nervous system and analyzers such as vestibular, visual, and tactile are affected. Local vibration causes spasms of the blood vessels of the hand and forearms, associated with a disruption in the blood supply to the extremities. At the same time, vibrations act on nerve endings and muscle bone tissue. Noise, infrasound and ultrasound are classified as acoustic vibrations, which can be either audible or inaudible. Intense noise in production leads to a decrease in attention and an increase in the number of errors when performing work. Due to noise, labor productivity decreases and the quality of work deteriorates. The entire human body is exposed to noise: it depresses the central nervous system, causes changes in the rate of breathing and pulse, contributes to metabolic disorders, the occurrence of cardiovascular diseases, stomach ulcers, etc. Infrasound is classified as vibrations inaudible to humans. In production conditions, infrasound, as a rule, is combined with low-frequency noise, and in some cases with low-frequency vibration. When the body is exposed to infrasound with a level of 110 to 150 dB, unpleasant subjective sensations and functional changes may occur: disturbances in the cardiovascular and respiratory systems, the central nervous system, and the vestibular analyzer.
1.3. The influence of the production environment on labor intensity and use of working time
Human labor activity and the environment are constantly changing in the process of accelerating scientific and technological progress and the implementation of broad socio-economic transformations. At the same time, labor remains the first, basic and indispensable condition of human existence. Various forms of labor activity are divided into physical and mental labor.
Physical labor is characterized primarily by an increased load on the musculoskeletal system and its functional systems (cardiovascular, neuromuscular, respiratory, etc.) that support its activity.
Mental work combines work related to the reception and processing of information, which requires the primary tension of the sensory apparatus, attention, memory, as well as the activation of thinking processes and the emotional environment.
Currently, there are several main forms of labor that require a certain intensity of labor and the use of working time.
1. Forms of labor that require significant muscle energy.
Strenuous physical labor, which stimulates the development of the muscular system and metabolic processes, at the same time has a number of disadvantages. The main one is inefficiency associated with low labor productivity and the need for breaks to restore physical strength, amounting to up to 50% of working time.
2. Mechanized forms of labor.
Mechanization of labor makes it possible to reduce the nature of muscle loads and complicate action programs. However, the monotony of simple actions and the small amount of information perceived in this process lead to monotony of work.
3.Forms related to automated production.
With automated forms of labor, the employee is required to be constantly ready for action and quick to react, which is necessary for the timely elimination of problems that arise.
4. Group forms of labor - conveyor, the distinctive feature of which is the division of the general process into specific operations, the strict sequence of their implementation, the automatic supply of parts to each workplace using a conveyor belt.
One of the negative consequences of assembly line work is monotony, which is expressed in premature fatigue and nervous exhaustion.
5. Forms of labor associated with the management of production processes and mechanisms (mental labor).
Intellectual work consists of processing and analyzing a large volume of varied information, and therefore requires the mobilization of memory, attention, tension of the sensory apparatus, and activation of thinking processes. Muscle loads are insignificant.
Intellectual work is characterized by hypokinesia, i.e. a significant decrease in a person’s motor activity, leading to a weakening of the body’s reactivity and increased emotional stress.
1.4.Proposals for improving the industrial environment
To increase a person’s performance, you need to create comfortable conditions for him in the workplace, no matter what work he does. For example, to protect a person from mechanical injuries, it is necessary either to prevent him from entering hazardous areas, or to build special devices that protect people from a dangerous factor.
To ensure safe and reliable operation of equipment, it is very important to install information, warning, emergency automatic control and alarm devices.
It is very important to properly organize the workplace for those who work on personal computers. To do this, it is necessary that the room be sufficiently spacious, well ventilated, and properly lit. You cannot work on a computer in a dark or semi-dark room.
In addition, a person, working at a computer, moves very little, which negatively affects his health. In such organizations, you can organize, for example, a “sports day” twice a month (go to the gym, pool, etc.). In my opinion, this will relieve the employee emotionally and maintain physical fitness, which will only have a positive impact on his performance and efficiency in completing assigned tasks.
In production, to protect workers from harmful emissions and emissions, it is necessary to install various filters to reduce their concentrations in the ambient air. To protect against harmful discharges of the hydrosphere, methods such as rational placement of discharge sources and organization of water intake and drainage are used; diluting harmful substances in water bodies to acceptable concentrations, and also using wastewater treatment means (mechanical, physico-chemical, biological methods).
