Almost all living beings are capable of moving at least part of their body. Thus, the growing parts of plants constantly change their position in space and make movements. For example, young seedlings and shoot tips with leaves bend in the direction of the light source. By bending, plant organs occupy an optimal position in relation to the light source. When a seed germinates, regardless of its position, the embryonic root necessarily grows downward, and the main shoot grows upward. If a seedling is turned upside down and the shoot down, then after a while the root will bend down and the shoot will bend up.

Unlike plants, most animals can move their entire body and move from place to place. The simplest is the passive movement of animals in air currents and water currents.

One of the most ancient and simplest is amoeboid movement with the help of protrusions. In this way, the single-celled animal amoeba vulgaris moves, as well as phagocytes - specialized protective cells that destroy pathogens in the body of animals and humans.

Many unicellular and small multicellular animals move with the help of flagella and cilia. There are usually one or two flagella. They are longer than eyelashes. With the help of flagella, unicellular organisms, such as bodo, as well as green euglena and chlamydomonas, move. Cilia serve as organelles for the movement of ciliates, the larvae of many aquatic worms and a number of other animals.

Muscles are involved in the movement of larger animals. They can contract and, conversely, lengthen, setting the animal’s body in motion. Watching an earthworm crawl, you can see a wave of contractions running through its body. In this case, thickened areas of the body alternate with thin and elongated ones.

Cephalopods: squid, octopus and cuttlefish - can move different ways. Some glide along the waves (Argonaut octopus), others rush like a rocket (squid, octopus) (Fig. 78).

Rice. 78. Octopus jet propulsion

Arthropods: crayfish, spiders, insects have developed special locomotion organs - limbs. They consist of segments and are driven by muscles. In addition to legs, many insects have wings. With their help, they mastered the air environment. The first flying insects appeared on Earth about 200 million years ago.

A special musculoskeletal system, consisting of bones and muscles, exists in vertebrates - fish, amphibians, reptiles, birds and mammals (animals). Thanks to this, vertebrates are able to actively move in the air, water, soil and on its surface.

Fish swim in water in different ways and at different speeds. The fins, especially the caudal one, play an important role in this process. With its help, the fish swim forward.

Active swimmers such as whales and dolphins have developed forelimbs into flippers. The main organ of movement of these aquatic animals is a powerful tail ending in a two-lobed fin.

Beavers, muskrats, frogs, and toads can actively move both on solid ground and in water. Their hind legs are equipped with swimming membranes stretched between the toes.

The structure of many animals is primarily adapted for movement. Mobility allows them to find food, leave unfavorable places, and escape from predators. Thus, movement is one of the most important properties of living organisms.

Answer the questions

1. What movements do plants make?
2. What is the importance of movement in plant life?
3. What organs do animals use to move?

New concepts

Movements in plants. Movement of animals.

Think!

Why have animals, unlike plants, developed different modes of locomotion?

My laboratory

The limbs of insects are very diverse in structure and function: swimming (diving beetle), for collecting pollen (bumblebee), grasping (louse), running (ant), digging (mole cricket) (Fig. 79). What do you think is responsible for these modifications of the limbs?

Rice. 79. Motor limbs of insects

The mechanism of jet propulsion of cephalopods is interesting. Having filled its muscular sac-like body with water, the animal sharply contracts its muscles. At the same time, water is forcefully thrown out of the body through the funnel and the mollusk, like a rocket, rushes forward. Suctions of water and jet thrusts into the body cavity follow one after another with elusive speed, and the mollusk rushes like a rocket in the blue of the ocean. The muscles of cephalopods are well developed. With its help, the funnel can turn in any direction, which allows the animal to quickly turn around. Squids, constantly working as a sac body, can rush in pursuit of fish at speeds of up to 50 km/h, even jump out of the water and fly some distance through the air.

When moving on land, vertebrates walk, jump and run. At the same time, they use four (less often two) limbs as levers. The long-legged cheetah runs the fastest over short distances. It reaches a speed of 110 km/h in a few seconds, but can only hold it for 15 seconds. Antelopes are capable of accelerating up to 110 km/h and maintaining this speed for several minutes, and then running at a speed of 60 km/h for more than half an hour.

Unlike most animals that move freely in space, plants lead an attached lifestyle and seem motionless to us. In fact, the cytoplasm and organelles of plant cells, various plant organs: stems, roots, leaves, flowers are in constant motion. So, in the soil, roots move towards nutrients. This helps expand the area where roots live and better use water and minerals contained in it. Aboveground shoots of plants move upward and wider in the air, increasing the area of ​​air supply.

The stems of the vines move in the direction of the support - large tree trunks, wrap around them and carry the leaves towards the light.

You can observe the movement of flowers and inflorescences in a number of plants. For example, dandelion blossoms open in the morning and close in the evening. Tulip flowers open when the air temperature rises or in bright light, and close when shaded or the temperature drops. The movements of flowers are associated with their adaptations to cross-pollination by insects and protection from unfavorable conditions.

The basis of any movement of a plant is its growth. It depends on environmental conditions (temperature, light, gravity, etc.) and on the content of hormones in cells. Most often, movement manifests itself in the form of bending of organs. For example, the tops of the shoots bend towards the light.

The stem and root react differently to gravity. The stem grows upward, in the opposite direction from the action of gravity, and the root grows downward, in the direction of this force.

Covering epithelium. In most multicellular animals, they are carried out with the help of special organs, the structure of which is unique in different animals and depends on the type of their locomotion and environmental conditions (land, water, air). But even in these cases, the movement of the organism and its parts is the result of a few types of cellular motility.

Some animals (for example, hydroid polyps) and many plants are characterized by growth movements.

Forms of cell motility

• Pseudopodia (pseudopods) provide amoeboid movement (slow flow of cytoplasm associated with a change in cell shape)
• Cilia and flagella provide ciliary and flagellar movement
• Myocytes (muscle tissue cells) provide muscle contraction

In addition to these main forms, there are others, less well studied (sliding movement of gregarines, myxobacteria and filamentous cyanobacteria, contraction of spasmonema suvoek, etc.).

Locomotor apparatus and locomotion organs of multicellular animals

• Special body appendages with the help of which animals cling to uneven surfaces of the substrate (bristles, scales, scutes) or attach to it (suction cups).
• Limbs representing a system of levers driven by muscle contractions (the most common design).

