The main directions of development of modern biophysics. Levels of biophysical research. Lectures on biophysics Guys that we were asked on micro biophysics

INTRODUCTION

"The logic of nature is the most accessible and most useful logic for children."
K. D. Uminsky

In this manual, which presents a description of work experience, an attempt is made to consider the main directions and features of the connection between school courses in physics and biology and to outline possible ways and forms of strengthening this connection.
The main directions of this work are as follows: to acquaint students with the physical methods of research and influence, which are widely used in biology and medicine, with wildlife physics, with some elements of bionics.
A large number of biophysical examples can be selected for almost all sections of the physics course (which is what we did, see the appendix), but it is advisable to use them only partially, along with technical examples and examples from inanimate nature.
The main goal of attracting biophysical examples is to achieve a better assimilation of the physics course. Biophysical material should be directly related to the curricula of courses in physics and biology and reflect the most promising directions in the development of science and technology.
Three main directions for the selection of biophysical material can be indicated.
The first direction has the goal of showing students the unity of the laws of nature, the applicability of the laws of physics to a living organism.
The second direction corresponds to familiarization with the physical methods of influence and research, which are widely used in biology and medicine. In the secondary school physics course, students are introduced only to optical instruments (magnifying glass, microscope), using X-rays and "tagged atoms". However, already in an ordinary city clinic, each person is faced with a large number of physical methods for examining his body - blood pressure is measured, biopotentials of the heart are recorded, etc., which are not considered at school.
The third direction involves familiarizing students with the ideas and some results of bionics. For example, when studying vibrations, students are told that the auditory organ of a moth perceives sound vibrations in the frequency range from 10 to 100 kHz and makes it possible to detect the approach of a bat (for it, a moth is a favorite food) at a distance of 30 m. These "achievements" of wildlife are higher than the results obtained in the field of echo sounders, ultrasonic radars, flaw detectors and even radars. There are many such examples. However, it should be emphasized that bionics aims not to blindly imitate biological systems, but to reveal the principles of their construction.

Chapter I
USE OF BIOPHYSICAL MATERIAL IN PHYSICS LESSONS

Ways of familiarizing students with biophysical material do not fundamentally differ from ways of familiarizing them with elements of technology. Physics is the basis of technology; on the other hand, physics is widely used for research in biology and helps to understand the features of the structure and life of biological objects.
Already at the very first lessons, the children learn that all natural sciences use the laws of physics. This idea needs to be clarified and expanded. At the first acquaintance with the subject - physics, it is desirable to show students the applicability of its laws to the life of humans and plants, birds, fish, etc. To do this, you can compare the flight of birds, insects and airplanes, talk about the location in the animal world in the field of inaudible sounds. You can, for example, talk about the fact that the study of the structure of the body of a mole helped engineers create an earth-moving machine, and observations of dolphins and fish help improve submarines. Leonardo da Vinci's classical observations of the flight of birds and the design of their wings and the use of these ideas by modern engineers in the design of aircraft, flywheels and rockets are known. It is important that the idea is imprinted in the minds of students from the first lessons that physics is the key to understanding the phenomena of both inanimate and living nature.
When presenting new material in physics, it is best to present illustrative biophysical information to the teacher himself. It can be both numerical data characterizing living organisms, and a description of research methods used in biology, and brief data on medical or biological equipment.
The presentation of new material can be alternated with a conversation, especially in the lower grades. The teacher refers to the life experience of students, to the information that they received while studying in elementary school, in the lessons of botany, geography and other related disciplines. Solving problems in the physics of living nature can play an important role in familiarizing oneself with the elements of biophysics. For example, using a table of sports records for running, skating, etc., you can find average speeds, practice converting speed units from one system to another.
When repeating the past, it is also possible to involve biophysical material. We used this form of work after studying some topics, at the end of the school year and when repeating before the final exams. Let's name some topics of review repetition: mechanics in wildlife, electricity and wildlife, optics and life, the influence of electromagnetic fields on animals and plant organisms.
It is expedient to present a number of biophysical issues using fragments from some films and filmstrips, drawings, diagrams and tables, as well as visual aids available in the biology classroom.
Most often, physics teachers can get only a very limited range of equipment in the biology classroom (microscope, models of the eye, ear; corresponding tables). Meanwhile, this is far from all the equipment available in biology classrooms that can be usefully used in the study of physics. Already during our first biophysical evening “Physics and Medicine”, we used the following equipment from the biology room: a device for measuring lung vital volume, a device for measuring blood pressure, eye and ear models, dynamometers for measuring muscle strength.
Later, in the practice of our work, introducing students to the elements of biophysics, we also tried to use the equipment of the biology classroom for this purpose: “Tables on human anatomy and physiology” by A. N. Kabanov, “Mnr animals” - a series of multi-color tables A. A. Yakhontov, herbariums and collections of butterflies, dragonflies, beetles, turtles, etc. It is also useful to show some educational films and filmstrips on biology.
In the future, we will indicate where and what visual aids and technical means can be used, as well as what visual aids the students themselves can make.

§ 1. Elements of biophysics in the study of mechanics

Movement and forces
When studying the topic “Movement and Forces” in grade VI, students can be introduced to the speeds of movement of various living beings. A snail crawls about 5.5 m in 1 hour. A turtle moves at a speed of about 70 m/h. A fly flies at a speed of 5 m/s. The average walking speed is about 1.5 m/s, or about 5 km/h. An infantry military unit can move at speeds up to 7 km/h. The horse is able to move at speeds from 6 to 30 km / h and above.
Of the animals of the middle lane, the hare runs the fastest, its speed reaches 50 - 60 km / h. Slightly inferior to him is the wolf, which can run at speeds up to 45 km / h. ;
Many fish move at an average speed of about 4 km / h, but some of them are capable of reaching much higher speeds: for example, swordfish can reach speeds of up to 90 km / h.
It is also interesting to consider the figures given in the table of fish movement speeds.
Here it is very important to pay attention to the estimation of fish speeds in centimeters per second, as well as in body lengths per second. According to these data, the trout turns out to be the fastest, although the absolute value of its speed is relatively small.
Using the speed data of different representatives of the animal world, it is possible to solve various kinds of problems. Let's take a look at some of them.
The speed of movement of the cochlea is 0.9 mm/sec. Express this speed in cm/min, m/h.
The peregrine falcon, chasing prey, dives at a speed of 300 km / h. What distance does it travel in 5 seconds?
1 The speed of many living beings is expressed by a special value equal to the number of lengths of their body that they move per second
Carrier pigeon flight speed 1800 m/min. Express this value in km/h. What is the distance traveled by a dove in 3 hours of flight? Is it possible to overtake a pigeon in a car with an average speed of 60 km/h?
It is known that the average oak growth rate is about 30 cm/year. How old is a tree 6.3 m high?
Soviet athlete Vladimir Kuts ran 5000 m in 815 seconds. Determine its speed in km/h.

Tel weight Density
When getting acquainted with the concept of "body mass" and when compiling tasks for determining the density of a substance and the volume occupied by a body, we used some additional tabular data (Table 2).
Example. Determine the mass of birch wood if its volume is 5 m3.
Example. What is the mass of linseed oil that occupies a volume of 5 liters?
Example. Determine the volume of dry bamboo if its mass is 4800 kg.

Gravity. Body weight
When studying this topic, you can conduct the following training work. The masses of different mammals are given: whale - /0000 kg, elephant - 4000 kg, rhinoceros - 2000 kg, bull - 1200 kg, bear - 400 kg, pig - 200 kg, human - 70 kg, wolf - 10 kg, hare - 6 kg . Find their weight in newtons.
The same data can be used to graphically depict forces.
Some more interesting information can be provided along the way.
The largest animals belong to the class of mammals, of which the blue whale is especially striking in size and weight. For example, one of the whales caught reached a length of 33 m and weighed 1500 kn, which corresponded to the weight of 30 elephants or 150 bulls. The largest modern bird is the African ostrich, reaching 2.75 m in height, 2 liters in length (from the tip of the beak to the end of the tail) and weighing 75 kg. The smallest birds are hummingbirds. Hummingbirds of one of the species have a mass of about 2 g, a wingspan of 3.5 cm.
Forces of friction and resistance.