It is very important to learn how to protect the environment from waste generated from industrial and other industries. To do this, it is necessary to introduce technologies for waste collection and disposal. Including waste recycling, which will ensure minimal environmental pollution. The most effective solution to the problems of protection from industrial waste is possible with the widespread introduction of low-waste technologies.
"Organism and Environment"
Introduction
In the process of evolution and intense struggle for existence, organisms mastered a wide variety of environmental conditions, and at the same time, the entire modern diversity of plants and animals was formed, which amounts to approximately two million species. In turn, the vital activity of organisms had a tremendous impact on the inanimate environment, which became more complex and evolved along with the development of life.
The overall picture of the nature around us is not a chaotic combination of various living beings, but a fairly stable and organized system in which each type of plant and animal occupies a certain place.
We know that any species is capable of unlimited reproduction and can quickly populate all the space available to it. It is obvious that the simultaneous coexistence of various living beings is possible only if there are special mechanisms that regulate the course of reproduction and determine the spatial distribution of species and the number of individuals. Such regulation is a consequence of complex competitive and other relationships between organisms in the process of their life. Influences from the physical conditions of the environment also play a major role.
The study of the relationships of organisms with each other and between organisms and the physical environment constitutes the content of a section of biology called ecology (“oikos” - home, shelter and “logos” - science, Greek).
Ecology relies on generalizations and conclusions from most other branches of biology, as well as the Earth sciences.
Ecological laws serve as a scientific basis for the rational use of natural biological resources by humans and for solving many economic problems.
1. Environment and environmental factors
Organism and environmental factors. The concept of external environment includes all conditions of living and inanimate nature that surround the organism and directly or indirectly affect its condition, development, survival and reproduction. The environment is always a complex complex of various elements. Individual elements of the environment that act on the body are called environmental factors.
Among them, two groups of different nature are distinguished:
1. Abiotic factors - everything elements of inanimate nature that affect the body. The most important factors include light, temperature, humidity and other climate components, as well as the composition of the water, air and soil environment.
2. Biotic factors- all kinds of influences that the body experiences from the living beings around it. In the modern era, human activity has an extremely large impact on nature, which can be considered as a special environmental factor.
In nature, external conditions are always changeable to some extent. Each species in the process of evolution has adapted to a certain intensity of environmental factors and the amplitude of their fluctuations. The resulting adaptations to specific living conditions are hereditarily fixed. Therefore, while being very appropriate for the environment in which the species was historically formed, ecological adaptations limit or even exclude the possibility of existence in a different environment.
Various environmental factors: temperature, gas composition of the atmosphere, food, act on the body in different ways. Accordingly, the morphological and physiological adaptations to them are different. However, the results of the influence of any factor are ecologically comparable, since they are always expressed in a change in the viability of the organism, which ultimately leads to a change in population size.
The intensity of the factor that is most favorable for life is called optimal or optimum. The more the factor value deviates from the optimal value for a given type (both downward and upward), the more vital activity is inhibited. The limits beyond which the existence of an organism is impossible are called the lower and upper limits of endurance.
Since the optimum reflects the characteristics of conditions in habitats, it is usually different for different species. In accordance with which level of the factor is most favorable, it is possible to distinguish between species: heat- and cold-loving, moisture- and dry-loving, adapted to high and low salinity of water, etc. Along with this, species adaptations are also manifested in tolerance to the degree of variability factor a. Species that tolerate only small deviations of the factor from the optimal value are called narrowly adapted; widely adapted - species that can withstand significant changes in a given factor. For example, most sea inhabitants are narrowly adapted to relatively high salinity of water, and a decrease in the concentration of salts in water is detrimental for them. Inhabitants of fresh waters are also narrowly adapted, but to a low salt content in the water. However, there are species that can tolerate very large changes in water salinity, for example, the three-spined stickleback fish, which can live in both fresh waters and salt lakes and even in the seas.
Adaptations to individual environmental factors are largely independent, so the same species may have a narrow adaptation to one of the factors, for example, salinity, and a broad adaptation to another, for example, temperature or food.
Interaction of factors. Limiting factor. The body is always simultaneously affected by a very complex set of environmental conditions. The result of their joint influence is not a simple sum of reactions to the action of individual factors. The optimum and limits of endurance in relation to one of the environmental factors depend on the level of others. For example, at an optimal temperature, tolerance to unfavorable humidity and lack of food increases. On the other hand, the abundance of food increases the body's resistance to changes in climatic conditions.