Organs can be used by organisms that have freedom of movement. In the absence of one (in attached aquatic animals - sponges, corals, etc., leading a sedentary lifestyle), they use cilia and flagella to set in motion their environment, delivering them food and oxygen.

Purposeful movements are possible only with the coordinated work of a significant number of muscles or cilia, the coordination of which, as a rule, is carried out by the nervous system.

Classification

Along the paths of movement (movement)

• On the substrate, that is, on solid or liquid support (walking, running, jumping, crawling, sliding)
• Free in the water - swimming
• Free in the air - flying, gliding, soaring
• In the substrate (drilling)

By activity

Passive

In water and air, movement can also be passive:

• When moving over long distances, some spiders release webs and are carried away by air currents.
• soaring observed in birds using air currents
• Some aquatic animals have devices that ensure that their bodies are maintained in a suspended state (vacuoles in the outer layer of radiolarian protoplasm, air bubbles in siphonophore colonies, etc.).

Active

• In water the following is carried out:
  • using specialized rowing devices (from hairs and flagella to modified limbs of aquatic turtles, birds, pinnipeds)
  • bending of the whole body (most fish, tailed amphibians, etc.)
  • reactive method - pushing water out of body cavities (jellyfish, cephalopods, etc.).
• In the air, flying is characteristic of most insects, birds and some mammals (bats). Movement by air so-called. flying fish, frogs, mammals (flying squirrels, etc.) - not flying, but an elongated gliding jump, carried out with the help of such supporting devices as elongated pectoral fins, interdigital membranes of the feet, folds of skin, etc.

Evolution

During evolution, the types of animal movements became more complex. The emergence of a rigid skeleton and striated muscles was one of the important stages of evolution. As a result, the structure of the nervous system became more complex, a variety of movements appeared, and the vital capabilities of organisms expanded.

Human movements

Are the most important way it interacts with environment and active influence on it.

They are very diverse:

• Movements associated with autonomic functions
• locomotion
• labor
• household
• sports
• related to speech and writing.

“...all external manifestations of brain activity can really be reduced to muscle movement” I. M. Sechenov

Studying

Two directions can be distinguished in the study of animal and human movement:

• identification of biomechanical characteristics of the musculoskeletal system, kinematic and dynamic description of natural movements
• neurophysiological - elucidation of the patterns of movement control by the nervous system

The muscles that carry out movement are reflexively controlled by impulses from the central nervous system.

Basic locomotor movements, being inherited (certainly reflex), develop during individual development and as a result of constant exercise. Mastering new movements is a complex process of forming new conditioned reflex connections and strengthening them. With repeated repetitions, voluntary movements are performed more consistently, more economically, and gradually become automated. The most important role in the regulation of movement belongs to the signals entering the nervous system from proprioceptors located in the muscles, tendons and joints, reporting the direction, magnitude and speed of the movement being performed, activating reflex arcs in different parts of the nervous system, the interaction of which ensures coordination of movement.

Movements in plants

Passive (hygroscopic)

Associated with changes in the water content in the colloids that make up the cell membrane.

They play an important role for flowering plants in the distribution of seeds and fruits.

• The rose of Jericho, growing in the desert of Arabia, has branches that are curled up in dry air, but in damp air they unfold, tear off the substrate and are carried by the wind.
• Due to their hygroscopicity, the fruits of feather grass and crane grass are buried in the ground
• In yellow acacia, a mature bean dries out, its two flaps spiral, and the seeds are scattered with force.

Active

Active movements are based on the phenomena of irritability and contractility of plant cytoplasmic proteins, as well as growth processes. Perceiving the influences of the environment, plants react to them by increasing the intensity of metabolism, accelerating the movement of the cytoplasm, growth and other movements. The irritation perceived by the plant is transmitted along cytoplasmic strands - plasmodesmata, and then the plant as a whole responds to the irritation. Weak irritation causes an increase, strong irritation causes inhibition of physiological processes in the plant.

Slow (growth)

These include:

• tropisms (irritation acts in one direction and one-sided growth occurs, resulting in bending of the organ - geotropism, phototropism, chemotropism, etc.)
• nastia (plant response to the action of stimuli that do not have a specific direction - thermonastia, photonastia, etc.)

Fast (contractile)

They are caused by the unilateral action of stimuli (toward or away from the stimulus): light (phototaxis), chemicals (chemotaxis), etc.

Carried out:

• (in most cases) with the help of flagella (flagellate algae, bacteria, zoospores of nonmotile algae, as well as lower fungi, spermatozoa of algae, fungi, mosses, ferns and some gymnosperms)
• (less commonly) as a result of unilateral secretion of mucus (green algae Closterium), active snake-like bends (blue-green algae Oscillatoria, sulfur bacterium Beggiatoa), unilateral movement of protoplasm (motile diatoms) or the formation of protoplasmic outgrowths (myxomycetes)

Evolution

The evolution of plants went in the direction of their loss of the ability to locomotor movement. In the vegetative state, only bacteria, some algae and myxomycetes are mobile: in other algae and lower fungi, locomotor movements are inherent only in zoospores and sperm, in higher plants (mosses, mosses, horsetails, ferns, cycads and ginkgo) - only in sperm.

see also

Notes

Literature

• Timiryazev K. A., Izbr. soch., vol. 4, M., 1949, lecture 9
• Kursanov L.I., Komarnitsky N.A., Course of lower plants, 3rd ed., M., 1945.
• Darwin Ch., The ability to move in plants, Works, vol. 8, M. - L., 1941
• Zenkevich L. A., Essays on the evolution of the locomotor system of animals, “Journal general biology", 1944, v. 5, No. 3: Engelhardt V. A., Chemical bases of the motor function of cells and tissues, "Bulletin of the USSR Academy of Sciences", 1957, No. 11, p. 58
• Kalmykov K. f.. Studies of the phenomena of plant irritability in Russian science of the second half of the 19th century, “Tr. Institute of History of Natural Science and Technology of the USSR Academy of Sciences", 1960, v. 32, v, 7
• Magnus R., Body Installation, trans. from German, M. - L., 1962
• Lyubimova M.N., On the characteristics of the motor system of Mimosa pudica plants, in the book: Molecular Biology. Problems and prospects, M., 1964
• Poglazov B.F., Structure and functions of contractile proteins, M., 1965
• Bernstein N. A., Essays on the physiology of movements and physiology of activity, M., 1966
• Sukhanov V.B., Materials on the location of vertebrates, “Bulletin of the Moscow Society of Natural Scientists”, 1967, v. 72, v. 2
• Alexander R., Biomechanics, trans. from English, M., 1970.