Friction in living organisms
A large amount of biophysical material can be drawn upon in stating the problem of friction forces. It is known that liquids used to reduce friction (oil, tar, etc.) always have a significant viscosity. It is the same in a living organism: the fluids that serve to reduce friction are at the same time very viscous.
Blood, for example, is a liquid that is more viscous than water. When moving through the vascular system, it experiences resistance due to internal friction and friction on the surface of the vessels. The thinner the vessels, the greater the friction and the more the blood pressure drops.
Low friction in the joints is due to their smooth surface, their lubrication with synovial fluid. Saliva plays the role of lubrication when swallowing food. The friction of muscles or tendons against the bone is reduced due to the release of a special fluid by the bags in which they are located. The number of such examples can be continued.
Significant friction is essential for the working surfaces of the organs of motion. A necessary condition for movement is a reliable "coupling" between the moving body and the "support". Grip is achieved either by points on the limbs (claws, sharp edges of hooves, horseshoe spikes), or by small irregularities, for example, bristles, scales, tubercles, etc. Significant friction is also necessary for grasping organs. Their shape is interesting: these are either tongs, exciting
an object from two sides, or strands that envelop it (if possible, several times). The hand combines the action of forceps and full coverage from all sides; the soft skin of the palm adheres well to the roughness of objects that need to be held.
Many plants and animals have various organs that serve for grasping (the antennae of plants, the elephant's trunk, the tenacious tails of climbing animals, etc.). All of them have a shape that is convenient for winding and a rough surface to increase the coefficient of friction (Fig. 1).
Among living organisms, adaptations are common (wool, bristles, scales, spikes located obliquely to the surface), due to which friction is small when moving in one direction and large when moving in the opposite direction. The movement of the earthworm is based on this principle. The bristles, directed backwards, freely pass the body of the worm forward, but inhibit the reverse movement. When the body is lengthened, the head part moves forward, while the tail part remains in place, while contracting, the head part is delayed, and the tail part is pulled up to it.
A change in resistance when moving in different directions is also observed in many waterfowl. For example, the swimming membranes on the legs of ducks or geese are used like oars. When moving the foot back, the duck rakes water with a straightened membrane, and when moving forward, the duck moves its fingers - the resistance decreases, as a result of which the duck moves forward.
The best swimmers are fish and dolphins. The speed of many fish reaches tens of kilometers per hour, for example, the speed of a blue shark is about 36 km/h. Fish can develop such speed due to the streamlined shape of the body, the configuration of the head, which causes low drag1.
1 Reduction of resistance due to the streamlined shape of the body of fish can be illustrated on stuffed perch, pike; you can also show the "Shark" table from A. A. Yakhontov's series "The World of Animals".
The interest of specialists was attracted by the ability of dolphins to move in the water without much effort at high speed (near the bow of the ship 55 - 60 km / h, freely swimming - 30 - 40 km / h). It was noted that around a moving dolphin, only a slight jet (laminar) movement occurs, which does not turn into a vortex (turbulent).
Research has shown that the secret of the dolphin's "anti-turbulence"
hidden in his skin. It consists of two layers - an outer, extremely elastic, 1.5 mm thick, and an inner, dense, 4 mm thick.
Between these layers there are outgrowths, or spikes. Below are densely woven fibers, the space between which is several centimeters filled with fat.
This skin acts as an excellent damper. In addition, the dolphin's skin constantly has a thin layer of a special "lubricant" produced by special glands. This reduces the friction force.
Since 1960, artificial damping coatings have been produced, similar in their properties to “dolphin skin”. And already the first experiments with a torpedo and a boat sheathed in such leather confirmed the possibility of reducing water resistance by 40 - 60%.
Fish are known to move in schools. Small marine fish walk in a flock, similar in shape to a drop, while the resistance of water to the movement of the flock is the least.
Many birds gather in a chain or school during long-distance flights. In the latter case, the stronger bird flies ahead, its body cutting through the air like the keel of a ship cuts through the water. The rest of the birds fly in such a way as to keep the sharp angle of the school; they maintain the correct position relative to the lead bird instinctively, as it corresponds to a minimum of resistance forces.
planning flight. Gliding flight is quite often observed in both the plant and animal kingdoms. Many fruits and seeds are equipped with either bundles of hairs (dandelion, cotton, etc.), acting like a parachute, or supporting planes in the form of processes and protrusions (conifers, maple, birch, linden, and many umbrella ones). Some fruits and seeds equipped with "gliders" are shown in Figure 2, a.
Plant gliders are in many ways even more advanced than man-made ones. They lift a much larger load compared to their weight, in addition, they are more stable.
The structure of the body of flying squirrels, coleopterans, and bats is interesting (Fig. 2b). They use their membranes to make big jumps. So, flying squirrels can jump distances up to 20 - 30 m from the top of one tree to the lower branches of another.

Pressure of liquids and gases
The role of atmospheric pressure in the life of living organisms.
A human body, whose surface, with a mass of 60 kg and a height of 160 cm, is approximately equal to 1.6 m2, is affected by a force of 160 thousand n, due to atmospheric pressure. How does the body withstand such a huge load?
This is achieved due to the fact that the pressure of the fluids filling the vessels of the body balances the external pressure.
Closely related to this issue is the possibility of being underwater at great depths. The fact is that the transfer of the body to another high-altitude level causes a breakdown of its functions. This is due, on the one hand, to the deformation of the walls of the vessels, designed for a certain pressure from the inside and outside. In addition, when the pressure changes, the rate of many chemical reactions also changes, as a result of which the chemical balance of the body also changes. With an increase in pressure, there is an increased absorption of gases by body fluids, and with a decrease in pressure, the release of dissolved gases. With a rapid decrease in pressure due to the intense release of gases, the blood boils, as it were, which leads to blockage of blood vessels, often fatal. This determines the maximum depth at which diving operations can be carried out (as a rule, not lower than 50 m). The lowering and raising of divers must be very slow so that the release of gases occurs only in the lungs, and not immediately in the entire circulatory system.
It is interesting to further analyze in more detail the principle of operation of organs acting due to atmospheric pressure.
The work of organs acting due to atmospheric pressure. sucking mechanism. Muscular effort (contraction of the muscles of the tongue, palate, etc.) creates a negative pressure (rarefaction) in the oral cavity, and atmospheric pressure pushes a portion of the liquid there.
The mechanism of action of various kinds of suction cups. Suckers have the form of either a hemispherical bowl with sticky edges and highly developed muscles (the edges are pressed against the prey, then the volume of the sucker increases; suckers of leeches and cephalopods can serve as an example), or they consist of a row of skin clutches in the form of narrow pockets. The edges are applied to the surface on which to hold; when you try to pull the suction cup, the depth of the pockets increases, the pressure in them decreases, and atmospheric pressure (for aquatic animals, water pressure) presses the suction cup to the surface more strongly. For example, a sticky fish, or remora, has a sucker that occupies almost the entire length of its head. This fish sticks to other fish, stones, as well as boats and ships. It sticks so firmly that it is easier to break it than to unhook it, thanks to which it can serve as a kind of fishing hook.
Figure 3 shows a club - the end of one of the two longest trapping squid tentacles, it is densely seated with suckers of various sizes.
In a similar way, the suckers of the pork tapeworm are arranged, with the help of which this tapeworm clings to the wall of the human intestine.
The structure of these suckers can be shown on a wet tapeworm preparation, which is available in the biology room.
Walking on sticky soil. The influence of atmospheric pressure is very noticeable when walking on viscous soil (the suction effect of a swamp). When the leg is raised, a rarefied space forms under it; excess external pressure prevents the leg from rising. The force of pressure on the leg of an adult Fig. 3.
can reach 1000 k. This is especially evident when walking a horse, whose hard hoof acts like a piston.
Mechanism of inhalation and exhalation. The lungs are located in the chest and are separated from it and from the diaphragm by an airtight cavity called the pleural cavity. With an increase in the volume of the chest, the volume of the pleural cavity increases, and the air pressure in it decreases, and vice versa. Since the lungs* are elastic, the pressure in them is regulated only by the pressure in the pleural cavity. When inhaling, the volume of the chest increases, due to which the pressure in the pleural cavity decreases (Fig. 4.6); this causes an increase in lung volume by almost 1000 ml. At the same time, the pressure in them becomes less than atmospheric, and air rushes through the airways into the lungs. When exhaling, the volume of the chest decreases (Fig. 4c), due to which the pressure in the pleural cavity increases, which causes a decrease in lung volume. The air pressure in them becomes higher than atmospheric pressure, and air from the lungs rushes into the environment.
With a normal calm breath, about 500 ml of air is inhaled, the same amount is exhaled during a normal exhalation, and the total volume of air in the lungs is about 7 l.
1 To explain the mechanism of inhalation - exhalation, a model diagram of the chest cavity, available in the biologin office, can be used. Here, a water spirometer can be demonstrated, which serves to measure the vital capacity of the lungs. The film "The Structure and Functions of the Respiratory Organs", released by the Leningrad Educational Film Studio in 1964, can also be shown when studying this topic.
The heart is a pump.
The heart is an amazing pump that works non-stop throughout a person's life.
It pumps 0.1 liters of blood in 1 second, 6 liters in a minute, 360 liters in 1 hour, 8640 liters in one day, more than 3 million liters in a year, and about 220 million in 70 years of life. , l.
If the heart did not pump blood through a closed system, but pumped it into some kind of reservoir, then it would be possible to fill a pool 100 m long (PC) m wide and 22 m deep.
Pufferfish in the struggle for existence. The "application" of gas laws in the life of a kind of fish - a pufferfish is interesting. It lives in the Indian Ocean and the Mediterranean Sea. Her body is densely dotted with numerous spikes - modified scales; when at rest, they are more or less close to the body. When danger arises, the pufferfish immediately rushes to the surface of the water and, swallowing air into the intestines, turns into a swollen ball; the spikes rise and stick out in all directions (Fig. 5). The fish keeps near the surface, tipping over with its belly, and part of the body protrudes above the water. In this position, the pufferfish is protected from predators both from below and from above. When the danger has passed, the pufferfish releases air, and its body takes on an omniform form.
Hydrostatic devices in wildlife. Curious prostatic apparatuses exist in wildlife. For example, cephalopods of the nautilus genus live in shells separated by partitions into separate chambers (Fig. 6). The animal itself occupies the last chamber, while the rest are filled with gas. To sink to the bottom, the mollusk fills the shell with water, it becomes heavy and sinks easily. To float to the surface, the nautilus pumps gas into the compartments of the shell; the gas displaces the water and the sink sloshes.
The liquid and gas are under pressure in the shell, which is why the mother-of-pearl house does not burst even at a depth of 4 cm1.hundred meters.
An interesting way of moving sea stars, sea urchins, holothurians, which move due to the difference in hydro-t ytic pressures. The thin, hollow and elastic legs of a starfish swell as it moves. Bodies-pumps under dpnlsipem pump water into them. Water stretches them, they pull forward, stick to the stones. The sucked legs are compressed and pull the starfish forward, then the water is pumped into other legs and the vehicles move on. The average speed of sea stars is about 10 m/h. But on the other hand, full motion damping is achieved here!

