>>Leaf Breath

§ 28. Breathing of a leaf

Organic matter from inorganic green plant forms only in the light. These substances are used by plants for nutrition. But plants do more than just eat. They breathe like all living beings. Breathing occurs continuously day and night. All plant organs breathe. Plants breathe oxygen and emit carbon dioxide, just like animals and humans.

Experience allows you to make sure that the plant breathes. Let's take a branch of a plant that has at least 10-12 leaves. Instead of a twig, you can take several leaves of geranium or primrose with long petioles. Or put the sprig in a glass of water. Place the glass on a plate, next to which we place another glass with clear lime water. Then we will close it all with a glass cap or a large glass jar and place it in a dark cabinet. 55 . In the dark, plants, as you already know, cannot produce oxygen. In a dark closet, plant leaves will only breathe, which means they will absorb oxygen and release carbon dioxide. The carbon dioxide released by the leaves will cause lime water poured into a glass to become cloudy. The breathing of leaves does not stop even in the light, since plants, like animals and humans, breathe around the clock - both in the light and in the dark.

This means that in the light two opposite processes occur in the plant. One process - photosynthesis, the other is breathing. During photosynthesis, organic substances are created from inorganic substances and energy from sunlight is absorbed. During respiration, organic substances are consumed in the plant, and the energy necessary for life is released. In the light in progress photosynthesis Plants absorb carbon dioxide and release oxygen. Along with carbon dioxide, plants in the light absorb oxygen from the surrounding air, which plants need for respiration, but in much smaller quantities than they release during the formation of sugar. Plants absorb much more carbon dioxide during photosynthesis than they release during respiration. Ornamental plants in a room with good lighting emit significantly more oxygen during the day than they absorb in the dark at night.

Lesson content lesson notes supporting frame lesson presentation acceleration methods interactive technologies Practice tasks and exercises self-test workshops, trainings, cases, quests homework discussion questions rhetorical questions from students Illustrations audio, video clips and multimedia photographs, pictures, graphics, tables, diagrams, humor, anecdotes, jokes, comics, parables, sayings, crosswords, quotes Add-ons abstracts articles tricks for the curious cribs textbooks basic and additional dictionary of terms other Improving textbooks and lessonscorrecting errors in the textbook updating a fragment in a textbook, elements of innovation in the lesson, replacing outdated knowledge with new ones Only for teachers perfect lessons calendar plan for the year; methodological recommendations; discussion program Integrated Lessons

PLANTS AND MICROECOLOGY OF HOUSING

“Man is historically more adapted to life in rural areas, so the urban environment causes stress in him,” noted Professor N. F. Reimers.

The danger to humans of modern anthropogenic influences is caused by their fundamental difference from natural influences that acted for hundreds of thousands of years during the period of human formation. Therefore, it is very important, when considering various methods for eliminating harmful environmental factors, to pay attention to living nature.

Creating a harmonious living space using methods of working with indoor plants and video ecology.

Improving the habitat by releasing biologically active plant substances into the air

Phytoncides

Phytoncides (from the Greek - “plant kills”) are volatile organic substances of plants that have a pronounced antimicrobial effect.

The term was introduced in 1928 by B.P. Tokin in order to emphasize the ability of higher plants to protect themselves from pathogenic microorganisms - microbes, molds and protozoa. Initially, in the experiments of Tokin and his followers, the protistoncidal (protozoan-killing) effect of phytoncides was discovered. Later, with the works of N. G. Kholodny, A. A. Chesovennaya and others. It has been proven that phytoncides have an important role in allelopathy, i.e. in the chemical interaction of plants in phytocenoses. The work of Soviet scientists has proven that absolutely all plants have the ability to secrete phytoncides. Considering that the amount and activity of phytoncides in the same species varies depending on the conditions of the place of growth, and also that different plants have different phytoncides. Phytoncides increase the degree of air ionization and also neutralize industrial toxins in the air and soil.

The chemical nature of phytoncides is complex and still little studied. It has been established that phytoncides, as a rule, are a mixture of various substances, among which are identified: essential oils, aldehydes, hydrocyanic acid, etc.

The biological activity of phytoncides is, as a rule, determined not by one particular substance, but by the entire set of substances. There are: volatile fractions of phytoncides, phytoncidal properties of tissue juices.