However, such mutual compensation is always limited, and none of the factors necessary for life can be replaced by another. Therefore, when changing habitats or changing conditions in a given area, the life activity of a species and its ability to compete with others will be limited by the factor that deviates most strongly from the optimal value for the species. If the quantitative value of at least one of the factors goes beyond the limits of endurance, then the existence of the species becomes impossible, no matter how favorable the other conditions are.
For example, the distribution of many animals and plants to the north is usually limited by a lack of heat, while in the south the limiting factor for the same species may be a lack of moisture or essential food.
Interdependence of organisms and environment. The organism is entirely dependent on the environment and is unthinkable without it. But in the process of life activity and continuous exchange of substances with the environment, plants and animals themselves influence the surrounding conditions and change the physical environment. The changes that arise in it, in turn, cause organisms to need new ecological adaptations. The scale and significance of such changes in inanimate nature under the influence of the activities of living beings are very great. Suffice it to remember that plant photosynthesis led to the formation of a modern atmosphere rich in oxygen, which has become one of the main conditions of existence for most modern organisms. As a result of the vital activity of organisms, soil arose, to the composition and nature of which plants and animals adapted in the process of evolution. The climate also changed, and local features emerged - microclimates.
2. Main climatic factors and their influence on the body
Climate is one of the main components of the external environment. For the life of terrestrial plants and animals, 3 climate elements are of greatest importance: light, temperature and humidity. An important feature of these factors is their natural variability both throughout the year and day, and in connection with geographic zoning. Therefore, adaptations to them have a natural zonal and seasonal character.
Light. Solar radiation serves as the main source of energy for all processes occurring on Earth. The biological effect of solar radiation is diverse and is determined by its spectral composition, intensity, as well as daily and seasonal frequency of illumination.
In the spectrum of solar radiation, three regions are distinguished, different in biological action: ultraviolet, visible and infrared.
Ultraviolet rays with a wavelength less than 0.290 µm destructive for all living things. Life on Earth is possible only because this short-wave radiation is blocked by the ozone layer of the atmosphere. Only a small portion of longer ultraviolet rays reaches the Earth's surface (0.300-0.400 µm). They are highly chemically active and in large doses can damage living cells. In small doses, ultraviolet rays are necessary for humans and animals. In particular, they contribute to the formation of vitamin D in the body. Some animals, such as insects, visually distinguish ultraviolet rays.
Effect of visible rays with a wavelength of about 0.400 to 0.750 µm, which account for most of the energy of solar radiation reaching the earth's surface, led to the emergence of a number of very important adaptations in plants and animals.
Green plants synthesize organic matter, and therefore food for all other organisms, using the energy of this particular part of the spectrum.
Still, for animals and non-chlorophyll plants, light is not a prerequisite for existence, and many soil, cave and deep-sea species have adapted to life in the dark. For most animals, visible light is one of the important environmental factors. It is a strong irritant and takes part in the regulation of many processes. The role of visible light in behavior and spatial orientation is especially important. Even many single-celled animals clearly respond to changes in light. More highly organized ones, starting with coelenterates, already have special light-sensitive organs, and higher forms (arthropods, mollusks, vertebrates) have developed in parallel and independently complex organs of vision - eyes and the ability to visually perceive surrounding objects.
Most animals are good at distinguishing the spectral composition of light, that is, they have color vision. The development of vision has led to the appearance of various colors in animals, which help them hide from enemies or recognize individuals of their own species. Plants evolved brightly colored flowers to attract pollinators, making cross-pollination easier.
Infrared rays with a wavelength greater than 0.750 µm, not perceived by the human eye, are an important source of thermal energy. They are especially rich in direct sunlight. These long-wave radiations, absorbed by the tissues of animals and plants, cause them to heat up. Many cold-blooded animals (lizards, snakes, insects) use sunlight to increase their body temperature, actively choosing the most sunlit places. The light regime in nature has a distinct daily and seasonal periodicity, which is determined by the rotation of the Earth.
Due to the daily rhythm of lighting, animals have developed adaptations to a daytime and nocturnal lifestyle. Each species is active at certain times of the day. At certain times of the day, the flowers of many plants open, and some exhibit diurnal leaf movements (for example, some legumes). Almost all internal physiological processes in plants and animals have a daily rhythm with maximum and minimum at certain hours.