Archimedean force
Fish. The density of living organisms inhabiting the aquatic environment differs very little from the density of water, so their weight is almost completely balanced by the Archimedean force. Thanks to this, aquatic animals do not need such massive skeletons as terrestrial ones (Fig. 7).
The role of the swim bladder in fish is interesting. This is the only body part of the fish that has noticeable compressibility; By squeezing the bubble with the efforts of the pectoral and abdominal muscles, the fish changes the volume of its body and thereby the average density, thanks to which it can, within certain limits, regulate the depth of its dive.
Water birds. An important factor in the life of waterfowl is the presence of a thick layer of feathers and down that does not let water through, which contains a significant amount of air; due to this peculiar air bubble surrounding the entire body of the bird, its average density is very low. This explains the fact that ducks and other waterfowl do not submerge much when swimming.
Silver spider. From the point of view of the laws of physics, the existence of a silver spider is very interesting. The silver spider arranges its dwelling - an underwater bell - from a strong web. Here the spider brings air bubbles from the surface, lingering between the thin hairs of the abdomen. In the bell he collects a supply of air, which he replenishes from time to time; thanks to this, the spider can stay under water for a long time.
Aquatic plants. Many aquatic plants maintain an upright position, despite the extreme flexibility of their stems, because large air bubbles are enclosed at the ends of their branches, playing the role of floats.
Water chestnut. A curious aquatic plant is chilim (water prex). It grows in the backwaters of the Volga, in lakes and estuaries. Its fruits (water nuts) reach 3 cm in diameter and have a shape similar to a sea anchor with or without a few sharp horns. This "anchor" serves to keep the young germinating plant in a suitable place. When the chilim fades, heavy fruits begin to form underwater. They could drown the plant, but just at that time swellings form on the petioles of the leaves - a kind of "rescue belt". This increases the volume of the underwater part of the plants; hence the buoyant force increases. This achieves a balance between the weight of the fruit and the buoyancy force generated by the swelling.
Swimming siphonophore. Zoologists call siphonophores a special group of intestinal animals. Like jellyfish, they are free-swimming marine animals. However, unlike the former, they form complex colonies with very pronounced polymorphism*. At the very top of the colony, there is usually an individual, with the help of which the entire colony is kept in the water column and moves - this is a bubble containing gas. Gas is produced by special glands. This bubble sometimes reaches 30 cm in length.
The rich biophysical material of this section makes it possible to conduct lessons with sixth graders in a varied and interesting way.
Let us describe, for example, a conversation in the process of studying the topic “Archimedean force”. Students are familiar with the life of fish, with the characteristics of aquatic plants. They have already familiarized themselves with the action of the buoyant force. Gradually we bring them to an understanding of the role of the law of Archimedes for all creatures in the aquatic environment. We start the conversation by asking questions: why does a fish have a weaker skeleton than creatures living on land? Why don't algae need hard stems? Why does a stranded whale die under its own weight? Such unusual questions in a physics lesson surprise students. They are interested. We continue the conversation and remind the guys that much less force needs to be applied in the water to support a comrade than on the shore (in the air). Summing up all these facts, directing students to their correct interpretation, we bring the children to a far-reaching generalization about the influence of the physical factor (buoyancy force, which turns out to be much greater in the aquatic environment than in the air) on the development and structural features of aquatic creatures and plants.

Newton's laws
Some manifestations of inertia. Ripe pods of leguminous plants, opening quickly, describe arcs. At this time, the seeds, breaking away from the places of attachment, by inertia move tangentially to the sides. This method of seed dispersal is quite common in the plant kingdom.
In the tropical zones of the Atlantic and Indian Oceans, the flight of the so-called flying fish is often observed, which, fleeing from marine predators, jump out of the water and make a gliding flight with a favorable wind, covering distances up to 200 - 300 m at a height of 5 - 7 m. air due to the rapid and strong vibrations of the caudal fin. At first, the fish rushes along the surface of the water, then a strong blow of the tail lifts it into the air. Spread long pectoral fins support the body of the fish like a glider. The flight of fish is stabilized by the tail fins; fish move only by inertia.
Swimming and Newton's third law. It is easy to see that in the process of movement, fish and leeches push water back, while they themselves move forward. A swimming leech drives water back with wave-like movements of the body, and a swimming fish with a wave of its tail. Thus the movement of fish and leeches can serve as an illustration of Newton's third law.
Flight and Newton's third law. Insect flight is based on flapping wings (flapping flight). Flight control is achieved almost exclusively by the wings. By changing the direction of the plane of flapping wings, insects change the direction of movement: forward, backward, flying in one place, turning, etc. Some of the most nimble insects in flight are flies. Omi often makes sharp turns to the side. This is achieved by abruptly turning off the wings of one side of the body - their movement stops for a moment, while the wings of the other side of the body continue to oscillate, which causes a turn to the side from the original direction of flight.
Butterflies-brazh-nnkp and horseflies have the highest flight speed - 14 - 15 m / s. Dragonflies fly at a speed of 10 m / s, dung beetles - up to 7 m / s, bees - up to 6 - 7 m / s. The flight speed of insects is slow compared to birds. However, if we calculate the relative speed (the speed at which a bumblebee, a swift, a starling and an airplane move over a distance equal to the length of its own body), then it turns out that it will be the least for an airplane and the most for insects.
Hans Leonardo da Vinci studied the flight of birds in search of ways to spin aircraft. II was interested in the flight of birds. V. Zhukovsky, who developed the fundamentals of aerodynamics. Now the principle of flapping flight again attracts the attention of self-builders
Jet propulsion in wildlife. Some animals move according to the principle of jet propulsion, for example, squids, octopuses (Fig. 8), cuttlefish. The marine mollusk-I rsbshok, sharply squeezing the shell valves, can move forward in jerks due to the reactive force of the water jet thrown into the shell. Approximately the same move and some other mollusks. Dragonfly larvae draw water into the hindgut, and then throw it out and jump forward due to the force of III “rush.
Since in these cases the shocks are separated from each other by significant intervals of time, a high speed of movement is not achieved. In order to increase the speed of movement, in other words, the number of reactive impulses per unit time, an increased conductivity of the nerves is necessary, which excite the contraction of the muscles serving the jet engine. Such a large conductivity is possible with a large diameter of the nerve. It is known that squids have the largest nerve fibers in the animal kingdom. They reach a diameter of 1 mm - 50 times larger than that of most mammals - and carry out excitation at a speed of 25 m/sec. This explains the high speed of squid movement (up to 70 km / h).
Accelerations and overloads that living beings are able to withstand. When studying Newton's laws, students can be introduced to the accelerations that a person faces in different life situations.
Accelerations in the elevator. The maximum acceleration (or deceleration) during the movement of the elevator car during normal operation should not exceed 2 m / s2 for all elevators. When stopping “stop”, the maximum acceleration value should not exceed 3 m/s2.
Acceleration in aviation. When a body experiences acceleration, it is said that it is subjected to an overload. The magnitude of overloads is characterized by the ratio of the acceleration of movement a to the acceleration of free fall g:
k = - . g
When skydiving, large accelerations and, consequently, overloads occur.
If you open a parachute at an altitude of 1000 m 15 seconds after the fall, then the overload will be about 6; opening the parachute after the same delay at 7000 m causes an overload equal to 12; at an altitude of 11,000 m under the same conditions, the overload will be almost three times greater than at an altitude of 1000 m.
When landing with a parachute, overloads also occur, which are the smaller, the longer the braking distance. Therefore, the g-force will be less when landing on soft ground. With a descent rate of 5 m/s and its repayment on the way of about 0.5 m due to bending of the knees and torso, the overload is approximately 3.5.
The maximum, though very short-term, accelerations are experienced by a person when ejecting from an airplane. At the same time, the seat departure speed from the cab is approximately 20 m/s, the acceleration path is -1 - 1.8 m. The maximum acceleration value reaches 180 - 190 m/s2, overload - 18 - 20.
However, despite the large value, such an overload is not hazardous to health, since it acts for a short time, approximately 0.1 sec.
Influence of accelerations on living organisms. Consider how accelerations affect the human body. Nerve impulses signaling the spatial movement of iivia, including the head, enter a special organ - the vestibular apparatus. The vestibular apparatus also informs the suture brain about the change in the speed of movement, therefore it is also called the organ of the acceleration sense. This piyarat is placed in the inner ear.
Characteristics of the threshold values ​​of irritations of the vestibular apparatus, reaching the consciousness of a person, as well as the acceleration retina during different movements, are shown in Table 3.