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Many movements are carried out due to the work of the cilia of the integumentary epithelium. In most multicellular animals, they are carried out with the help of special organs, the structure of which is unique in different animals and depends on the type of their locomotion and environmental conditions (land, water, air). But even in these cases, the movement of the organism and its parts is the result of a few types of cellular motility.

Some animals (for example, hydroid polyps) and many plants are characterized by growth movements.

Forms of cell motility

• Pseudopodia (pseudopods) provide amoeboid movement (slow flow of cytoplasm associated with a change in cell shape)
• Cilia and flagella provide ciliary and flagellar movement
• Myocytes (muscle tissue cells) provide muscle contraction

In addition to these main forms, there are others, less well studied (sliding movement of gregarines, myxobacteria and filamentous cyanobacteria, contraction of spasmonema suvoek, etc.).

Locomotor apparatus and locomotion organs of multicellular animals

• Special body appendages with the help of which animals cling to uneven surfaces of the substrate (bristles, scales, scutes) or attach to it (suction cups).
• Limbs representing a system of levers driven by muscle contractions (the most common design).

Organs can be used by organisms that have freedom of movement. In the absence of one (in attached aquatic animals - sponges, corals, etc., leading a sedentary lifestyle), they use cilia and flagella to set in motion their environment, delivering them food and oxygen.

Purposeful movements are possible only with the coordinated work of a significant number of muscles or cilia, the coordination of which, as a rule, is carried out by the nervous system.

Classification

Along the paths of movement (movement)

• On the substrate, that is, on solid or liquid support (walking, running, jumping, crawling, sliding)
• Free in the water - swimming
• Free in the air - flying, gliding, soaring
• In the substrate (drilling)

By activity

Passive

In water and air, movement can also be passive:

• When moving over long distances, some spiders release webs and are carried away by air currents.
• soaring observed in birds using air currents
• Some aquatic animals have devices that ensure that their bodies are maintained in a suspended state (vacuoles in the outer layer of radiolarian protoplasm, air bubbles in siphonophore colonies, etc.).

Active

• In water the following is carried out:
  • using specialized rowing devices (from hairs and flagella to modified limbs of aquatic turtles, birds, pinnipeds)
  • bending of the whole body (most fish, tailed amphibians, etc.)
  • reactive method - pushing water out of body cavities (jellyfish, cephalopods, etc.).
• In the air, flying is characteristic of most insects, birds and some mammals (bats). Movement by air so-called. flying fish, frogs, mammals (flying squirrels, etc.) - not flying, but an elongated gliding jump, carried out with the help of such supporting devices as elongated pectoral fins, interdigital membranes of the feet, folds of skin, etc.

Evolution

During evolution, the types of animal movements became more complex. The emergence of a rigid skeleton and striated muscles was one of the important stages of evolution. As a result, the structure of the nervous system became more complex, a variety of movements appeared, and the vital capabilities of organisms expanded.

Human movements

They are the most important way of its interaction with the environment and active influence on it.

They are very diverse:

• Movements associated with autonomic functions
• locomotion
• labor
• household
• sports
• related to speech and writing.

“...all external manifestations of brain activity can really be reduced to muscle movement” I. M. Sechenov

.

Studying

Two directions can be distinguished in the study of animal and human movement:

• identification of biomechanical characteristics of the musculoskeletal system, kinematic and dynamic description of natural movements
• neurophysiological - elucidation of the patterns of movement control by the nervous system

The muscles that carry out movement are reflexively controlled by impulses from the central nervous system.

Basic locomotor movements, being inherited (certainly reflex), develop during individual development and as a result of constant exercise. Mastering new movements is a complex process of forming new conditioned reflex connections and strengthening them. With repeated repetitions, voluntary movements are performed more consistently, more economically, and gradually become automated. The most important role in the regulation of movement belongs to the signals entering the nervous system from proprioceptors located in the muscles, tendons and joints, reporting the direction, magnitude and speed of the movement being performed, activating reflex arcs in different parts of the nervous system, the interaction of which ensures coordination of movement.

Movements in plants

Passive (hygroscopic)

Associated with changes in the water content in the colloids that make up the cell membrane.

They play an important role for flowering plants in the distribution of seeds and fruits.

• The rose of Jericho, growing in the desert of Arabia, has branches that are curled up in dry air, but in damp air they unfold, tear off the substrate and are carried by the wind.
• Due to their hygroscopicity, the fruits of feather grass and crane grass are buried in the ground
• In yellow acacia, a mature bean dries out, its two flaps spiral, and the seeds are scattered with force.

Active

Active movements are based on the phenomena of irritability and contractility of plant cytoplasmic proteins, as well as growth processes. Perceiving the influences of the environment, plants react to them by increasing the intensity of metabolism, accelerating the movement of the cytoplasm, growth and other movements. The irritation perceived by the plant is transmitted along cytoplasmic strands - plasmodesmata, and then the plant as a whole responds to the irritation. Weak irritation causes an increase, strong irritation causes inhibition of physiological processes in the plant.

Slow (growth)

These include:

• tropisms (irritation acts in one direction and one-sided growth occurs, resulting in bending of the organ - geotropism, phototropism, chemotropism, etc.)
• nastia (plant response to the action of stimuli that do not have a specific direction - thermonastia, photonastia, etc.)

Fast (contractile)

They are caused by the unilateral action of stimuli (toward or away from the stimulus): light (phototaxis), chemicals (chemotaxis), etc.