The length of the day is of great ecological importance. It varies greatly with latitude and time of year. Only at the equator the length of the day is the same all year round and is equal to 12 hours. With distance from the equator, the length of the day in the summer half of the year progressively increases, and in the winter half of the year it decreases; the longest day is on June 22 (summer solstice) and the shortest day is on December 22 (winter solstice). Beyond the Arctic Circle there is continuous day in summer and continuous night in winter, the duration of which at the poles reaches 6 months. On the days of the spring (March 21) and autumn (September 23) equinox, the length of the day between the polar circles is 12 hours everywhere. The influx of solar radiation onto the earth's surface depends on the length of the day and the height of the Sun above the horizon, therefore temperature conditions are closely related to seasonal changes in the light regime. As a result, the length of the day serves as an important ecological factor regulating periodic phenomena in wildlife.
Temperature. All chemical processes occurring in the body depend on temperature. It is natural, therefore, that large changes in thermal conditions, which are often observed in nature, deeply affect the growth, development and other manifestations of the life of animals and plants. The dependence on external temperature is especially clear in organisms that are unable to maintain a constant body temperature, that is, in all plants and most animals, except birds and mammals. The vast majority of terrestrial plants and animals in a state of active life cannot tolerate negative temperatures.
The upper temperature limit of development varies for different species, but rarely exceeds 40-45°C. Only a few species have adapted to life at very high temperatures. Thus, in hot springs, some mollusks live at water temperatures up to 53°C, fly larvae - at 60°C, and some blue-green algae and bacteria live at 70-85°C.
The optimal temperature for development depends on the habitat conditions of the species; for most terrestrial animals it fluctuates within rather narrow limits (15-30°C).
Organisms with an unstable body temperature are called poikilothermic. In them, an increase in temperature causes an acceleration of all physiological processes. Therefore, the higher the temperature, the shorter the time required for the development of individual stages or the entire life cycle. If at 26°C the period from exit from the egg to pupation is 10-11 days, then at a temperature of about 10°C it increases 10 times, i.e. exceeds 100 days. This dependence has a very correct character.
Having established experimentally the duration of development of a given species of animal or plant at different temperatures, it is possible to determine with sufficient accuracy the expected development time in a natural environment. In nature, the temperature always fluctuates and often goes beyond the level favorable for life. This has led to the emergence of special adaptations in plants and animals that weaken the harmful effects of such vibrations. Plants, for example, when overheated, lower the leaf temperature, increasing the evaporation of water through the stomata. Animals can also slightly lower their body temperature by evaporating water through the respiratory system and skin.
The possibility of an active increase in temperature in plants is extremely small, and in poikilothermic animals it is noticeable only in the most mobile species. Thus, in flying insects, due to increased muscle work, the internal temperature can rise above the ambient temperature by 10-20 C or more. In bumblebees, locusts and large butterflies it reaches 30-40°C during flight, but with the cessation of flight it quickly drops to the level of air temperature.
Although poikilothermic organisms exhibit some ability for thermoregulation, it is so imperfect that their body temperature depends mainly on the temperature of the environment. Only some social insects, especially bees, have evolved a more efficient way of maintaining temperature through collective thermoregulation. Each individual bee is not able to maintain a constant body temperature, but tens of thousands of bees that make up a colony produce so much heat that the hive can maintain a constant temperature of 34-35 ° C, necessary for the development of larvae.
Birds and mammals, i.e., warm-blooded animals, have the most advanced thermoregulation. The ability to maintain a constant body temperature is an ecologically very important adaptation, which ensured significant independence of higher animals from the thermal conditions of the environment. Most birds have a body temperature slightly above 40°C, while mammals usually have a slightly lower body temperature. It remains at a constant level regardless of fluctuations in ambient temperature. Thus, at frosts of about -40°C, the body temperature of the arctic fox is 38°C, and that of the white partridge is 43°C, i.e., almost 80°C higher than the environment. In primitive Australian mammals - the platypus and echidna - thermoregulation is poorly developed, and their body temperature is highly dependent on environmental conditions. Thermoregulation is also imperfect in small rodents and the young of most mammals.
For the existence of animals in changing environmental conditions, not only the ability to thermoregulate, but also behavior is of great importance: choosing a place with a more favorable temperature, activity at a certain time of day, building special shelters and nests in a more favorable microclimate, etc. So, in the summer During hot weather, many inhabitants of steppes and deserts hide in holes, under stones, and bury themselves in the sand, avoiding overheating. In spring and autumn, when the temperature is low, the same species choose the warmest, sun-warmed places.
Temperature, as well as the light regime on which it depends, naturally changes throughout the year and in connection with geographic latitude.