Accelerations directed from the back to the chest, from the chest to the back and from one side to the other are more easily tolerated. Therefore, the appropriate posture of a person is very important. A prerequisite is a general physical training, leading to a good development of the muscles of the whole body.
In addition, it is necessary to specifically train the body in order to increase endurance to accelerations. Such training is carried out on special linear accelerators, in centrifuges and on other installations.
Special anti-g suits are also used, the design of which ensures the fixation of internal organs.
It is interesting to recall here that K. E. Tsiolkovsky, in order to increase a person’s endurance to the action of accelerations, proposed placing his body in a liquid of the same density as it. It should be noted that such protection of the body from accelerations is quite widespread in nature. This is how the embryo is protected in the egg, this is how the fetus is protected in the womb. K. E. Tsiolkovsky placed a chicken egg in a jar of salt solution and dropped it from a height. The egg did not break.
At present, there are data on similar experiments with fish and frogs. The fish and frogs placed in the water withstood impact accelerations of the order of 1000 g and more.
Swordfish shock absorber. In nature, there are various adaptations that allow living organisms to painlessly endure the overloads that occur during acceleration and deceleration. It is known that the push during the jump softens if you land on half-bent legs; the role of a shock absorber is played by the spine, in which cartilage pads are a kind of buffers.
The swordfish has an interesting shock absorber. The swordfish is known as the record holder among sea swimmers. Its speed reaches 80 - 90 km / h. Her sword is capable of piercing the oak hull of a ship. She does not suffer from such a blow. It turns out that in her head at the base of the sword there is a hydraulic shock absorber - small honeycomb-shaped cavities filled with fat. They soften the blow. The cartilaginous pads between the vertebrae of the swordfish are very thick; like buffers on wagons, they reduce the force of the push.
Simple mechanisms in wildlife
In the skeleton of animals and humans, all bones that have some freedom of movement are levers, for example, in humans - the bones of the limbs, the lower jaw, the skull (the fulcrum is the first vertebra), the phalanges of the fingers. In cats, movable claws are levers; many fish have spines on the dorsal fin; in arthropods, most segments of their external skeleton; bivalve molluscs have shell valves.
Skeletal linkages are usually designed to gain speed with a loss in strength. Especially large gains in speed are obtained in insects.
The ratio of the length of the arms of the lever element of the skeleton is closely dependent on the vital functions performed by this organ. For example, the long legs of a greyhound and a deer determine their ability to run fast; the short paws of the mole are designed for the development of large forces at low speed; the long jaws of the greyhound allow you to quickly grab prey on the run, and the short jaws of the bulldog close slowly but strongly hold (the chewing muscle is attached very close to the fangs, and the strength of the muscles is transferred to the fangs almost without weakening).
Lever elements are found in different parts of the body of an animal and a person - these are, for example, limbs, jaws.
Let us consider the equilibrium conditions of the lever on the example of the skull (Fig. 9, a). Here the axis of rotation of the lever O passes through the articulation of the skull with the first vertebra. In front of the fulcrum on a relatively short shoulder, the force of gravity of the head acts, behind it is the force F of the traction of the muscles and ligaments attached to the occipital bone.
Another example of the operation of the lever is the action of the arch of the foot when lifting on the toes (Fig. 9, b). The support O of the lever, through which the axis of rotation passes, are the heads of the metatarsal bones. The overcome force R - the weight of the whole body - is applied to the talus. The acting muscle force F, which lifts the body, is transmitted through the Achilles tendon and applied to the protrusion of the calcaneus.
In plants, lever elements are less common, which is explained by the low mobility of the plant organism. A typical lever is a tree trunk and the main root that forms its continuation. The root of a pine or oak that goes deep into the ground has great resistance to tipping over (the shoulder of resistance is large), so pines and oaks almost never turn upside down. On the contrary, spruces, which have a purely superficial root system, tip over very easily.
Interesting linkage mechanisms can be found in some flowers (such as sage stamens) and also in some drop-down fruits.
Consider the structure of meadow sage (Fig. 10). The elongated stamen serves as the long arm A of the lever. At its end is an anther. The short arm B of the lever, as it were, guards the entrance to the flower. When an insect (most often a bumblebee) crawls into a flower, it presses on the short arm of the lever. At the same time, the long arm hits the back of the bumblebee with an anther and leaves pollen on it. Flying to another flower, the insect pollinates it with this pollen.
In nature, flexible organs are common that can change their curvature over a wide range (spine, tail, fingers, body of snakes and many fish). Their flexibility is due either to a combination of a large number of short levers with a linkage system,
or a combination of relatively inflexible elements with intermediate elements that are easily deformable (elephant trunk, caterpillar body, etc.). Bending control in the second case is achieved by a system of longitudinal or obliquely located rods.
The "piercing tools" of many animals - claws, horns, etc., are shaped like a wedge (a modified inclined plane); the pointed shape of the head of fast-moving fish is similar to a wedge. Many of these wedges are teeth, spines (Fig. 11) have very smooth hard surfaces (minimum friction), which is why they are very sharp.

Deformations
The human body experiences a rather large mechanical load from its own weight and from muscle efforts that occur during labor activity. Inter-
Resno that the example of a person can trace all types of deformation. Compression strains are experienced by the spinal column, lower extremities, and integument of the foot. Strain strains - upper limbs, ligaments, tendons, muscles; bending - spine, pelvic bones, limbs; torsion - neck when turning the head, torso in the lower back when turning, hands when rotating, etc.
To compile problems for deformations, we used the data given in Table 4.
The table shows that the modulus of elasticity for a bone or tendon in tension is very large, and for muscles, veins, arteries it is very small.
The ultimate stress that destroys the shoulder bone is about 8-107 N/m2, the ultimate stress that destroys the thigh bone is about 13-107 N/m2. Connective tissues in ligaments, in the lungs, etc., are highly elastic, for example, the occipital ligament can be stretched more than twice.
Structures made up of individual rods (trusses) or plates converging at an angle of 120° have maximum strength with minimal material consumption. An example of such structures are the hexagonal honeycomb cells.
Torsional resistance increases very rapidly with increasing thickness, so organs designed to perform torsional movements are usually long and thin (the neck of a bird, the body of a snake).
During deflection, the material is stretched along its convex side and compressed along its concave side; medium jaws of a noticeable de-
formations are not tested. Therefore, in technology, solid bars are replaced with pipes, beams are made T-beams or I-beams; this saves material and reduces the weight of the units. As you know, the bones of the limbs and stems of fast-growing plants - cereals (Fig. 12), umbrella plants, etc. have a tubular structure. In sunflower and other plants, the stem has a loose core. Young, immature leaves of cereals are always folded into a tube.
Structures similar to a T-beam are found in the sternum of birds, in the shells of many mollusks living in the surf zone, etc. The beam, arched upwards and having reliable supports that do not allow its ends to move apart (arch), has great strength in relation to efforts acting on its convex side (architectural arches, barrels; and in organisms - the skull, chest, shells of eggs, nuts, shells of beetles, crayfish, turtles, etc.).
The fall of living beings. Galileo Galilei wrote: “Who does not know that a horse, falling from a height of three or four cubits, breaks its legs, while the dog does not suffer, and the cat remains unharmed, being thrown from eight to ten cubits, just like a cricket , who fell from the top of the tower, or an ant that fell to the ground at least from the lunar sphere.
Why do small insects, falling to the ground from a great height, remain unharmed, while large animals die?
The strength of the bones and tissues of an animal is proportional to their cross-sectional area. The force of friction against air when bodies fall is also proportional to this area. The mass of an animal (and its weight) is proportional to its volume. As the size of the body decreases, its volume decreases much faster than the surface. Thus, with a decrease in the size of a falling animal, its deceleration force against the air (per unit mass) increases in comparison with the deceleration force per unit mass of a larger animal. On the other hand, for a smaller animal, bone strength and muscle strength increase (also per unit mass).
It is not entirely correct to compare the strength of a horse and a cat when they fall, since they have a different body structure, in particular, “shock-absorbing” devices that soften shocks during impacts are different. It would be more correct to compare a tiger, a lynx and a cat. The strongest among these felines would be a cat!
"Construction equipment" in the world of wildlife. After studying the topic "Solid Body" it is useful to talk about analogies in the "construction technique of nature" and the technique created by man.
The building art of nature and people develops according to the same principle - saving materials and energy.
Since ancient times, various designs of wildlife have been surprising and delighting. The strength and elegance of the spider's web is amazing, the building art of the honeybee dwelling delights - the strict geometry of their honeycombs, consisting of regular hexagonal cells. The structures of ants and termites are amazing. The coral islands and reefs formed by calcareous coral skeletons are amazing. Some seaweeds are covered with delicately shaped hard shells. For example, peridinia are dressed in bizarre shells formed by separate hard shells. They are shown at high magnification in Figure 13.
Even more diverse are marine radiolarians (the simplest animals), whose tiny skeletons are shown in Figure 14 (for comparison, snowflakes are shown under numbers - 3).
Recently, the attention of builders is occupied by samples of the plant world. K. A. Timiryazev wrote: “The role of the stem, katz is known, is mainly architectural: it is a solid skeleton of the entire building, carrying a tent of leaves, and in the thickness of which, like water pipes, vessels carrying juices are laid ... It was on the stems that we learned a whole series of amazing facts proving that they were built according to all the rules of building art.
If we consider the cross sections of the stem and the modern factory chimney, then the similarity of their designs is striking. The purpose of the pipe is to create draft and remove harmful gases away from the ground. Nutrients rise up the stem of the plant from the roots. Both the pipe and the stem are under the constant influence of the same type of static and dynamic loads - their own weight, wind, etc. These are the reasons for their structural similarity. Both designs are hollow. The stem strands, as well as the longitudinal reinforcement of the pipe, are located along the periphery of the entire circumference. There are oval voids along the walls of both structures. The role of spiral reinforcement in the stem is played by the skin.
It is known that the solid material in the bones is located in accordance with the trajectories of the main stresses. This can be found if we consider a longitudinal section of the upper part of the human femur and a curved crane beam working in bending under the action of a vertical load distributed over a certain area of ​​the upper surface. Interestingly, the steel Eiffel Tower resembles in its structure the tubular bones of a person (femur or tibia). There is a similarity in the external forms of structures, and in the corners between the “beams” and “beams” of the bone and the braces of the tower.
Modern architecture and building technology is characterized by attention to the best "examples" of wildlife. After all, modern requirements are strength and lightness, which can easily be satisfied by the use of steel, reinforced concrete, aluminum, reinforced cement, and plastics in construction. Spatial lattice systems are becoming widely used. Their prototypes are the "skeletons" of the stem or trunk of a tree, formed from a more durable tissue than the rest of the plant material, which performs biological and insulating functions. This is the system of veins of the leaf of the tree, and the lattice of root hairs. Such structures are reminiscent of baskets, the wire frame of a lampshade, a curved lattice of a balcony, etc. The Italian engineer P. Nervi used the principle of the structure of a tree leaf in the covering of the Turin exhibition hall, thanks to which the light and thin structure spans a 98-meter span without supports. The cover of our book depicts a building of this type, which looks like either a shell or an overturned cup of a flower.
Characteristic is the use of pneumatic structures, which are quite consistent with natural forms: the shape of fruits, air bubbles, blood vessels, plant leaves, etc.
In order to strengthen building materials, physical chemists have turned to the study of the smallest structures and are now developing a technology for the production of ultra-strong materials composed of many fine fibers, films and grains according to the principles suggested by nature. To obtain heavy-duty structures, however, it is not enough to strengthen building materials. It is known that bone structures sometimes surpass steel ones in a number of indicators, but this happens due to the “distribution” of bone material, which is inferior in strength to steel.
By creating this or that structure, nature solves many problems - it takes into account the necessary resistance to external mechanical influences and physical and chemical influences of the environment, provides plants with water, air, sun. All these
tasks are solved in a complex way, everything is subject to a common task, the general rhythm of the life of the organism. In plants you will not see freely suspended water capillaries, as in human structures. In addition to the task of uniform and constant movement of water, they also perform a mechanical function, resisting external mechanical influences of the environment.
And if you imagine the possibility of self-renewal of a constructive material during its operation, which is inherent in living nature! Apparently, protection from harmful chemical influences, from low and high temperatures can be found in the study of integumentary tissues of plants and animals.
The art of building, armed with bionics, will create a world of structures and buildings more natural and perfect than the one we are used to.