Carried out:

• (in most cases) with the help of flagella (flagellate algae, bacteria, zoospores of nonmotile algae, as well as lower fungi, spermatozoa of algae, fungi, mosses, ferns and some gymnosperms)
• (less commonly) as a result of unilateral secretion of mucus (green algae Closterium), active snake-like bends (blue-green algae Oscillatoria, sulfur bacterium Beggiatoa), unilateral movement of protoplasm (motile diatoms) or the formation of protoplasmic outgrowths (myxomycetes)

Evolution

The evolution of plants went in the direction of their loss of the ability to locomotor movement. In the vegetative state, only bacteria, some algae and myxomycetes are mobile: in other algae and lower fungi, locomotor movements are inherent only in zoospores and sperm, in higher plants (mosses, mosses, horsetails, ferns, cycads and ginkgo) - only in sperm.

see also

Write a review on the article "Movement (biology)"

Notes

Literature

• Timiryazev K. A., Izbr. soch., vol. 4, M., 1949, lecture 9
• Kursanov L.I., Komarnitsky N.A., Course of lower plants, 3rd ed., M., 1945.
• Darwin Ch., The ability to move in plants, Works, vol. 8, M. - L., 1941
• Zenkevich L. A., Essays on the evolution of the locomotor system of animals, "Journal of General Biology", 1944, vol. 5, No. 3: Engelhardt V. A., Chemical bases of the motor function of cells and tissues, "Bulletin of the USSR Academy of Sciences", 1957, No. 11, p. 58
• Kalmykov K. f.. Studies of the phenomena of plant irritability in Russian science of the second half of the 19th century, “Tr. Institute of History of Natural Science and Technology of the USSR Academy of Sciences", 1960, v. 32, v, 7
• Magnus R., Body Installation, trans. from German, M. - L., 1962
• Lyubimova M.N., On the characteristics of the motor system of Mimosa pudica plants, in the book: Molecular Biology. Problems and prospects, M., 1964
• Poglazov B.F., Structure and functions of contractile proteins, M., 1965
• Bernstein N. A., Essays on the physiology of movements and physiology of activity, M., 1966
• Sukhanov V.B., Materials on the location of vertebrates, “Bulletin of the Moscow Society of Natural Scientists”, 1967, v. 72, v. 2
• Alexander R., Biomechanics, trans. from English, M., 1970.

Excerpt characterizing Movement (biology)

– From General Field Marshal Kutuzov? - he asked. - Good news, I hope? Was there a collision with Mortier? Victory? It's time!
He took the dispatch, which was addressed to him, and began to read it with a sad expression.
- Oh my god! My God! Shmit! - he said in German. - What a misfortune, what a misfortune!
Having run through the dispatch, he put it on the table and looked at Prince Andrei, apparently thinking about something.
- Oh, what a misfortune! The matter, you say, is decisive? Mortier was not taken, however. (He thought.) I am very glad that you brought good news, although the death of Shmit is an expensive price to pay for victory. His Majesty will probably wish to see you, but not today. Thank you, take a rest. Tomorrow be on the way out after the parade. However, I'll let you know.
The stupid smile that had disappeared during the conversation reappeared on the face of the Minister of War.
- Goodbye, thank you very much. The Emperor will probably wish to see you,” he repeated and bowed his head.
When Prince Andrei left the palace, he felt that all the interest and happiness brought to him by the victory had now been abandoned by him and transferred to the indifferent hands of the Minister of War and the courteous adjutant. His whole mindset instantly changed: the battle seemed to him like an old, distant memory.