Effect of phytoncides on human health and the environment

Scientists have calculated that the Earth's plants annually release into the atmosphere about 490 million tons of phytoncides, volatile substances that kill or suppress the growth and development of microorganisms. Each of us has been convinced more than once how biologically active they are by bringing a bouquet of strong-smelling flowers into the house. The aroma of lilies, lilies of the valley or bird cherry can cause very unpleasant painful sensations even in the healthiest heads after a few hours. These substances, at least in strong concentrations, are even worse for animals. Chopped bird cherry leaves placed under a glass cover with a fly, mouse or even a rat can kill the animal after a while.

Essential oils

Essential oils are volatile aromatic liquids of complex chemical composition (more than 100 components), the main components of which are terpenoids. There is practically no essential oil about which one could say that its composition has been fully studied.

Essential oils contain a mixture of various organic substances, both liquid and crystalline, easily soluble in each other. Essential oils isolated from plants are colorless or slightly yellowish oily liquids with a peculiar odor.

Essential oils are similar in appearance to fatty oils, although their chemical composition has nothing in common with them. They are called essential because of their volatility. Thus, the name “essential oils” is purely conventional and is only traditional and generally accepted.

The pleasant smell of lily of the valley, jasmine, rose, lilac, mint, dill and other plants is associated with the presence of essential oils.

Essential oils are found in plants of various families: Lamiaceae, Cloves, Asteraceae, Umbelliferae, and conifers. They are formed in various organs: flowers, fruits, leaves, roots, stems. Essential oils of even one plant can be different in composition in different organs, and therefore in smell. The varied effects of these products depend on their chemical composition.

The effect of essential oils on human health and mood

Due to differences in chemical composition, essential oils have different effects on the body: antimicrobial (bactericidal), antispasmodic, anti-inflammatory, expectorant, improves the secretion of digestive juices, etc. Some essential oils have an effect on the cardiovascular and nervous system.

The influence of the smells of essential oils on a person’s feelings and mood, the occurrence of one or another psychological reaction, has been noted. This is due to a subconscious reaction to olfactory receptors. Scientists Kirk-Smith and Booth argue that most human reactions to odors are associative in nature. Events and sensations at different periods of life took place under certain conditions, including smell. As a result, they became associated with that smell and were remembered.

Some phytoncidal and essential plants

Lavender. Lavender essential oil has phytoncidal properties. It has a detrimental effect on streptococci, staphylococci, E. coli, tuberculosis bacillus, and influenza virus. Lavender acts as a general strengthening plant and increases the body's resistance to adverse conditions. Phytoncides have a beneficial effect on a person’s mood, calm the nervous system and improve sleep, so this plant is useful for people with great mental stress and stress.

Rosemary. Rosemary improves the health of people with chronic bronchitis and bronchial asthma and vegetative-vascular distance. Increases tone during mental fatigue, reduces headaches and normalizes blood pressure. Essential oil has antiseptic properties and is useful for colds and inflammatory diseases.

Myrtle. It has antiseptic properties, significantly reducing the number of microorganisms in the air (up to 50% within a radius of 5 m). Reduces the incidence of respiratory tract diseases, acute respiratory infections, acute respiratory viral infections, and influenza.

Lemon. The phytoncidal field of lemon is quite large, up to 7 m, and is quickly restored after ventilation, so this plant can be used for large rooms contaminated with mold fungi and opportunistic microorganisms. Reduces the number of colds, useful for hypertension.

Coniferous indoor plants. All coniferous plants are strong antiseptics. There are types of coniferous plant varieties adapted to indoor conditions. Among them are cypress trees, cypress trees, cedar, juniper, etc. They are often grown as bonsai and therefore are highly decorative.

Among coniferous plants, juniper is the most phytoncidal active. It produces about 6 times more phytoncides than other conifers. However, it is very sensitive to chemical air pollutants.

Geranium (pelargonium). Geranium essential oil helps calm the nervous system, improves sleep and reduces stress. Useful for colds. The phytoncidal properties are not very strong, however, in the presence of geranium, the number of colonies of protozoan microorganisms is reduced by approximately 46%. It is recommended to grow geranium in spacious rooms so that the concentration of essential oils and phytoncides in the air is not too high.

Citronella. The plant has antiseptic properties and is useful for inflammatory diseases. It has a tonic and stimulating effect on nervous disorders that arise as a result of stress.