Power developed by man
When going through the topic “Work and Power”, it is interesting to provide some information about the power that a person is capable of developing.
It is believed that a person under normal working conditions can develop a power of about 70 - 80 watts (or approximately 0.1 hp). However, a short-term increase in power by several times is possible.
Thus, a person weighing 750 kilowatts can jump up to a height of 1 m in 1 second, which corresponds to a power of 750 watts. With a rapid ascent, for example, 7 steps, each of which is about 0.15 m high, a power of about 1 liter develops within 1 second. With. or 735 watts.
Recently, Olympic cyclist Brian Jolly tested 480 watts for 5 minutes, which is almost 2/3 hp. With.
An instantaneous, or explosive, release of energy is possible for a person, especially in sports such as shot put or high jump. Observations have shown that during high jumps with simultaneous repulsion with both legs, some men develop an average power of about 5.2 liters within 0.1 sec. s., and women - 3.5 a. With.

Devices for changing the lifting force
Interesting information about the structure of the body of sharks and sturgeons can be reported in connection with the study of the problem of the lifting force of an aircraft wing. It is known that when landing an aircraft, when its speed and, consequently, the lift force is small, additional devices are needed to increase the lift force. For this purpose, special shields are used -
flaps located on the lower surface of the wing, serving to increase the curvature of its profile. When landing, they bend down.
Bony fish (which include the vast majority of modern fish) regulate their average density and, accordingly, the depth of immersion with the help of a swim bladder. Cartilaginous fish have no such adaptation. Their lifting force is changed by changing the profile, like airplanes, for example, sharks (cartilaginous fish) change the lifting force with the help of pectoral and ventral fins.

Heart-lung machine (APC)
Finishing the study of mechanics, it is useful to tell students about the device of the heart-lung machine.
During operations on the heart, it often becomes necessary to temporarily turn it off from the circulation and operate on a dry heart.
Rice. fifteen.
The heart-lung machine consists of two main parts: a pump system and an oxygenator. Pumps perform the functions of the heart - they maintain pressure and blood circulation in the vessels of the body during surgery. The oxygenator performs the functions of the lungs and provides oxygen saturation to the blood.
A simplified diagram of the apparatus is shown in Figure 15. Piston pumps 18 are driven by an electric motor 20 through the regulator 19 \ the latter sets the rhythm and stroke of the pump pistons. The pressure through the tubes filled with oil is transmitted to pumps 4 and 9, which, using rubber diaphragms and valves, create the necessary vacuum in the venous part (pump 4) and compression in the arterial part (pump 9) of the physiological unit of the apparatus. The physiological block consists of a circulatory system, which, using polyethylene catheters, communicates with large vessels at the point of their exit from the heart and an oxygenator.
The blood is sucked through an air trap 1, an electromagnetic clamp 2, an equalization chamber 3, which performs the functions of the atrium, and is injected into the upper chamber 5 of the oxygenator using a pump 4. Here, the blood is evenly distributed over the column of blood foam that fills its middle chamber 6. It is a cylinder made of nylon mesh, at the bottom of which there is an oxygen distributor 7. Oxygen evenly through 30 holes enters the chamber through the air layer formed at the bottom of the chamber. The total surface of the bubbles in the foam column is approximately 5000 cm2 (with a blood volume of 150 - 250 cm3). In the oxygenator, the blood is saturated with oxygen, releases carbon dioxide into the surrounding atmosphere and flows into the lower chamber 8, from where it enters the arterial system of the body through a pump 9, a clamp 10 and an air trap 11. Oxygen enters the oxygenator through a gas meter 17 and a humidifier 16. In the upper part of the oxygenator there is a defoamer 12 and a gas outlet. A vessel 15 with spare blood or blood substitute fluid communicates with the oxygenator through the clamp 14. The flow of blood from the oxygenator is regulated by a float 13 connected inductively with a coil located outside, which controls the activation of the electromagnetic clamps of the device.

Questions and tasks

When solving problems related to living objects, great care must be taken to prevent misinterpretation of biological processes.
Consider the solution of several problems that we proposed to students.

Task 1. How to explain with the help of physical representations that in a storm a spruce tree easily breaks out along with the root, while a trunk breaks more quickly in a pine tree?
Before deciding, we read the characteristics of these trees.
“With its roots, spreading superficially, it (spruce. - Ts.K.) can tightly braid stones, which is why it has the necessary stability in the mountains, even with a very thin layer of soil, but since it does not, like a pine, vertically leaving down the root, then on the plains a separate spruce tree is easily pulled out by a storm along with the root. The crown of the tree forms a huge pyramid."
“The pine growing in the forest forms a tall columnar trunk and a small pyramidal crown. On the contrary, growing in a purely open place, it reaches only a small growth, but its crown grows widely.
Then they discussed with the students the possibility of applying the rule of moments to solve the problem.
We are interested in analyzing only the qualitative side of the issue. In addition, we are interested in the question of the comparative behavior of both trees. The role of the load in our problem is played by the wind force FB. It is possible to add the force of the wind acting on the trunk to the force of the wind acting on the crown, and even assume that the forces of the wind acting on both trees are the same. Then, apparently, further reasoning should "be as follows. The root system of a pine goes deeper into the ground than that of spruce. Due to this, the shoulder of the force holding the pine in the ground is greater than that of spruce (Fig. 16). Therefore, in order to It takes less wind torque to turn a spruce up by the root than it does to pine, and it takes more wind torque to uproot a pine than it does to break it.Therefore, spruce is uprooted more often than pine, and pine breaks more often than spruce.

KOHETS FRAGMEHTA BOOKS

Knowledge of human functions is one of the most difficult tasks. The development of science at the first stages occurs - the differentiation of disciplines aimed at a deep study of certain problems. At the first stage, we try to know a certain part, and when we succeed in doing this, another task arises - how to make a general idea. There are scientific disciplines at the junction of the original specialties. This also applies to biophysics, which appeared at the intersection of physiology, physics, physical chemistry and opened up new possibilities in understanding biological processes.

Biophysics- a science that studies physical and physico-chemical processes at different levels of living matter (molecular, cellular, organ, whole organism), as well as the laws and mechanisms of the impact of physical environmental factors on living matter.

Allocate-

• molecular biophysics - kinetics and thermodynamics of processes
• cell biophysics - study of cell structure and physico-chemical manifestations - permeability, formation of biopotentials
• biophysics of the sense organs - physical and chemical mechanisms of reception, energy transformation, information coding in receptors.
• Biophysics of complex systems - processes of regulation and self-regulation and thermodynamic features of these processes
• Biophysics of the impact of external factors - explores the impact on the body of ionizing radiation, ultrasound, vibration, exposure to light

Biophysics tasks

1. Establish patterns of wild nature by studying the physical and chemical phenomena in the body
2. The study of the mechanisms of the influence of physical factors on the body

Euler (1707-1783) - the laws of the theory of hydrodynamics, to explain the movement of blood through the vessels

Lavoisier (1780) - studied the exchange of energy in the body

Galvani (1786) - the founder of the doctrine of biopotentials, animal electricity

Helmholtz(1821)

X-ray - tried to explain the mechanisms of muscle contraction from the position of piezo effects

Arrhenius - laws of classical kinetics to explain biological processes

Lomonosov - the law of conservation and transformation of energy

Sechenov - studied the transport of gas in the blood

Lazarev - the founder of the national biophysical school

Pauling - the discovery of the spatial structure of the protein

Watson and Crick - discovery of the double structure of DNA

Hodgkin, Huxley, Katz - discovery of the ionic nature of bioelectrical phenomena

Prigogine - the theory of thermodynamics of irreversible processes

Eigen - the theory of hypercycles, as the basis of evolution

Sakman, Neher - established the molecular structure of ion channels

Biophysics became in connection with the development of medicine, because. methods of physical influence on the body were used there.

Biology was developing and it was necessary to penetrate the secrets of biological processes occurring at the molecular level

The need of industry, the development of which led to the action of various physical factors on the body - radioactive radiation, vibrations, weightlessness, overloads

Methods of biophysical research

• X-ray diffraction analysis- study of the atomic structure of matter, using X-ray diffraction. The distribution of the electron density of a substance is established from the diffraction pattern, and already from it it is possible to determine which atoms are contained in the substance and how they are located. Study of crystal structures, liquids and protein molecules.
• Column chromatography- different distribution and analysis of mixtures between 2 phases - mobile and stationary. It may be related to varying degrees of substance absorption or to varying degrees of ion exchange. Can be gas or liquid. The distribution of substances is used in capillaries - capillary, or in tubes filled with a sorbent - columnar. Can be done on paper, plates
• Spectral analysis- qualitative and quantitative determination of a substance by optical spectra. The substance is determined either by the emission spectrum - emission spectral analysis or by the absorption spectrum - absorption. The substance content is determined by the relative or absolute thickness of the lines in the spectrum. Also include radiospectroscopy - electron paramagnetic resonance and nuclear magnetic resonance.
• Isotope indication
• electron microscopy
• ultraviolet microscopy- the study of biological objects in UV rays increases the contrast of the image, especially intracellular structures, and it allows you to examine other cells without preliminary staining and fixing the preparation

One of the most important conditions for existence is adequate adaptation of functions, organs and tissues, systems to the environment. There is a constant balancing of the organism and the environment. In these processes, the main process is the regulation and control of physiological functions.

The general laws for the implementation, management and processing of information in different systems are studied by the science of cybernetics (cybernetics is the art of management). The laws of management are common to both humans and technical devices. The emergence of cybernetics was prepared by the development of the theory of automatic control, the development of radio electronics, and the creation of information theory.

This work was presented by Shannon (1948) in "The Mathematical Theory of Communication"

Cybernetics deals with the study of systems of any nature capable of receiving, storing and processing information and using it for management and regulation. Cybernetics studies those signals and factors that lead to certain control processes.