Prince Andrei stayed in Brünn with his friend, the Russian diplomat Bilibin.
“Ah, dear prince, there is no nicer guest,” said Bilibin, going out to meet Prince Andrei. - Franz, the prince’s things are in my bedroom! - he turned to the servant who was seeing Bolkonsky off. - What, a harbinger of victory? Wonderful. And I’m sitting sick, as you can see.
Prince Andrei, having washed and dressed, went out to the diplomat’s luxurious office and sat down to the prepared dinner. Bilibin calmly sat down by the fireplace.
Prince Andrei, not only after his journey, but also after the entire campaign, during which he was deprived of all the comforts of cleanliness and grace of life, experienced a pleasant feeling of relaxation among those luxurious living conditions to which he had become accustomed since childhood. In addition, after the Austrian reception, he was pleased to talk, at least not in Russian (they spoke French), but with a Russian person who, he assumed, shared the general Russian disgust (now especially vividly felt) for the Austrians.
Bilibin was a man of about thirty-five, single, in the same company as Prince Andrei. They knew each other back in St. Petersburg, but they became even closer on Prince Andrei’s last visit to Vienna together with Kutuzov. Just as Prince Andrei was a young man who promised to go far in the military field, so, and even more, did Bilibin promise in the diplomatic field. He was still a young man, but no longer a young diplomat, since he began serving at the age of sixteen, was in Paris, in Copenhagen, and now occupied a rather significant position in Vienna. Both the Chancellor and our envoy in Vienna knew him and valued him. He was not one of that large number of diplomats who are required to have only negative merits, not do well-known things and speak French in order to be very good diplomats; he was one of those diplomats who love and know how to work, and, despite his laziness, he sometimes spent the night at his desk. He worked equally well, no matter what the nature of the work was. He was not interested in the question “why?”, but in the question “how?”. What the diplomatic matter was, he didn’t care; but to draw up a circular, memorandum or report skillfully, accurately and gracefully - he found great pleasure in this. Bilibin's merits were valued, in addition to his written works, also by his art of addressing and speaking in higher spheres.
Bilibin loved conversation just as he loved work, only when the conversation could be elegantly witty. In society, he constantly waited for an opportunity to say something remarkable and entered into conversation only under these conditions. Bilibin's conversation was constantly peppered with original witty, complete phrases of general interest.
These phrases were produced in Bilibin’s internal laboratory, as if on purpose, of a portable nature, so that insignificant secular people could conveniently remember them and transfer them from living rooms to living rooms. And indeed, les mots de Bilibine se colportaient dans les salons de Vienne, [Bilibin’s reviews were distributed throughout Viennese living rooms] and often had an influence on so-called important matters.
His thin, emaciated, yellowish face was all covered with large wrinkles, which always seemed as cleanly and diligently washed, like fingertips after a bath. The movements of these wrinkles constituted the main play of his physiognomy. Now his forehead wrinkled in wide folds, his eyebrows rose upward, now his eyebrows went down, and large wrinkles formed on his cheeks. The deep-set, small eyes always looked straight and cheerful.
“Well, now tell us your exploits,” he said.
Bolkonsky, in the most modest way, without ever mentioning himself, told the story and the reception of the Minister of War.
“Ils m"ont recu avec ma nouvelle, comme un chien dans un jeu de quilles, [They accepted me with this news, as they accept a dog when it interferes with a game of skittles,] he concluded.
Bilibin grinned and loosened the folds of his skin.
“Cependant, mon cher,” he said, examining his nail from afar and picking up the skin above his left eye, “malgre la haute estime que je professe pour le Orthodox Russian army, j"avoue que votre victoire n"est pas des plus victorieuses. [However, my dear, with all due respect to the Orthodox Russian army, I believe that your victory is not the most brilliant.]
He continued the same way French, pronouncing in Russian only those words that he contemptuously wanted to emphasize.
- How? You with all your weight fell upon the unfortunate Mortier with one division, and this Mortier leaves between your hands? Where is the victory?
“However, seriously speaking,” answered Prince Andrei, “we can still say without boasting that this is a little better than Ulm...
- Why didn’t you take us one, at least one marshal?
– Because not everything is done as expected, and not as regularly as at the parade. We expected, as I told you, to reach the rear by seven o'clock in the morning, but did not arrive at five in the evening.
- Why didn’t you come at seven o’clock in the morning? “You should have come at seven o’clock in the morning,” Bilibin said smiling, “you should have come at seven o’clock in the morning.”
– Why didn’t you convince Bonaparte through diplomatic means that it was better for him to leave Genoa? – Prince Andrei said in the same tone.
“I know,” Bilibin interrupted, “you think it’s very easy to take marshals while sitting on the sofa in front of the fireplace.” This is true, but still, why didn’t you take it? And do not be surprised that not only the Minister of War, but also the August Emperor and King Franz will not be very happy with your victory; and I, the unfortunate secretary of the Russian embassy, ​​do not feel any need to give my Franz a thaler as a sign of joy and let him go with his Liebchen [sweetheart] to the Prater... True, there is no Prater here.
He looked straight at Prince Andrei and suddenly pulled the collected skin off his forehead.
“Now it’s my turn to ask you why, my dear,” said Bolkonsky. “I confess to you that I don’t understand, maybe there are diplomatic subtleties here that are beyond my weak mind, but I don’t understand: Mack is losing an entire army, Archduke Ferdinand and Archduke Charles do not show any signs of life and make mistakes after mistakes, finally, alone Kutuzov wins a real victory, destroys the charme [charm] of the French, and the Minister of War is not even interested in knowing the details.
“That’s exactly why, my dear.” Voyez vous, mon cher: [You see, my dear:] hurray! for the Tsar, for Rus', for the faith! Tout ca est bel et bon, [all this is fine and good,] but what do we, I say, the Austrian court, care about your victories? Bring us your good news about the victory of Archduke Charles or Ferdinand - un archiduc vaut l "autre, [one Archduke is worth another,] as you know - even over a company of Bonaparte’s fire brigade, that’s another matter, we’ll thunder into the cannons. Otherwise this , as if on purpose, can only tease us. Archduke Charles does nothing, Archduke Ferdinand is covered in shame. You abandon Vienna, you no longer defend, comme si vous nous disiez: [as if you told us:] God is with us, and God is with you, with your capital. One general, whom we all loved, Shmit: you bring him under the bullet and congratulate us on the victory!... Agree that it is impossible to think of anything more irritating than the news you bring. C "est comme un fait expres, Comme un fait expres. [It’s as if on purpose, as if on purpose.] Besides, well, if you had definitely won a brilliant victory, even if Archduke Charles had won, what would it have changed in the general course of affairs? It is too late now that Vienna is occupied by French troops.
-How busy are you? Is Vienna busy?
“Not only is she busy, but Bonaparte is in Schönbrunn, and the count, our dear Count Vrbna, goes to him for orders.”
Bolkonsky, after the fatigue and impressions of the journey, the reception, and especially after dinner, felt that he did not understand the full meaning of the words he heard.
“Count Lichtenfels was here this morning,” Bilibin continued, “and showed me a letter in which the French parade in Vienna is described in detail. Le prince Murat et tout le tremblement... [Prince Murat and all that...] You see that your victory is not very joyful, and that you cannot be accepted as a savior...
- Really, it doesn’t matter to me, it doesn’t matter at all! - said Prince Andrei, beginning to understand that his news about the battle of Krems really had little importance in view of such events as the occupation of the capital of Austria. - How was Vienna taken? What about the bridge and the famous tete de pont [bridge fortification] and Prince Auersperg? “We had rumors that Prince Auersperg was defending Vienna,” he said.
“Prince Auersperg stands on this, our side, and protects us; I think it protects very poorly, but it still protects. And Vienna is on the other side. No, the bridge has not yet been taken and, I hope, will not be taken, because it is mined and they have ordered it to be blown up. Otherwise, we would have been in the mountains of Bohemia long ago, and you and your army would have spent a bad quarter of an hour between two fires.
“But this still does not mean that the campaign is over,” said Prince Andrei.
- And I think it’s over. And so the big caps here think, but they don’t dare say it. It will be what I said at the beginning of the campaign, that it is not your echauffouree de Durenstein, [the Durenstein skirmish] that gunpowder will decide the matter, but those who invented it,” said Bilibin, repeating one of his mots [words], loosening his skin on the forehead and pausing. – The only question is what the Berlin meeting of Emperor Alexander with the Prussian king will say. If Prussia enters into an alliance, on forcera la main a l "Autriche, [they force Austria] and there will be war. If not, then the only question is to agree on where to draw up the initial articles of the new Campo Formio. [Campo Formio.]
– But what extraordinary genius! - Prince Andrei suddenly cried out, squeezing his small hand and hitting the table with it. - And what happiness is this man!
- Buonaparte? [Buonaparte?] - Bilibin said questioningly, wrinkling his forehead and thereby making it felt that now there would be an un mot [word]. - Bu onaparte? - he said, emphasizing especially the u. “I think, however, that now that he is prescribing the laws of Austria from Schönbrunn, il faut lui faire grace de l"u [we must rid him of i.] I decisively make an innovation and call it Bonaparte tout court [simply Bonaparte].
“No, no joke,” said Prince Andrei, “do you really think that the campaign is over?”
- That's what I think. Austria was left in the cold, and she was not used to it. And she will repay. And she remained a fool because, firstly, the provinces were ruined (on dit, le Orthodox est terrible pour le pillage), [they say that the Orthodox is terrible in terms of robberies,] the army was defeated, the capital was taken, and all this pour les beaux yeux du [for the sake of beautiful eyes,] Sardinian Majesty. And therefore - entre nous, mon cher [between us, my dear] - I instinctively hear that we are being deceived, I instinctively hear relations with France and projects for peace, a secret peace, separately concluded.