Absorption of toxic substances from the air

Under the influence of compounds included in phytoncides, the concentration of some dangerous pollutants in the air is reduced: carbon monoxide by 10 - 30%, sulfur dioxide by 50 - 70%, nitrogen oxides by 15 - 30%.

Plants “feed” on polluted air, releasing “fresh” oxygen. For example, one 1.5-meter shefflera absorbs about 10 liters of carbon dioxide per day, releasing 2 - 3 times more oxygen. Pollution is neutralized not only by leaves, but also by soil in pots. And the more it is loosened, the better the air is purified.

Plants that absorb harmful substances from the air

Chlorophytum. Absorbs formaldehyde, carbon monoxide, benzene, ethylbenzene, toluene, xylene from the air. Significantly reduces colonies of microorganisms in the air. Particularly active against mold fungi.

Grows well in apartments, is not afraid of dry air, and is unpretentious to light.

Dieffenbachia. Cleans the air from toxins coming from roads; absorbs formaldehyde, xylene, trichlorethylene, benzene. A highly decorative plant, it has a wide variety of shapes and colors.

Dracaena. Absorbs benzene, xylene, trichlorethylene, formaldehyde from the air.

Sansevieria. Absorbs benzene, formaldehyde, trichlorethylene from the air.

Spathiphyllum. Absorbs benzene, formaldehyde, phenol, and toluene from the air.

A highly decorative plant, it has various sizes and can be grown in any room.

Aloe. Absorbs formaldehyde from the air. Significantly reduces the number of protozoan microorganisms in the air (up to 3.5 times). Weak effect on opportunistic microorganisms.

It is a valuable medicinal plant used in the treatment of gastritis, enterocolitis, peptic ulcers, purulent wounds, burns, inflammatory diseases of the mucous membrane, stomatitis.

Peperomia. Absorbs formaldehyde from the air.

Increasing beneficial ionization and air humidity with indoor plants

All plants help increase beneficial ionization and air humidity. By releasing water through their leaves, plants humidify the air. Most of them return up to 90% of moisture to the environment, using only 10 percent for their needs. Plants that give off a lot of moisture include: dwarf ficus, fatsia, parmannia, dracaena, nephrolepis, hibiscus.

By evaporating water, plants are able to reduce air temperature in summer by 8 - 25 degrees, increase its humidity and soil moisture by 10 - 20% and 10%, respectively. Moreover, one hectare of plantings humidifies the air 10 times more than the water surface of the same area.

Plants that increase humidity and air ionization.

Nephrolepis. Increases air humidity. It is highly decorative and can be used in the interior for single placement.

Fatsia. The plant reaches 1.4 m in height and is hardy. Can be used in interiors for single occupancy.

Cyperus. It moisturizes the air well and has phytoncidal properties.

Sparmannia. Increases air humidity

Fast-growing, highly decorative, has light pubescent leaves that harmonize well with the dark leathery leaves of philodendrons and ficuses.

Improved visual environment

A beautiful city, well perceived by residents and positively influencing them, is a harmonious city, in harmony with nature and based on knowledge and consideration of the laws of nature.

Beauty is harmony achieved by a combination of various details. Interestingly, a harmonious combination of artificial structures and nature is impossible if geometric forms of strictly functional architecture are used. Strictly ordered urban space is not in harmony with the space of natural landscapes.

The main condition for the harmony of buildings with the landscape is the preservation and development of the plastic properties of the site - the plastic integrity and originality of its relief and green forms.

The aesthetic role of indoor plants and the formation of a comfortable visual environment

In addition to the functional features of the landscape, its aesthetic properties are very important. The beauty of the landscape has a strong emotional impact on a person, raising his vitality.

There are two fundamentally different approaches to plant maintenance. The first approach treats plants like pets and places them individually in their appropriate environment. The second approach considers plants as living decorations designed to make the room more welcoming. Therefore, when choosing indoor plants, it is very important to take into account not only the characteristics of the room, its size, design style, but also the psychological characteristics of the people living or working.

To create harmonious interior compositions from indoor plants, you can use the following recommendations:

• large plants should be placed in spacious rooms, small pots on small window sills;
• a spectacular plant looks better alone, nondescript ones should be placed in groups;
• plants with brightly colored variegated leaves are best used as single plants;
• hanging plants can be grown in compositions with other plants in hanging baskets or on high tables;
• For most plants, a simple wall of any pastel color is a good background;
• variegated plants and pale flowers look better against a dark background;
• small plants get lost against the background of wallpaper with a large pattern.