It is of great importance for medicine. The analysis of biological processes makes it possible to qualitatively and quantitatively study the mechanisms of regulation. Information processes of management and regulation are decisive in the body, i.e. are primary, on the basis of which all processes occur.

Systems- an organized complex of elements connected with each other and performing certain functions in accordance with the program of the entire system. The elements of the brain will be neurons. The elements of a team are the people who make it up. Only the crowd is not a cybernetic system.

Program- the sequence of changes in the system in space and time, which can be incorporated into the structure of the system or enter it from the outside.

Connection- the process of interaction of elements with each other, in which there is an exchange of matter, energy, information.

Messages are continuous and discrete.

Continuous have the character of a continuously changing value (blood pressure, temperature, muscle tension, musical melodies).

Discrete- consist of separate steps or gradations that differ from each other (portions of mediators, the nitrogenous base of DNA, dots and dashes of Morse code)

The process of coding information is also important. It is encoded by nerve impulses for the perception of information by the nerve centers. Code elements - symbols and positions. Symbols are dimensionless quantities that distinguish something (letters of the alphabet, mathematical signs, nerve impulses, molecules of odorous substances, and positions determine the spatial and temporal arrangement of symbols).

The information code contains the same information as the original message. This is the phenomenon of isomorphism. The code signal has a very low energy value. The arrival of information is evaluated by the presence or absence of a signal.

Message and information are not the same thing, because according to information theory

Information- a measure of the amount of uncertainty that is eliminated after receiving the message.

Possibility of an event a priori information.

The probability of an event after receiving the information is a posteriori information.

The informativeness of the message will be greater if the received information increases the posterior probability.

Information properties.

1. Information makes sense only if there are its receivers (consumer) - "if there is a TV in the room, and there is no one in it"
2. The presence of a signal does not necessarily indicate that information is being transmitted, because there are messages that do not carry anything new for the consumer.
3. Information can be transmitted both on the conscious and subconscious levels.
4. If the event is reliable (i.e. its probability is P=1), the message that it happened does not carry any information for the consumer
5. Message about an event, the probability of which is P< 1, содержит в себе информацию, и тем большую, чем меньше вероятность события, которого произошло.

Disinformation- negative value of information.

A measure of the uncertainty of events - entropy(H)

If log2 N=1 then N=2

Unit of information - bit(double unit of information)

H=lg N (hartley)

1 hartley is the amount of information needed to select one of ten equiprobable possibilities. 1 hartley = 3.3 bits

The regulator can work on compensation, when the effect on the body is a compensatory action of the regulator, which leads to the normalization of the function

Management is aimed at launching physiological functions, their correction and coordination of processes.

The most ancient is the humoral mechanism of regulation.

nervous mechanism.

neurohumoral mechanism.

The development of regulatory mechanisms leads to the fact that animals are able to move and can leave an unfavorable environment, unlike plants.

Outpost mechanism (in humans) - in the form of conditioned reflexes. On signaling stimuli, we can implement measures to influence the environment.

Biophysics (biological physics) - the science of the most simple and fundamental interactions underlying biological processes occurring at different levels of organization of living matter - molecular, cellular, organismal and population.

Introduction

Theoretical constructions and models of biophysics are based on the concepts of energy, force, types of interaction, on the general concepts of physical and formal kinetics, thermodynamics, and information theory. These concepts reflect the nature of the basic interactions and laws of motion of matter, which, as you know, is the subject of physics - a fundamental natural science. Biophysics as a biological science focuses on biological processes and phenomena. The main trend of modern biophysics is the penetration into the deepest, elementary levels that form the basis of the structural organization of the living.

The formation and development of biophysics is closely connected with the intensive interpenetration of ideas, theoretical approaches and methods of modern biology, physics, chemistry and mathematics.

Modern classification of biophysics adopted by IUPAB

The classification adopted by the International Union of Pure and Applied Biophysics (1961), which reflects the main biological objects in the field of biophysical research, includes the following sections: molecular biophysics, whose task is to study the physical and physico-chemical properties of macromolecules and molecular complexes; cell biophysics, which studies the physicochemical foundations of cell life, the relationship between the molecular structure of membranes and cell organelles and their functions, the patterns of coordination of cellular processes, their mechanical and electrical properties, energy and thermodynamics of cellular processes; biophysics of complex systems, which include individual organelles, whole organisms and populations; biophysics of control and regulation processes, which deals with the study and modeling of control principles in biological systems. There are also sections of biophysics: the structure of biopolymers (proteins, DNA, lipids), biomechanics, biological optics, biomagnetism, biological thermodynamics. Biophysics also includes areas of science that study the mechanisms of influence on biological systems of various physical factors (light, ionizing radiation, electromagnetic fields, etc.).

The history of the penetration of the principles of physics and mathematics into biology

The beginning of the study of the physical properties of biological objects is associated with the works of G. Galileo and R. Descartes (17th century), who laid the foundations of mechanics, on the principles of which the first attempts were made to explain some life processes. Descartes, for example, believed that the human body is like a complex machine, consisting of the same elements as inorganic bodies. The Italian physicist G. Borelli applied the principles of mechanics in describing the mechanisms of animal movements. In 1628, W. Harvey described the mechanism of blood circulation on the basis of the laws of hydraulics. In the 18th century discoveries in the field of physics and the improvement of its mathematical apparatus were of great importance for understanding the physicochemical processes occurring in living organisms. The use of physical approaches gave impetus to the introduction of experimental methods and ideas of the exact sciences into biology. L. Euler mathematically described the movement of blood through the vessels. M.V. Lomonosov made a number of general judgments about the nature of taste and visual sensations, put forward one of the first theories of color vision. A. Lavoisier and P. Laplace showed the unity of the laws of chemistry for inorganic and organic bodies, establishing that the process of respiration is similar to slow combustion and is a source of heat for living organisms. A creative discussion between A. Voltai and L. Galvani on the problem of the discovery by the latter of "living electricity" formed the basis of electrophysiology and played an important role in the study of electricity in general.

The development of biophysics in the 19th - early 20th century

In the 19th century the development of biology was accompanied by the enrichment of knowledge about the physicochemical properties of biological structures and processes. Of great importance was the creation of the electrolytic theory of solutions by S. Arrhenius, the ionic theory of bioelectric phenomena by V. Nernst. Basic ideas about the nature and role of action potentials in the mechanism of occurrence and propagation of excitation along the nerve were obtained ( G. Helmholtz, E. Dubois-Reymond, J. Bernstein, Germany); the importance of osmotic and electrical phenomena in the life of cells and tissues was elucidated thanks to the work of J. Loeb (USA), W. Nernst and R. Gerber (Germany). All this allowed Dubois-Reymond to conclude that no new forces are found in the material particles of organisms that could not act outside them. Such a principled position put an end to the explanations of life processes by the actions of some special "living factors that are not amenable to physical measurements."

Domestic scientists have made a significant contribution to the development of biophysics. THEM. Sechenov studied the patterns of dissolution of gases in the blood, the biomechanics of movements. The capacitor theory of excitation of nerve tissues, based on the unequal mobility of ions, was proposed by V.Yu. Chagovets. K.A. Timiryazev determined the photosynthetic activity of individual sections of the solar spectrum, establishing quantitative patterns that relate the rate of the photosynthesis process and the absorption of light by chlorophyll in leaves of different spectral composition. The ideas and methods of physics and physical chemistry were used in the study of movement, the organs of hearing and vision, photosynthesis, the mechanism of generation of electromotive force in the nerve and muscle, the importance of the ionic environment for the vital activity of cells and tissues. In 1905-15. N.K. Koltsov studied the role of physicochemical factors (surface tension, concentration of hydrogen ions, cations) in cell life. P.P. Lazarev is credited with the development of the ionic theory of excitation (1916) and the study of the kinetics of photochemical reactions. He created the first Soviet school of biophysicists, united around himself a large group of prominent scientists (they included S.I. Vavilov, S.V. Kravkov, V.V. Shuleikin, S.V. Deryagin, and others). In 1919, he founded the Institute of Biological Physics of the People's Commissariat of Health in Moscow, where work was carried out on the ion theory of excitation, the study of the kinetics of reactions occurring under the action of light, the absorption and fluorescence spectra of biological objects, as well as the processes of the primary impact on the body of various environmental factors. The books of V.I. Vernadsky (“Biosphere”, 1926), E.S. Bauer (“Theoretical Biology”, 1935), D.L. Rubinshtein (“Physico-chemical foundations of biology”, 1932), N.K. Koltsov (“Organization of the cell”, 1936), D.N. Nasonov and V.Ya. Alexandrova (“The reaction of living matter to external influences”, 1940), etc.

In the second half of the 20th century, advances in biophysics were directly related to advances in physics and chemistry, to the development and improvement of research methods and theoretical approaches, and the use of electronic computers. With the development of biophysics, such precise experimental methods of research as spectral, isotope, diffraction, and radiospectroscopic have penetrated into biology. The wide development of atomic energy stimulated interest in research in the field of radiobiology and radiation biophysics.

The main result of the initial period of the development of biophysics is the conclusion about the fundamental applicability in the field of biology of the basic laws of physics as a fundamental natural science about the laws of motion of matter. Of great general methodological significance for the development of various fields of biology are the proofs of the law of conservation of energy obtained during this period (the first law of thermodynamics), the approval of the principles of chemical kinetics as the basis for the dynamic behavior of biological systems, the concept of open systems and the second law of thermodynamics in biological systems, and finally, the conclusion about the absence any special "living" forms of energy. All this largely influenced the development of biology, along with the successes of biochemistry and advances in the study of the structure of biopolymers, contributed to the formation of the leading modern direction in biological science - physical and chemical biology, in which biophysics occupies an important place.

Main directions of research and achievements of modern biophysics

In modern biophysics, there are 2 main areas that make up the subject of biophysics - theoretical biophysics solves general problems of thermodynamics of biological systems, dynamic organization and regulation of biological processes, considers the physical nature of interactions that determine the structure, stability and intramolecular dynamic mobility of macromolecules and their complexes, the mechanisms of energy transformation in them; and biophysics of specific biological processes ( cell biophysics), the analysis of which is carried out on the basis of general theoretical concepts. The main trend in the development of biophysics is associated with penetration into the molecular mechanisms that underlie biological phenomena at different levels of organization of the living.