MOVEMENTS (in biology)- one of the manifestations of life activity, providing the possibility of active interaction between the constituent parts of the organism and the whole organism with the environment.

D. are presented in various forms interaction of the organism with the environment, interconnected processes occurring in the internal environment at the cellular, tissue, organ and system levels.

Thus, smooth muscles provide tone and wave-like contractions of blood vessels, stomach, intestines, uterus, etc. D. fluids in the body (transport of blood and lymph through vessels, movement of interstitial fluid) ensure the processes of digestion and absorption, the optimal level of metabolism.

The activity of all these mechanisms is aimed at maintaining homeostasis of the internal environment of the body (see Homeostasis) and stability during the unfolding of processes occurring in organs and systems.

The emergence of D. physiology as a section of general physiology that studies the mechanisms of activity of skeletal muscles, as a result of which D. is produced, is associated with the appearance in the 19th century. various ways of registering it using sensors (see) and photography [E. Marey, Muybridge (E. Muybridge)]. The beginning of physiol, human D.'s research is a detailed study of walking conducted by E. Weber and W. Weber. The development of the physiology of D. was significantly influenced by the discovery of the effect of electrical stimulation of various parts of the cerebral cortex [Fritsch and Hitzig (G. Fritsch, E. Hitzig)], the possibility of performing D. by animals deprived of hemispheres. Of greater importance was the identification of postural reflexes by C. Sherrington and the study of reflex mechanisms for regulating posture and balance carried out by R. Magnus. A serious influence on the understanding of the physiology of D. was exerted by the ideas of N.A. Bernstein on the coordination of D. and the work of R. Granit on the central regulation of the proprioceptive apparatus.

D., characteristic of most animals and humans, are the result of contraction of skeletal muscles, ensuring the maintenance of posture (see), movement of links or the entire body in space. The function of vision, facial expressions, and speech are provided by specific forms of D. When classifying D., they take into account the nature of the achieved position of body parts (for example, flexion, extension, etc.), the functional meanings of D. (for example, indicative, protective, etc.) or their mechanical properties (e.g. rotational, ballistic, etc.).

In modern physiology, great importance has been attached to the factor of activity in the behavior of not only humans, but also animals. In humans, D. are continuously controlled by all brain activity aimed at performing a particular task and modeled in successive muscle contractions. This form of activity is called voluntary, or conscious, D., and the coordinated activity of various muscle groups during the implementation of a muscle skill is D. coordination. Coordination of movements is important for the manifestation of a person’s agility, strength, speed and endurance and their interrelation.

Motor reactions can be simple - unconditioned reflex reactions to pain, light, temperature and other stimuli, and complex - a series of sequential movements aimed at solving a specific motor task (see Motor reactions). An example of the latter can be locomotion, i.e. movements of the musculoskeletal system that ensures human movement in space (for example, running, walking, etc.).

The process of formation and regulation of motor reactions is associated with both peripheral and central physiological mechanisms.

The reticular formation of the brain stem can exercise both diffuse activating and inhibitory influences and differentiated control of motor activity. These influences, along the ascending and descending pathways of the reticular formation (see), enter both the motor area of ​​the cerebral cortex and the motor centers of the spinal cord.

Analyzers (see) play a major role in the formation and implementation of motor skills. The proprioceptive analyzer provides the dynamics and relationship of muscle contractions. It is involved in the spatial and temporal organization of the motor act (see Proprioceptors). The vestibular analyzer (see) interacts with the motor analyzer during the formation and implementation of a motor skill, when changing the position of the body in space. The auditory analyzer (see) provides the rhythmic organization of muscle contractions, and the visual analyzer (see) provides the spatial dynamics of muscle activity. All types of D., characteristic of a living organism and determining its vital activity, occur in the unity and struggle of opposing processes of spending and restoring the bioenergetic and structural potentials of the body. I.P. Pavlov was the first to point out that the process of inhibition contributes to the restoration of the spent irritable substance.

In living organisms, the recovery process is associated in the vast majority of cases with self-regulation mechanisms at the systemic, organ, tissue and cellular levels (see Self-regulation of physiological functions). Consumption is a natural stimulant of recovery and therefore functional overload - important means management of recovery processes.

There are several types of recovery: periodic, associated with biorhythms in the human and animal body; at the same time, the interaction of endogenous and exogenous rhythms (day and night, seasons, etc.) has a profound influence on this process (see Biological rhythms); pre-working, arising through the mechanism of a conditioned reflex during the pre-start state and characterizing “readiness for action”, according to F. A. Bainbridge, or “preventive readiness”, according to A. A. Ukhtomsky; current - occurs during work due to regulatory coordination processes and adaptation-trophic influences c. n. With.; after work, associated with the development of inhibitory processes in the c. n. With. and elimination of changes in the chemistry of the internal environment of the body that occurred during work; During post-work recovery, a constructive period is formed, during which the accumulation of structural and bioenergetic resources occurs - the so-called. super-recovery.

The characteristics of stability and reliability of D. at varying degrees of functional activity of the body, as well as adaptive and compensatory systems, are an important basis for the life of the organism as a whole.

Reliability is determined by a number of features in the structural and functional hierarchy of D. regulation systems at all levels.

Akinez

The term “akinesis” is used to refer to various manifestations of immobility in the motor sphere in humans and animals. Less pronounced degrees of immobility are designated as hypokinesia (see). In medical practice, akinesia refers to conditions manifested by a decrease in the dynamics of D. in general, a general drop in the level of motor functions and motor initiative.

The picture of akinesis is most typical in the akinetic-rigid form of parkinsonism (see). In such cases, the patient lies motionless or sits in bed, his motor skills are extremely limited, he experiences a state of general stiffness, voluntary movements are slowed down, prone to freezing; the face is inexpressive, mask-like. Motor delay changes the patient's handwriting; he writes slowly in small handwriting (micrography).

In the origin of akinesia, apparently, a peculiar increase in the tone of the muscles of the body and limbs and the development of rigidity in them, i.e. plastic hypertension, is important. It differs from pyramidal spasticity in that it occurs and persists during all phases of muscle stretching.

Akinesis develops with lesions of the deep structures of the brain (substantia nigra, reticular formation of the brain stem, globus pallidus, frontal-subcortical connections), which control extrapyramidal motor activity and muscle tone. Electrophysiol, studies indicate a significant prolongation of the time of conduction of excitations from the cerebral cortex to the segmental apparatus of the spinal cord.