Some ornamental plants

Decorative foliage:

Coleus. A very colorful plant. It has many shapes with different leaf edges and colors. To preserve their decorative appearance, plants should be pinched.

Araucaria. The plant can reach 1.6 m in height. Recommended to be grown as a single plant. Suitable for spacious rooms, young plants can be used to decorate the table.

Aspidistra. A very unpretentious plant, resistant to air pollution, light and watering restrictions. There are variegated forms.

Blooming

Clerodendron. A beautiful flowering plant. It can be grown as a vine, tied to a support, or as a shrub, pinching the tops.

Abutilone. There are varieties with green and variegated leaves with yellow and white spots and stripes. If the plant is pinched in the spring and cut back to half its height at the end of autumn, it will branch well and be more decorative.

Literature

1. Grodzinsky A. M. Phytodesign and phytoncides. - K.: Naukova Dumka, 1973.
2. Grodzinsky A. M. Experimental allelopathy. - K.: Naukova Dumka, 1987.
3. Tokin B.P. Healing plant poisons. - L.: Lenizdat, 1974.
4. Skipetrov V.P. Aeroions and life, Saransk, typ. “Red. Oct.”, 1997.
5. Sokolov S. Ya., Zamotaev I. P. Handbook of medicinal plants (herbal medicine). - M.: VITA; 1993.
6. Revelle P., Revelle Ch. Our habitat: In 4 books. Book 2. Water and air pollution: Per. from English - M.: Mir, 1995.
7. Lozanovskaya I. N., Orlov D. S., Sadovnikova L. K. Ecology and protection of the biosphere during chemical pollution: a textbook for chemistry. , chem. -technol. and biol. specialist. universities. - M.: Higher School - 1998.
8. General hygiene: propaedeutics of hygiene: Textbook. for foreigners students / E. I. Goncharuk, Yu. I. Kundiev, V. G. Bardov and others - 2nd ed. reworked and additional - K.: Vishcha school, 1999.
9. Impact of dangerous and harmful environmental factors on the human body. Meteorological aspects. In 2 volumes. Ed. Isaeva L.K. Volume 1.- M.: PAIMS, 1997.
10. Hessayon ​​D. G. All about indoor plants. - M.: Kladez, 1996.
11. Dudchenko L.G. Spicy-aromatic and spicy-flavoring plants: Directory. K.: Science. Dumka, 1989
12. Filin V. A. Videoecology. What is good for the eye and what is bad. M.: MC “Videoecology”, 1997.
13. Brud V. S., Konopatskaya I. Fragrant pharmacy. Secrets of aromatherapy. / lane from Polish. - M.: Publishing house. "GITIS", 1996.
14. Nebel B. Environmental Science: How the World Works: In 2 volumes. Transl. from English - M.: Mir, 1993
15. My beautiful garden. No. 1/2001. Special issue. Spicy and medicinal herbs.
16. Plants in the interior. June 2002. Balm for soul and body.
17. Flowers in the house No. 3/2002. Individual choice.
18. My beautiful garden. No. 12/2001. Beauty and health.
19. Green interior. No. 12/2001 Thematic issue of the magazine “Garden with your own hands”. Green cats, green mice.
20. Plants in the interior. September 2001. Lunar Rhapsody.
21. Plants in the interior. November 2001. The world of morning freshness.

Savina S. A., “Ecology of living space”

Plant respiration

represents a process corresponding to animal respiration. The plant absorbs atmospheric oxygen, and the latter affects the organic compounds of their body in such a way that water and carbon dioxide appear as a result. Water remains inside the plant, and carbon dioxide is released into the environment. In this case, destruction and waste of organic matter occurs; therefore, D. is directly opposite to the process of carbon assimilation. To a certain extent, it can be likened to the oxidation and combustion of a substance. Based on starch, the schematic equation of D. can be represented as follows:

C 6 H 10 O 5 (starch) + 6O 2 (oxygen) = 6CO 2 (carbon dioxide) + 5H 2 O (water)