At the present stage of the development of biophysics, there have been fundamental shifts associated primarily with the rapid development of the theoretical sections of the biophysics of complex systems and molecular biophysics. It is in these areas, dealing with the regularities of the dynamic behavior of biological systems and the mechanisms of molecular interactions in biostructures, that general results have been obtained, on the basis of which biophysics has formed its own theoretical base. Theoretical models developed in such sections as kinetics, thermodynamics, the theory of regulation of biological systems, the structure of biopolymers and their electronic conformational properties form the basis in biophysics for the analysis of specific biological processes. The creation of such models is necessary to identify the general principles of fundamental biologically significant interactions at the molecular and cellular level, to reveal their nature in accordance with the laws of modern physics and chemistry using the latest advances in mathematics and to develop on the basis of this initial generalized concepts that are adequate to the described biological phenomena.

The most important feature is that the construction of models in biophysics requires such a modification of the ideas of related exact sciences, which is equivalent to the development of new concepts in these sciences as applied to the analysis of biological processes. Biological systems themselves are a source of information that stimulates the development of certain areas of physics, chemistry and mathematics.

In the field of biophysics of complex systems, the use of the principles of chemical kinetics for the analysis of metabolic processes has opened up wide possibilities for their mathematical modeling using ordinary differential equations. At this stage, many important results were obtained, mainly in the field of modeling physiological and biochemical processes, cell growth dynamics and populations in ecological systems. Of fundamental importance in the development of mathematical modeling of complex biological processes was the rejection of the idea of ​​obligatory finding of exact analytical solutions of the corresponding equations and the use of qualitative methods for the analysis of differential equations, which make it possible to reveal the general dynamic features of biological systems. These features include the properties of stationary states, their number, stability, the possibility of switching from one mode to another, the presence of self-oscillating modes, and the chaotization of dynamic modes.

On this basis, ideas were developed about the hierarchy of times and "minimal" and adequate models that quite fully reflect the main properties of the object. A parametric analysis of the dynamic behavior of systems was also developed, including the analysis of basic models that reflect various aspects of the self-organization of biological systems in time and space. In addition, the use of probabilistic models, which reflect the influence of stochastic factors on deterministic processes in biological systems, is becoming increasingly important. The bifurcation dependence of the dynamic behavior of the system on the critical values ​​of the parameters reflects the emergence of dynamic information in the system, which is realized when the operating mode changes.

The achievements of biophysics that are of general biological significance include the understanding of the thermodynamic properties of organisms and cells as open systems, the formulation, based on the 2nd law of thermodynamics, of the criteria for the evolution of an open system to a stable state ( I. Prigogine); disclosure of the mechanisms of oscillatory processes at the level of populations, enzymatic reactions. Based on the theory of autowave processes in active media, the conditions for the spontaneous appearance of dissipative structures in homogeneous open systems are established. On this basis, models of the processes of morphogenesis, the formation of regular structures during the growth of bacterial cultures, the propagation of a nerve impulse and nervous excitation in neural networks are built. A developing field of theoretical biophysics is the study of the origin and nature of biological information and its relationship with entropy, the conditions of chaos and the formation of fractal self-similar structures in complex biological systems.

In general, the development of a unified molecular-kinetic description is an urgent problem in biophysics, which requires the development of initial basic concepts. Thus, in the field of thermodynamics of irreversible processes, the concept of a chemical potential depending on the total concentration of any component, and, strictly speaking, the concept of entropy are no longer valid for heterogeneous systems that are far from equilibrium. In active macromolecular complexes, intramolecular transformations primarily depend on the nature of their organization, and not on the total concentration of individual constituent components. This requires the development of new criteria for the stability and direction of irreversible processes in heterogeneous nonequilibrium systems.

In molecular biophysics, the study of specific biological processes is based on data from studies of the physicochemical properties of biopolymers (proteins and nucleic acids), their structure, self-assembly mechanisms, intramolecular mobility, etc. Of great importance in biophysics is the use of modern experimental methods, primarily radio spectroscopy (NMR, EPR), spectrophotometry, X-ray diffraction analysis, electron tunneling microscopy, atomic force microscopy, laser spectroscopy, various electrometric methods, including using microelectrode technology. They make it possible to obtain information about the mechanisms of molecular transformations without violating the integrity of biological objects. At present, the structure of about 1000 proteins has been established. Deciphering the spatial structure of enzymes and their active center makes it possible to understand the nature of the molecular mechanisms of enzymatic catalysis and plan the creation of new drugs on this basis. The possibilities of targeted synthesis of biologically active substances, including drugs, are also based on fundamental studies of the relationship between molecular mobility and biological activity of such molecules.

In the field of theoretical molecular biophysics, ideas about electronic-conformational interactions - EKV(M.V. Wolkenstein), stochastic properties of the protein ( ABOUT. Ptitsyn) form the basis for understanding the principles of functioning of biomacromolecules. The specificity of biological patterns, which are fully revealed at the highest levels of organization of a developed biological system, nevertheless, manifests itself already at the lower molecular levels of the living. Energy transformation and the appearance of reaction products in complexes is achieved as a result of intramolecular interactions of individual parts of the macromolecule. From this, ideas about the uniqueness of a macromolecule as a physical object that combines interactions in statistical and mechanical degrees of freedom follow logically. It is the ideas about macromolecules, primarily protein ones, as a kind of molecular machines ( L.A. Blumenfeld, D.S. Chernavsky) make it possible to explain the transformation of various types of energy as a result of interaction within a single macromolecule. The fruitfulness of the biophysical method of analysis and construction of generalized models of physical interaction is reflected in the fact that the EQI principle allows us to consider the functioning of molecular machines, seemingly far from each other in their biological role, from a unified general scientific position - for example, molecular complexes involved in the primary processes of photosynthesis and vision, enzyme-substrate complexes of enzymatic reactions, molecular mechanisms of the ATP synthetase, as well as the transfer of ions through biological membranes.

Biophysics studies properties biological membranes, their molecular organization, conformational mobility of protein and lipid components, their resistance to temperature, lipid peroxidation, their permeability to non-electrolytes and various ions, molecular structure and mechanisms of functioning of ion channels, intercellular interactions. Much attention is paid to the mechanisms of energy conversion in biostructures (see Art. Bioenergetics), where they are associated with the transfer of electrons and with the transformation of the energy of electronic excitation. The role of free radicals in living systems and their significance in the damaging effect of ionizing radiation, as well as in the development of a number of other pathological processes ( N.M. Emanuel, B.N. Tarusov). One of the branches of biophysics bordering on biochemistry is mechanochemistry, which studies the mechanisms of interconversions of chemical and mechanical energy associated with muscle contraction, movement of cilia and flagella, movement of organelles and protoplasm in cells. An important place is occupied by "quantum" biophysics, which studies the primary processes of interaction of biological structures with light quanta (photosynthesis, vision, effects on the skin, etc.), the mechanisms of bioluminescence and phototropic reactions, the action of ultraviolet and visible light ( photodynamic effects) on biological objects. Back in the 40s. 20 in . A.N. Terenin revealed the role of triplet states in photochemical and a number of photobiological processes. A.A. Krasnovsky showed the ability of chlorophyll excited by light to undergo redox transformations, which underlie the primary processes of photosynthesis. Modern methods of laser spectroscopy provide direct information about the kinetics of the corresponding photoinduced electronic transitions, vibrations of atomic groups in the range from 50-100 femtoseconds to 10 -12 -10 -6 s and more.

The ideas and methods of biophysics are not only widely used in the study of biological processes at the macromolecular and cellular levels, but also spread, especially in recent years, to the population and ecosystem levels of organization of living nature.

Advances in biophysics are largely used in medicine and ecology. Medical biophysics deals with the identification in the body (cell) at the molecular level of the initial stages of pathological changes. Early diagnosis of diseases is based on the registration of spectral changes, luminescence, electrical conductivity of blood and tissue samples accompanying the disease (for example, the level of chemiluminescence can be used to judge the nature of lipid peroxidation). analyzes the molecular mechanisms of action of abiotic factors (temperature, light, electromagnetic fields, anthropogenic pollution, etc.) on biological structures, viability and stability of organisms. The most important task of ecological biophysics is the development of express methods for assessing the state of ecosystems. In this area, one of the most important tasks is to assess the toxicity of fundamentally new materials - nanomaterials, as well as the mechanisms of their interaction with biological systems.

In Russia, research in biophysics is carried out in a number of research institutes and universities. One of the leading places belongs to the scientific center in Pushchino, where in 1962 the Institute of Biological Physics of the USSR Academy of Sciences was organized, which later was divided into Institute of Cell Biophysics RAS(Director - Corresponding Member of the Russian Academy of Sciences E.E. Fesenko) and Institute for Theoretical and Experimental Biophysics RAS(Director - Corresponding Member of RAS G.R. Ivanitsky. Biophysics is actively developing in Institute of Biophysics of the Ministry of Health of the Russian Federation, Institute of Molecular Biology RAS and Institute of Protein RAS, Institute of Biophysics SB RAS(Director - Corresponding Member of the Russian Academy of Sciences Degermedzhi A.G.), at the universities of Moscow. St. Petersburg and Voronezh, in, in, etc.

Development of biophysical education in Russia

In parallel with the development of research, the formation of a base for training specialists in the field of biophysics was going on. The first in the USSR Department of Biophysics at the Faculty of Biology and Soil Science of Moscow State University was organized in 1953 (B.N. Tarusov), and in 1959 the Department of Biophysics was opened at the Faculty of Physics of Moscow State University (L.A. Blumenfeld). Both of these departments are not only educational centers that train qualified biophysicists, but also major research centers. The departments of biophysics were then organized in a number of other universities in the country, including State University "Moscow Institute of Physics and Technology", in National Research Nuclear University "MEPhI" as well as at leading medical universities. The course of biophysics is taught in all universities of the country. Biophysical research is carried out at institutes and universities in many countries of the world. International congresses on biophysics are held regularly every 3 years. Societies of biophysicists exist in the USA, Great Britain and a number of other countries. In Russia, the Scientific Council for Biophysics at the Russian Academy of Sciences coordinates scientific work and carries out international relations. The biophysics section is available at Moscow Society of Naturalists.