It has been established that the low level of functional activity of the deep areas of the brain during akinesis is caused not only by organic changes in these structures, but also by disruption of biochemical processes in them. There is a parallelism between the severity of akinesis and a drop in dopamine concentration in striatal formations and the substantia nigra of the brain stem. Dopamine deficiency reduces the activity of dopaminergic neurons in the subcortical nodes and leads to a “disorder” of motor programs.

In patients with akinesis, under the influence of various stressful conditions, motor crises may occur, which are collectively called “paradoxical kinesia”; the immobilized patient disinhibits, becomes active, and is able to perform complex movements (running, walking, games, etc.), but then again falls into a state of akinesis. Attacks of paradoxical kinesia should be considered as periodic activation of cortical motor areas with suppression of the pathological dominant.

A special form of the disease is the so-called. akinetic mutism. It can occur with damage to the oral parts of the brain stem and reticular formation, limbicoreticular complex; occurs subacutely or chronically. The patient is in a state of akinetic mutism in the phase of inhibition, lies in bed motionless, does not follow commands, there are no emotions, speech is whispered, barely audible. Sometimes slight eye movements are observed. The EEG shows significant depression of the alpha rhythm. The state of global inhibition is sometimes interrupted by convulsive crises and hyperkinesis (see Myoclonus, Torsion dystonia, etc.).

The lethal outcome in these conditions may be due to impaired vital functions and the development of respiratory and cardiovascular failure.

A state of immobility can also accompany other diseases of the nervous system, for example, in patients with neuroses as a result of fixation of painful conditions and obsession in the motor sphere, phobias, etc. Hysterical manifestations of immobility are called “symptoms of imaginary death” by analogy with the freezing of animals in response to a life-threatening situation. Significant inhibition of motor reactions often complements the picture of psychosis (schizophrenia, manic-depressive psychosis, senile psychosis).

Akinesia can develop as a result of intoxication of the subcortical nodes with long-term use of neuroleptics (aminazine, reserpine, stellazine, etc.) - the so-called. akinetic form of aminazine parkinsonism, reserpine parkinsonism, etc.

Akinesia algera- painful immobility. There is no movement due to significant pain, although there are no noticeable signs of organic damage; this may be associated with diffuse muscle diseases (eg, myositis, dermatomyositis, etc.). Patients do not leave their beds for months. All cases of akinesia of this form require careful clinical physiology and analysis.

In the clinic, D. coordination disorders usually mean such states of motor activity that are characterized by a mismatch in the work of muscles - synergists (Fig. 1), agonists and antagonists, a violation of the dynamic stabilization of D. and untimely execution.

The leading symptoms of impaired coordination D. (discoordination) are ataxia, dyssynergia, dysmetria (see Ataxia, Cerebellum).

D. coordination disorders are caused by various organic processes in the c. n. pp.: tumors, abscesses, encephalitis, arachnoiditis, demyelination, hemorrhages, ischemia, degeneration, etc. Damage to the cerebellar structures leads to disruption of support reflexes, decreased muscle tone and the appearance of static ataxia. The patient walks with his legs wide apart, staggers when walking from side to side (“drunken gait”), and balances like a person walking on a tightrope. During walking, a picture of asynergy is noted (Fig. 2) - there is no normal combined flexion of the legs in the hip, knee and ankle joints, the legs move in front of the body - trunk ataxia, etc. Maintaining a vertical posture of the patient due to the difficulty of maintaining balance is impossible, there is a tendency to body vibrations and falling - the so-called. Romberg's symptom (see Romberg's symptom).

Disorders of the functions of the cerebellar hemispheres entail the appearance of dynamic incoordination: each D. of the patient becomes uncoordinated, loose, and sweeping. Dynamic ataxia manifests itself on the side of the cerebellar lesion. The patient cannot outline the space in the form of a circle with his hand (a broken, zigzag line appears). During the heel-knee test, the leg, swinging stepwise, touches not the knee, but the shin of the other leg. The index finger fails to accurately hit the tip of the nose, the noses become disproportionate, swaying and sweeping appear, and intentional trembling is added (finger-nose test - Fig. 3).

Lack of stability in D. affects the patient’s handwriting: the line becomes disproportionate, the letters are uneven and large.

As a result of the close connection of the cerebellum with the cortex (frontopontine-cerebellar pathway and other pathways), in some cases there is a tendency for regression of cerebellar disorders due to cortical functions. Static and dynamic ataxia often appear with damage to the brain stem, where a number of centers responsible for postural tone and coordination of the brain are located (inferior olive, reticular formation, cerebellar peduncles, etc.). Such disorders with the presence of muscle hypotonia are most pronounced in lesions in the lateral parts of the pons and medulla oblongata. The participation of the red nucleus, the superior cerebellar peduncle is manifested by tremors, taxia, increased postural reflexes and support reactions on the side opposite to the lesion. With cortical disorders, coordination disorders also occur on the heterolateral side. The most significant coordination disorders are in patol, processes affecting the frontal and temporal parts of the brain. The phenomena of discoordination D. accompany spinal processes and occur in cases where afferentation from the proprioceptors of muscles and joints to the cerebellum along the posterior cords is disrupted. The patient's gait becomes unsteady and unsteady. Hypotonia of the muscles leads to hyperextension of the joints. When visual control is turned off (in the dark and with eyes closed), ataxia increases sharply (tabes spinal cord, Friedreich's disease).

Mechanisms of deafferentation (see) underlie ataxias in multiple lesions of peripheral nerves - polyradiculoneuritis (see Polyneuritis), in which the transmission of sensitive signals to the cerebellum is blocked. Muscle tone decreases, gait and movement become uncertain and shaky (peripheral tabes, alcoholic pseudotabes). This ataxia is accompanied by signs of neuromuscular damage - pain, sensitivity disorders, decreased proprioceptive reflexes, etc.

Adiadochokinesis

In a healthy person, coordination mechanisms ensure the implementation of successive opposite actions. This normal function is associated with reciprocal innervation, which prepares a change in phase reactions in the agonist-antagonist system.