This same equation, when read from right to left, gives a diagram of the assimilation process. The similarity of combustion with combustion is further enhanced by the fact that during combustion free energy is released, usually in the form of heat and sometimes light. The released energy goes to the body’s various needs: with the cessation of D., the life of the plant also stops [Some microorganisms (for example, anaerobic bacteria) can do without atmospheric oxygen; in such cases, the source of energy is not breathing, but other physiological processes.]. While the formation of water during D. is proven only on the basis of chemical tests, determining the loss of hydrogen by the plant (Boussingault), or by rather complex direct determinations (Lyaskovsky), it is quite simple to detect the release of carbon dioxide by the plant. For this purpose, pea or bean seeds that are just starting to germinate are placed in a graduated eudiometer at a certain height and then the eudiometer is closed with mercury. If after a few days we introduce a solution of caustic potassium into the eudiometer, we will notice that the mercury will rise significantly; Consequently, the eudiometer contains carbonic acid, which was absorbed by caustic potassium. For an accurate study (especially in quantitative terms) of plant biology, more complex devices are used. Their design is different, depending on whether they want to determine only the absorption of oxygen, or only the release of carbon dioxide, or, finally, both together. Volkov and Meyer's device meets the first goal. It consists of a glass tube bent in the shape of a U, with one elbow wider than the other. A plant and a small vessel with caustic potassium are inserted into the wide knee; then close it tightly with a ground glass stopper. A narrow elbow, previously calibrated and equipped with divisions, is closed with mercury. As carbonic acid forms, it is absorbed by potassium hydroxide; as a result, the volume of gas in the tube decreases and the mercury in the narrow elbow rises; The rise in mercury determines the amount of oxygen absorbed by the plant. To determine the amount of carbon dioxide released by a plant, it is best to use Pettenkofer tubes. The flow of air, previously freed from carbon dioxide, passes first through the device with the plants, and then through one or two Pettenkofer tubes filled with barite water [The air is drawn through using an aspirator]. All carbon dioxide released by plants is retained in the tubes in the form of carbon barium salt. Having determined by titration the amount of caustic barite remaining free, we find out the amount of carbon barium salt formed, and hence the amount of retained carbon dioxide. Instruments for simultaneous determination of the amounts of absorbed oxygen and released carbon dioxide (Bonnier and Mangin, Godlevsky, etc.), as too complex, can only be mentioned here.

D. in plants, of course, is not as vigorous as in warm-blooded animals, but it can be compared with D. in cold-blooded animals. The following figures from Garro give an idea of ​​its absolute value (intensity): 12 lilac buds, which, being dried at 110°, weigh 2 grams, exhaled 70 cubic meters within 24 hours. see carbon dioxide, and during the experiment their leaves managed to bloom. Next, the poppy sprouts, which then weighed 0.45 grams in a dry state, released 55 cubic meters in 24 hours. see carbon dioxide. D.'s energy depends on various conditions: internal and external. Thus, Saussure (1804) proved that the respiration of flowers is more energetic than the respiration of green leaves of the same plant - with equal weight and volume, and the leaves, in turn, respire (in the dark) more intensely than the stems and fruits. Here is an example: the flowers of a white lily consumed in 24 hours a volume of oxygen 5 times greater than their own volume - while the leaves were only 2.6 times greater. Determining the energy of D. in green leaves (and chlorophyll-bearing organs in general) in the light is associated with significant difficulties, since in light, especially bright light, D. is masked by a much more intense and directly opposite process of carbon assimilation (assimilation). Boussingault's experiments showed, for example, that a square decimeter of the leaf surface of cherry laurel (Prunus Laurocerasus) and oleander (Nerium Oleander) decomposes an average of 5.28 cubic meters in light in 1 hour. sant. carbon dioxide, and exhales in the same period on average only 0.33-0.34 cubic meters. sant. To prove the D. of leaves in the light, Garro performed this kind of experiment: he placed 100 grams in a vessel. leaves along with a cup of caustic potassium solution, and then closed the vessel from below with water. Because after some time. While the water level in the vessel rose, from this he concluded that the leaves were releasing carbon dioxide and, therefore, about their D. in the light. - Energy D. is also in close connection with the phenomena of growth. The faster a plant grows, the more it absorbs oxygen and releases carbon dioxide. D. of young plants germinating from seeds is carried out very energetically, and at the same time it is accompanied by a significant waste of organic matter. With more or less prolonged germination in the dark [In the dark, plants cannot assimilate and replenish the loss of carbon] D. can destroy more than half of all organic matter; through such destruction and burning, it releases the energy necessary for the construction of a young plant. Internal conditions, however, influence not only the intensity of D., but also its qualitative side, changing the CO 2 /O 2 ratio itself, i.e. e. the ratio of the volumes of carbon dioxide released and oxygen absorbed. Sometimes CO 2 /O 2 = 1, i.e., the same amount of carbon dioxide is released as oxygen is absorbed. But the CO 2 /O 2 ratio can be either less or more than one. So, for example, in growing organs (Palladin), and especially in germinating oily seeds, CO 2 /O 2 1. In the first case, therefore, oxygen is acquired and assimilated, in the second, it is lost.