At the equator, the temperature, like the length of the day, is very constant and stays at a level close to 25°C all year round. With distance from the equator, the annual temperature amplitude increases. At the same time, summer temperature changes much less with increasing geographic latitude than winter temperature. In summer, the temperature in all points remains within the usual normal range. Consequently, for the existence of animals and plants in the climate of temperate and northern latitudes, the main importance is adaptation not to the temperature conditions of summer, but to the negative temperatures of winter.
Bibliography
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2. Kemp P., Arms K. Introduction to biology. M., 2000.
3. Libbert E. General biology. M., 1978 Llozzi M. History of physics. M., 2001.
4. Naydysh V.M. Concepts of modern natural science. Tutorial. M., 1999.
5. Nebel B. Environmental Science. How the world works. M., 1993.
Living organic matter on Earth, being an extremely active source of specific energy, is at the same time distinguished by an exceptional variety of forms of its manifestation.
The diversity of these forms is the result of the long-term development of the organic world and its adaptation to a geographical environment that varies in time and space.
The organism is inextricably linked with the environment and is unthinkable outside this environment, if only because one of the main manifestations of life (however, not exhausting the qualitative specificity of life processes) is metabolism. Other signs of living things: sensitivity, mobility, growth, development, reproduction, heredity, variability. The existence of any organism consists of the acceptance and accumulation of matter (assimilation) and the release and waste of matter (dissimilation). The environment is the only source of substances from which the organism builds its body. Outside of metabolism, no substance can be formed in the body. The interaction of living bodies with the environment is an indispensable condition for their preservation and existence, as opposed to inanimate bodies, for which interaction with the environment is a condition for their destruction.
Assimilation is the ability of a living thing to perceive, modify and assimilate to itself the substances of the external environment. Animals assimilate mainly substances of organic nature, plants - inorganic. But in both cases, in the process of assimilation, the inanimate turns into the living, the external into the internal. The body constantly builds itself from the substances of the external environment in its own way.
Dissimilation (decay) represents the other side of a single contradictory metabolic process. It serves as a source of energy, due to which biochemical reactions of synthesis (assimilation) and all other manifestations of life activity (movement, etc.) occur, and two types of energy sources predominate: biological oxidation reactions that underlie respiration, and non-oxidative breakdown of mainly carbohydrates , i.e. reactions such as fermentation. An important feature of living matter is that all biochemical reactions in metabolism do not occur in a random, but in a strictly defined sequence, that is, they are ordered in time and connected into an integral system. This ensures, in the presence of ceased decay, the constancy of the composition and structure of the organism.
Metabolism is the basis of all life processes. The connection of an organism with the environment presupposes the conformity of the organism with the conditions of its existence, the adaptation (adaptation) of the organism to the environment. This is observed everywhere in nature, and adaptation covers all the properties and characteristics of organisms - their shape, color, physiological functions, behavior, etc. - and helps the organism to make the best use of the environment, get rid of danger, facilitate an attack on the victim, and ensure only life, but also reproduction.
As a result of what and how did organisms adapt to their environment? What is the motivating reason for the formation and improvement of forms of animals and plants, that is, the reason for the development of the organic world, the transition of simple forms into more complex ones?
Everyday observation and experience indicate that during reproduction, organisms reproduce from generation to generation only their own kind. This biological inertia, the property of offspring to retain the characteristics of their parents, is called heredity. Another property of an organism - its biological plasticity, the ability to change in comparison with its parents - is called variability.
Variability is the result of the influence of the external environment, as well as the result of the correlation between the organs and functions of the body, due to which a change in some entails a change in others. Heredity is defined as the property of a living body to require certain conditions for its life, its development and definitely respond to certain conditions. If an organism finds in its environment and assimilates something that fully meets its requirements, it retains its resemblance to its parents. Minor changes in the environment, within certain relatively narrow limits, do not change the heredity of the organism, since they do not disrupt the general nature of metabolism. However, any serious change in living conditions, caused by the vital activity of the organism itself or a change in the environment, inevitably entails a change in the type of metabolism. Moreover, since there is no life outside metabolism, the organism must either die or adapt to new conditions, that is, change in accordance with these conditions, change its heredity.
By resorting to alteration of organisms, man has long taken advantage of both variability and heredity. The accumulation and creation by man of certain, self-selected characteristics in any animal or plant through the use of variability and heredity is called artificial selection, selection, or breeding. In selection, a very important role is played by a person’s changing the living conditions of the body and changing the type of metabolism.