When the cerebellum is damaged (tumors, multiple sclerosis, dystrophic processes, hemorrhages, etc.), the patient becomes unable to carry out rhythmic, opposite in sign D. at a fast pace, the so-called. adiadochokinesis (a type of cerebellar asynergia). Adiadochokinesis is detected using various wedges, tests, which are based on changing simple Ds at a fast pace. In particular, the patient, at the request of the doctor, performs rapid (or with increasing tempo) pronation and supination of the hands (synchronously). With adiadochokinesis, the change of such D. is difficult, slowed down, the rhythm of D. is disturbed, and their disproportion is noted. Adiadochokinesis is found on the side of the cerebellar lesion. The presence of cerebellar damage is also confirmed by the combination of adiadochokinesis with other symptoms of cerebellar incoordination.

Grotesque manifestations of coordination disorders in a certain combination - disorders of standing and walking with complete preservation of other systems and functions (see Astasia-abasia) - are interpreted clinically as manifestations of motor neurosis (hysteria).

Movements in the elderly and old age. Elderly and old people are characterized by changes in the movements. There is a slowdown in tempo, a violation of rhythm and accuracy, a decrease in the amplitude and plasticity of the movements. Muscle rigidity increases, a slight tremor of the hands and head appears (see Trembling), the ability to simultaneously perform several movements at the same time is limited, and it becomes difficult to perform thin D., handwriting changes. The mechanism of these changes is largely related to the insufficiency of the extrapyramidal system.

EMG data (increase in reciprocity and adequacy coefficients, unclear separation of “packs” of biocurrents from current-free areas, changes in resting EMG) indicate changes in the central mechanisms of coordination of D.

Age-related changes in static and dynamic coordination of movements

Age-related changes static and dynamic coordination of D. have a complex mechanism and can be understood by taking into account the functional and structural changes occurring in the cortical part of the motor analyzer, the cerebellum, and subcortical-stem formations. Peripheral mechanisms are also involved in the disturbance of locomotor coordination. Age-related changes in the muscular and ligamentous-articular apparatus lead not only to limitation of movement, but also to a weakening of tendon reflexes, which are important in the formation of plasticity of movement. With old age, the latent period of tendon reflexes increases due to an increase in the central time of the reflex and a slowdown in the conduction of excitation along motor nerves and neuromuscular junctions.

In old and senile age, the formation of new motor skills becomes difficult, the structure of the ergographic curve of voluntary muscle activity changes (see Ergography), which is determined by a violation of the dynamics of nervous processes - a weakening of the inhibition process and inertia of the excitatory process.

Bibliography: Alexander R. Biomechanics, trans. from English, M., 1970, bibliogr.; Anokhin P.K. Internal inhibition as a problem of physiology, M., 1958; aka, Biology and neurophysiology of the conditioned reflex, M., 1968, bibliogr.; Arshavsky I. A. Physiological mechanisms of some basic patterns of ontogenesis, Usp. fiziol, sciences, vol. 2, no. 4, p. 100, 1971, bibliogr.; Bernshtein N. A. On the construction of movements, M., 1947; o N e, Essays on the physiology of movements and physiology of activity, M., 1966, bibliogr.; Granit R. Fundamentals of movement regulation, trans. from English, M., 1973, bibliogr.; Luria A. R. Higher nervous functions of man, M., 1969; Principles of systemic organizations of functions, ed. P.K. Anokhina, p. 5, M., 1973; Development of contractile function of the muscles of the musculoskeletal system, ed. L. G. Magazanika and G. A. Nasledov, L., 1974; Physiological problems of detraining, ed. A. V. Korobkova, M., 1970; Physiology of movements, edited by V. S. Gurfinkel, L., 1975; X i n d R. Animal behavior, trans. from English, M., 1975; Chauvin R. Animal behavior, trans. from French, M., 1972.

Pathology- Wartenberg R. Diagnostic tests in neurology, trans. from English, M., 1961; Milner P. Physiological psychology, trans. from English, M., 1973; Multi-volume guide to neurology, ed. G. N. Davidenkova, vol. 2, p. 110, M., 1962; Petelin L. S. Extrapyramidal hyperkinesis, M., 1970; Fudel-Osipova S.I. Aging of the neuromuscular system, Kyiv, 1968, bibliogr.

A. V. Korobkov; L. S. Petelin (neur.), V. A. Polyantsev (system analysis), V. V. Smolyaninov (biomechanical foundations of D.), S. A. Tanin (geront.).

One of the most important properties of all living organisms is the ability to move. Multicellular animals are especially complex and varied in their movements.

Movement of single-celled organisms

Single-celled organisms can move in different ways. Many bacteria, single-celled animals and protozoa move using flagella. There can be from one to several thousand. Flagella move, as a rule, in waves; Ciliates move in space with the help of cilia. They are more than 10 rai shorter than flagella, their movements are similar to the oscillations of a pendulum. the common one moves with the help of temporary outgrowths - pseudopods. It seems to flow along the bottom. When releasing pseudopods, the amoeba moves at a speed of 0.2 mm per minute.

Movement of plants and fungi

Plants and, unlike animals, do not move in space. However, this does not mean that they do not make movements. Most movements of mushrooms and plants are the result of their growth. The growth hormone produced in plant cells at the top is very sensitive to light, so the shadow side grows faster than the illuminated side and the stem bends towards the light. In plants, some movements occur in response to environmental factors. Thus, the main stem grows vertically downward under the influence of gravity, and the main stem grows upward under the influence of light. The leaves have well-defined movements towards the light: the plate, especially in shading conditions, is located perpendicular to the sun's rays.

Through movement, plant organs can make maximum use of light, moisture and nutrients.

Animal movement

Unlike plants and fungi, most multicellular animals actively move in space. Various methods of movement are used to search for and consume food and escape from predators. That is why, in the process of historical development, they developed a complex musculoskeletal system. The basis of such a system is the skeleton. In vertebrates, the skeleton is internal, it is built from bone and cartilaginous tissue. The chipped parts are connected motionlessly or using joints. The skeleton serves as a place for muscle attachment. When muscles contract, parts of the skeleton act as levers, which leads to
to various movements. The coordinated work of muscles, their contraction and relaxation is ensured by the nervous system.

For active movement in various environments, animals have developed a variety of limbs. Aquatic animals move with the help of fins (fish) or flipper-like limbs (fur seals, walruses). Soil animals dig tunnels with the help of digging forelimbs adapted for this purpose. Most animals living in the ground-air environment have special motor limbs. With their help, they perform various movements: walk, run, crawl, jump. Some animals are able to fly. The wings of birds and bats are modified forelimbs. The wings of other insects are outgrowths of the integument.