In contrast to internal conditions, external ones influence only D.’s energy, without at all changing the CO 2 /O 2 ratio. The influence of temperature in this direction is the strongest, and at the same time it is the best known. D.'s energy up to a certain temperature limit (about 40° C.) increases almost in direct proportion to the increase in temperature, and then remains constant until the death of the plant. As for light, its direct influence is felt, according to the experiments of Bonnier and Mangin, by some slowing down of D.; indirectly, light can favor D., at least the D. of chlorophyll-bearing plants (Borodin), since in the light the amount of carbohydrates (the result of assimilation) increases, those very compounds through which the process of D. occurs. D. is not without influence. plants, as well as animals, and the partial pressure of oxygen in the surrounding atmosphere. - Although with D., only nitrogen-free organic compounds disappear and decrease - carbohydrates and fats [According to Winogradsky's research, sulfur bacteria and nitrifying microorganisms oxidize minerals, using the energy released in the process. The former oxidize hydrogen sulfide to sulfur and sulfuric acid, the latter oxidize ammonia into nitrous and nitric acid], but this does not yet prove that atmospheric oxygen during the act of D. directly acts on these substances, destroying and burning them; it is more likely that they serve only as indirect material for D. and that oxygen initially acts on a complex protein particle. In both animals and plants, the process of heat develops. But since plants easily lose this heat into the environment, their body temperature is no higher than the ambient air temperature, and often even lower. But in some periods of life - during seed germination and during flowering - the plant temperature can rise many degrees above the ambient temperature (see Plant warmth). In a few cases, the energy released during D. even appears in the form of glow or phosphorescence. Such luminescence has so far been reliably observed only in lower plants: in some fungi and bacteria (see Luminous plants). Finally, internal, or intramolecular, D. consists in the fact that plants, being in an oxygen-free environment and, therefore, not absorbing oxygen, still continue to release carbon dioxide. This phenomenon has little in common with ordinary normal fermentation and usually comes close to fermentation processes (see Intramolecular fermentation and alcoholic fermentation). Special literature about D. plants, see: Palladin, “Plant Physiology” (1891); A. S. Famintsyn, “Textbook of Plant Physiology” (1887); Sachs, J. "Vorlesungen über Pflanzen-Physiologie" (1887); Pfeffer, W. "Pflanzenphysiologie" (1881); Van-Tieghem, Ph. "Traité de Botanique" (1891).

G. Nadson.

Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron. - S.-Pb.: Brockhaus-Efron. 1890-1907 .

See what “Plant respiration” is in other dictionaries:

The release of carbon dioxide by a plant, not accompanied by the absorption of oxygen. Experiments have shown that plants (fruits, leaves, roots) in an oxygen-free atmosphere continue to release carbon dioxide for some time and at the same time inside, in the tissues,... ...

One of the main vital functions, a set of processes that ensure the entry of O2 into the body, its use in redox processes, as well as the removal from the body of CO2 and certain other compounds that are the final... ... Biological encyclopedic dictionary

BREATHING, breathing, cf. (book). Action under Ch. breathe. Intermittent breathing. Artificial respiration (techniques used to resume lung activity during its temporary cessation; honey). || The process of oxygen absorption by a living organism... ... Ushakov's Explanatory Dictionary

Diaphragmatic (abdominal) type of breathing in humans This term has other meanings, see Cellular respiration ... Wikipedia

A set of processes that ensure the entry of oxygen into the body and the release of carbon dioxide from it (external D.) and the use of oxygen by cells and tissues for the oxidation of organic substances with the release of... Great Soviet Encyclopedia