In a natural environment, of course, the same laws of variability and heredity operate, but here selection is no longer governed by man, but by the struggle for existence, understood in a broad sense as the survival of the fittest. Unlike artificial selection, selection in nature, called natural selection, acts to benefit the organism itself (and not the person).
The inevitability of natural selection follows from the fact that more individuals of a given species are born in nature than the conditions available for their life allow. True, a huge number of embryos and individuals die, regardless of the degree of their adaptation to the environment (eating eggs by predatory fish, death of seeds of land plants that fall into the water, floods, fires and other natural disasters). At the same time, a huge number of individuals that survived natural death remain exposed to many unfavorable conditions of inanimate nature, epidemics, attacks by enemies, and are forced to fight for food, light, space, water (in particular with representatives of their own species, which impose similar demands on the environment ) etc. Under these conditions, only those organisms that have characteristics that provide the organism in the current situation with some advantage for its existence and further reproduction are destined to survive. As a result of variability, heredity and natural selection, varieties arise within a species. Over time, the characteristics of extreme varieties diverge so much that new species are formed from these varieties, and intermediate varieties, as less adapted, die out as a result of natural selection.
Thus, the development of the organic world is adaptive in nature. The variety of forms of living beings is a variety of forms of adaptation, but the adaptation is relative, temporary, having significance only in a certain life situation. The situation changes - the previous fitness loses its meaning.
The organism in itself has no special desire for purposeful change. Purposefulness in the structure, functions and behavior of an organism is a historical result of long-term natural selection, and not at all an original property of living matter.
The adaptation of an organism to its environment is most clearly expressed within the area in which it usually lives. Transferred to another environment, the organism can adapt to it, but the degree and nature of this adaptation largely depend on the biological plasticity of the organism. Some organisms die in a new environment, others live and reproduce, others live but do not reproduce, which practically means that the species to which a given individual belongs is condemned to death in a new environment, since the individual does not leave offspring. Some organisms live by maintaining old habits, while others change these habits. For example, the Australian black swan nests in its homeland in November-December, and in zoos in southern Ukraine in March-April, i.e. in both cases in the spring, but in different months of the year, in accordance with the course of climatic processes in the northern and southern hemispheres.
The doctrine of natural selection can only be applied in biology. It is not a universal methodology of science; it cannot be transferred to human society and the laws of development of this society.
Organism - biological system of the biosphere
Any living creature is body, differing from inanimate nature by a set of certain properties inherent only to living matter - cellular organization and metabolism.
From a modern point of view, the body is a self-organizing energy information system that overcomes entropy (see section 9.2) by maintaining a state of unstable equilibrium.
The study of the relationship and interaction in the “organism-environment” system led to the understanding that living organisms inhabiting our planet do not exist on their own. They are completely dependent on the environment and are constantly affected by it. Each organism successfully survives and reproduces in a specific habitat characterized by a relatively narrow range of temperatures, rainfall, soil conditions, etc.
Therefore, the part of nature that surrounds living organisms and has a direct or indirect effect on them is their habitat. From it, organisms obtain everything they need for life and secrete metabolic products into it. The habitat of each organism is composed of many elements of inorganic and organic nature and elements introduced by man and his production activities. Moreover, some elements may be partially or completely indifferent to the body, others are necessary, and others have a negative effect.
Living conditions, or conditions of existence, is a set of environmental elements necessary for an organism, with which it is in inextricable unity and without which it cannot exist.
Homeostasis - self-renewal and maintaining the constancy of the internal environment of the body.
Living organisms are characterized by movement, reactivity, growth, development, reproduction and heredity, as well as adaptation. During metabolism, or metabolism, a number of chemical reactions occur in the body (for example, during respiration or photosynthesis).
Organisms such as bacteria are capable of creating organic compounds at the expense of inorganic components - nitrogen or sulfur compounds. This process is called chemosynthesis.
Metabolism in the body occurs only with the participation of special macromolecular protein substances - enzymes, acting as catalysts. Enzymes help regulate the metabolic process in the body vitamins and hormones. Together they carry out the overall chemical coordination of the metabolic process. Metabolic processes occur throughout the entire path of individual development of the organism—ontogenesis.
Ontogenesis - a set of successive morphological, physiological and biochemical transformations undergone by an organism over the entire period of life.
The organism's habitat- a set of constantly changing conditions of his life. The terrestrial biota has mastered three main habitats: , and soil, together with rocks of the near-surface part of the lithosphere.