In a commonly used sense, it means a series of movements of the chest continuously alternating during life in the form of inhalation and exhalation and determining, on the one hand, an influx of fresh air into the lungs, and on the other, the removal of already spoiled air from them... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

Breathing is the most advanced form of the oxidative process and the most efficient way to obtain energy. The main advantage of respiration is that the energy of the oxidized substance of the substrate on which the microorganism grows... ... Biological encyclopedia

A set of processes that ensure the entry of oxygen into the body and the removal of carbon dioxide (external respiration), as well as the use of oxygen by cells and tissues for the oxidation of organic substances, releasing the energy necessary for... ... Big Encyclopedic Dictionary

BREATHING, the process by which air enters and leaves the lungs for the purpose of GAS EXCHANGE. When you inhale, the muscles of the diaphragm raise the ribs, thereby increasing the volume of the CHEST, and air enters the LUNGS. When you exhale, the ribs lower and... Scientific and technical encyclopedic dictionary

BREATHING, BREATHING, I; Wed 1. The intake and release of air by the lungs or (in some animals) other relevant organs as a process of absorption of oxygen and release of carbon dioxide by living organisms. Respiratory system. Noisy, heavy... encyclopedic Dictionary

It has been established that the biochemical reactions occurring in the human and animal bodies are the same. Do plants breathe? In many experiments, scientists gave a positive answer to this question.

Oxygen is necessary for the oxidation of organic substances. In this case, the energy contained in the molecules is released. But if a person has a mouth, lungs, and a nose, through which oxygen enters the body, how do plants breathe? More on this later in the article.

General information

In ancient times it was deprived of oxygen. However, there were quite a lot. In the process of evolution, plants have developed the ability to absorb it. As a result, the energy of sunlight was converted into oxygen and released into the atmosphere, which gave life to other organisms. One of the first experiments in which it was found out how plants respire was an experiment with beets and cabbage. At first, crops were grown outdoors. Then half of them were placed in a chamber where the oxygen content was about 2.5%. The other part remained in the air, in which O 2 was

21%. Lighting for both was provided around the clock. It was assumed that plants placed in the chamber would die without oxygen. However, after six days, their weight was significantly higher than that of those who remained in the air. How do plants breathe without oxygen? More on this later.

How do plants breathe in light and in darkness?

The fact is that representatives of the flora are able to use solar energy very efficiently. When darkness falls, there is a kind of “switching” from one source to another. How do plants breathe in light and in darkness? When solar energy enters, organic substances are synthesized. When darkness sets in, the process of oxidation of compounds occurs. In the latter case they speak of “dark” breathing, and in the first - of “light” breathing. The ability to make such switching allows saving internal energy reserves. But representatives of the flora also breathe in the light, but this process does not benefit them. Absorbing carbon dioxide. It is their main food. As a result, growth is slowing down somewhat. However, there are also representatives of the flora for which light does not interfere with their development. For example, corn does not have light breathing.

Reasons for the development of light breathing

The beginning, as scientists suggest, was the symbiosis of photosynthetic primitive organisms with non-photosynthetic ones. Symbiosis is understood as mutual participation in processes, which is beneficial to both parties. Small photosynthetics living in water absorbed carbon dioxide from the environment, releasing oxygen. If there were no breathing, absorbing O 2 organisms in the environment, then unbearable conditions would have been created for photosynthetics. But in the process of evolution, those representatives of the organic world also survived that were somehow useful for non-photosynthetics.

One of the compounds that is formed during photosynthesis is glycolic acid. This substance is also released by some modern algae. As a result, non-photosynthetics received glycolic acid from photosynthetics. This, in turn, contributed to increased oxygen consumption for oxidation of the compound.

Conclusion

Glycolic acid is the same substance that, in the process of several biochemical reactions, is oxidized and forms carbon dioxide.

Accordingly, we can conclude that the more oxygen in the air, the more glycolic acid is formed. This provides greater intensity of light breathing. As a result, more carbon dioxide is released into the environment. Scientists suggest that, according to a similar principle, plants developed the ability to regulate light respiration in accordance with the level of carbon dioxide in the air. Organisms not only absorbed oxygen from the environment, which was harmful to photosynthetics, but also released carbon dioxide, which they needed.

Experiments

You can see in practice how plants breathe. The 6th grade biology curriculum covers this issue in great detail. To observe the process, you can take a leaf from an indoor flower. In addition, you will need a magnifying glass, a transparent container filled with water, and a cocktail straw. Experience proving that plants respire allows us not only to understand the process, but also the sample in oxygen. Small holes can be seen on the cut of the sheet. Part of the sample is immersed in water, and bubbles are released. There is another way to see how plants breathe. To do this, take a bottle, pour water into it, leaving about two to three centimeters empty. A leaf on a long stem is inserted so that its tip is immersed in the liquid. The opening of the bottle is tightly covered with plasticine (instead of cork). A hole is made in it for a straw, which is inserted so that it does not touch the water. Use a straw to suck out the air from the bottle. Bubbles will begin to appear from the stem immersed in water.

On our planet, living and inanimate nature are closely connected. Plants and the sun play a special role in all vital processes on Earth. Let's take a closer look at the topic “The Sun, Plants and You and Me” about the world around us.

Features of plant nutrition

All plants inhabiting the globe are living beings that can breathe and eat.

It's no secret that plants absorb water from the soil in which various salts are dissolved. But how do plants obtain the most valuable nutrients - starch and sugar? These components are not present in the soil, but they are present in the plants themselves. This riddle haunted the most prominent scientists for a long time, until finally an answer was found.

As it turned out during research, plant leaves are real little wizards that can “cook” food from carbon dioxide and water. They receive water thanks to the roots, and they, in turn, absorb it from the ground. The foliage absorbs carbon dioxide from the air. But for this magical “kitchen” to work, you need sunlight.

Rice. 1. Photosynthesis occurs in leaves.

The process of creating nutrients from carbon dioxide and water under the influence of sunlight is called photosynthesis. All parts of the plant take part in this process:

TOP 4 articleswho are reading along with this

• the root draws in salt solutions from the soil;
• the stem conducts these solutions upward;
• in the leaves they are converted into sugar and starch.

Why do we need light to get nutrients? The thing is that the sun's rays carry with them a powerful flow of energy, which triggers many processes. Without energy, no creature could live, and no mechanism could work.

Rice. 2. Sunlight is a source of energy.

This discovery turned out to be very important, because it became clear that the existence of animals and people on the planet is impossible without plants. Nature has decreed that only one creature on Earth - plants - are capable of producing nutritional components from carbon dioxide and water. Animals and people, by eating plants, provide themselves with vital energy.

Plant respiration

During a thorough study of plants, scientists came to another interesting conclusion. It turns out that during the “cooking” of nutrients by plants, oxygen is also produced - a valuable gas that all living beings need for breathing.

If there are no plants, there will be such a small amount of oxygen left in the air that it will not be enough to support life on Earth. Interestingly, all plants, when feeding, release much more oxygen than they absorb.

Plants are the lungs of our planet. Every year they release approximately 45 million tons of pure oxygen! The more trees, shrubs and grasses there are on the globe, the cleaner and healthier the air. This is why it is so important to take good care of our green friends.

Rice. 3. Forests are the “lungs” of our planet.

Let's look at the similarities and differences between the processes of respiration and plant nutrition:

• breathing charges plants with valuable energy, and thanks to photosynthesis, all living creatures on the planet receive food and oxygen;
• respiration occurs constantly, regardless of external factors, and photosynthesis can only occur under the influence of sunlight;
• Absolutely all plant cells participate in the respiration process, and only green cells participate in photosynthesis;
• During respiration, plants absorb oxygen from the air, and during photosynthesis, they release it;
• During respiration, substances are broken down in plants, and during photosynthesis, on the contrary, they are formed.

What is the connection between plants, people and the sun

Without the heat and light that the sun provides our planet, plants cannot exist, because the processes of nutrition and respiration cannot be carried out without solar energy.

If there are no plants on Earth or very few of them, humans will face two serious problems:

• the food source will be significantly reduced;
• the most important producer of oxygen will disappear.

Without plants, a person simply cannot breathe, and without breathing, life itself is impossible.

What have we learned?

When studying the topic “The Sun, Plants and You and Me” (grade 3), we learned how the two most important processes occur in plants: nutrition and respiration. We found out what effect sunlight has on these processes and what products are produced. Without the oxygen that plants produce, life on the planet would be impossible.

Test on the topic

Evaluation of the report

Average rating: 4.2. Total ratings received: 174.