Among the periodicals in which articles on biophysics are published are: "Biophysics" (M., 1956 -); "Molecular Biology" (M., 1967 -); "Radiobiology" (M., 1961 - currently "Radiation biology. Radioecology"); "Biological membranes" (M., 19 -). "Advances in Biological and Medical Physics" (N.Y., 1948 -); "Biochimica et Biophysica Acta" (N.Y. - Amst., 1947 -); "Biophysical Journal" (N.Y., I960 -); "Bulletin of Mathematical Biophysics" (Chi, 1939 -); "Journal of Cell Biology" (N.Y., 1962 -. In 1955 - 1961 "Journal of Biophysical and Biochemical Cytology"); "Journal of Molecular Biology" (N.Y. - L., 1959 -); "Journal of Ultrastructure Research" (N.Y. - L., 1957 -) "Progress in Biophysics and Biophysical Chemistry" (L., 1950 -) ; European Journal of biophysics (); Jurnal of Theoretical Biology (1961).

Recommended reading

Blumenfeld L.A. Problems of biological physics. M., 1977

Volkenstein M.V. Biophysics. M., 1981

M. Jackson. Molecular and cellular biophysics. M., Mir. 2009

Nicolis G., Prigogine I. Self-organization in non-equilibrium structures. per. from English. M., 1979;

Rubin A.B. Biophysics. T. I. M., 2004. T. 2. M., 2004 (3rd edition)

A.V., Ptitsyn O.B. Protein physics. M., 2002.

FEDERAL AGENCY FOR EDUCATION

STATE EDUCATIONAL INSTITUTION

HIGHER VOCATIONAL EDUCATION

"IRKUTSK STATE PEDAGOGICAL UNIVERSITY"

Department of Physics

Faculty of Mathematics, Physics and

informatics

specialty "540200 - physical

mathematical education"

physics profile

Qualification Bachelor of Physical and Mathematical Education

Correspondence form of education

COURSE WORK

Biophysics at physics lessons in grades 7-9

Completed by: Rudykh Tatyana Valerievna

Scientific adviser: candidate

in Physics and Mathematics Lyubushkina Lyudmila Mikhailovna

Date of protection ______________________

Mark _________________________

Irkutsk 2009

Introduction 3

CHAPTERI . FORMATION OF BIOPHYSICS

1.1. The contribution of scientists to the development of biophysics 5

1.2. Founder of Biophysics 10

1.3. Creation of quantum theory 11

1.4. Applied Biophysics 14

1.5. Changes in biophysics 16

1.6. Biophysics as theoretical biology 18

1.7. Biophysical research in physics 21

1.8. Biophysical research in biology 23

CHAPTERII. BIOPHYSICS IN PHYSICS LESSONS

2.1. Elements of biophysics in physics lessons in grades 7-9 24

2.2. Application of biophysics in the lessons at the basic school 25

2.3. Blitz Tournament "Physics in Wildlife" 33

Conclusion 35

References 36

Introduction

The relevance of research:

Worldview is the most important component of personality structure. It includes a system of generalized views about the world, about a person's place in it, as well as a system of views, beliefs, ideals, principles that correspond to a certain worldview. The process of formation of the worldview takes place intensively at school age. Already in the basic school (grades 7-9), students should realize that the study of physical phenomena and laws will help them in understanding the world around them.

However, most of the new physics textbooks, especially for senior basic and specialized schools, do not contribute to a holistic perception of the material being studied. Children's interest in the subject is gradually fading away. Therefore, an important task of the secondary school is to create in the minds of students a general picture of the world with its unity and diversity of properties of inanimate and living nature. The integrity of the picture of the world is achieved along with other techniques and interdisciplinary connections.

Any topic of a school physics course includes elements of scientific knowledge that are essential for the formation of a worldview and for the assimilation by schoolchildren of the fundamental concepts of the discipline being studied. Since the content of natural science disciplines is not rigidly structured in educational standards and programs, often the knowledge of schoolchildren is not systematized, formal.

Research problem consists in the need to form a holistic perception of the physical picture of the world and the lack of appropriate systematization and generalization of the educational material of the taught discipline, physics.

Purpose of the study: To trace the integration of two subjects of the natural science cycle - physics and biology.

Object of study: Biophysics and its relationship with other subjects.

Subject of study: Biophysics at physics lessons in grades 7-9main school.

Realization of the set goal required the solution of a number of specific tasks:

To study and analyze educational and methodical literature on the research topic.

Analyze various biophysical phenomena.

Select experimental tasks, various types of tasks, the solution of which requires knowledge of both physics and biology.

Practical significance of the study: the results of the work can be recommended for practical use teachers in teaching physics in all educational institutions.

The logic of the study determined the structure of the work, consisting of an introduction, two chapters, a conclusion, a list of references. The first chapter is devoted to the analysis of educational literature on the topic "Biophysics and its relationship with other subjects", the second chapter examines the relationship between physics and biology on the example of specific tasks.

In conclusion, the results of the study are summarized and recommendations are given for improving the application of biophysical phenomena in the study of the school course in physics.

Chapter I. FORMATION OF BIOPHYSICS

1.1. The contribution of scientists to the development of biophysics.

Biophysics- a branch of natural science dealing with the physical and physico-chemical principles of the organization and functioning of biological systems at all levels (from submolecular to biospheric), including their mathematical description. Biophysics fundamentally deals with the mechanisms and properties of living systems. Living is an open system capable of self-maintenance and self-reproduction.

As a multidisciplinary science, biophysics was formed in the 20th century, but its prehistory goes back more than one century. Like the sciences that led to its emergence (physics, biology, medicine, chemistry, mathematics), biophysics underwent a series of revolutionary transformations by the middle of the last century. It is known that physics, biology, chemistry and medicine are closely related sciences, but we are used to the fact that they are studied separately and independently. Essentially, an independent separate study of these sciences is wrong. A natural scientist can ask inanimate nature only two questions: "What?" And How?". "What" is the subject of research, "how" - how this subject is arranged. Biological evolution has brought wildlife to a unique expediency. Therefore, a biologist, a physician, a humanist can also ask a third question: “Why?” or “For what?”. Ask "Why the Moon?" maybe a poet, but not a scientist.

Scientists knew how to ask Nature the right questions. They made an invaluable contribution to the development of physics, biology, chemistry and medicine - the sciences that, together with mathematics, formed biophysics.

From the time of Aristotle (384 - 322 BC) physics included the totality of information about inanimate and living nature (from the Greek. "Physis" - "Nature"). Steps of nature in his view: the inorganic world, plants, animals, man. The primary qualities of matter are two pairs of opposites "warm - cold", "dry - wet". The fundamental elements of the elements are earth, air, water, fire. The highest, most perfect element is ether. The elements themselves are various combinations of primary qualities: the combination of cold and dry corresponds to earth, cold to wet - water, warm to wet - air, warm to dry - fire. The concept of ether subsequently served as the basis for many physical and biological theories. In modern terms, Aristotle's ideas are based on the non-additivity of the addition of natural factors (synergism) and the hierarchy of natural systems.

As an exact natural science, as a science in the modern concept, physics originates from Galileo Galilei (1564 - 1642), who initially studied medicine at the University of Pisa and only then became interested in geometry, mechanics and astronomy, writings Archimedes (c. 287 - 212 BC) and Euclid (3rd century BC).

Universities provide a unique opportunity to experience the temporal connection of sciences, in particular, physics, medicine and biology. So in the 16-18 centuries, the direction of medicine, which was called "iatrophysics" or "iatromechanics" (from the Greek "iatros" - "doctor"). Doctors tried to explain all the phenomena in a healthy and diseased human and animal body on the basis of the laws of physics or chemistry. And then, and in subsequent times, the connection between physics and medicine, physicists and biologists was the closest, after iatrophysics, iatrochemistry appeared. The division of the science of "living and non-living" occurred relatively recently. The participation of physics with its powerful and deeply developed theoretical, experimental and methodological approaches in solving the fundamental problems of biology and medicine is undeniable, however, it should be recognized that in the historical aspect of physics it is in great debt to physicians, who were the most educated people of their time, and whose contribution to the creation of fundamental the foundations of classical physics is invaluable. Of course, we are talking about classical physics.

Among the oldest subjects of biophysical research, however strange it may seem at first glance, bioluminescence should be mentioned, since the emission of light by living organisms has long been of interest to natural philosophers. For the first time, Aristotle drew attention to this effect with his pupil Alexander the Great, to whom he showed the glow of the littoral and saw the reason for this in the luminescence of marine organisms. The first scientific study of the "animal" glow was made by Athanasis Kircher (1601 - 1680), German priest, encyclopedist, known as a geographer, astronomer, mathematician, linguist, musician and physician, creator of the first natural science collections and museums, two chapters of his book "The Art of the Great Light and Shadow" ("Ars magna Lucis et Umbrae ») he dedicated to bioluminescence.

By the nature of his scientific interests, the greatest physicist can be attributed to biophysicists Isaac Newton (1643 - 1727), who was interested in the problems of the connection between physical and physiological processes in organisms and, in particular, dealt with issues of color vision. Completing his Principia, in 1687 Newton wrote: “Now one should add something about some very thin ether that penetrates all solid bodies and is contained in them, by whose force and actions the particles of bodies at very small distances are mutually attracted, and when they come into contact cohesive, electrified bodies act over long distances, both repelling and attracting close bodies, light is emitted, reflected, refracted, deflected and heats the bodies, every feeling is excited, forcing the limbs of animals to move at will, being transmitted by vibrations of this ether from external sense organs to the brain and from the brain to the muscles.

One of the founders of modern chemistry French Antoine Laurent Lavoisier (1743 - 1794) together with his compatriot astronomer, mathematician and physicist Pierre Simon Laplace (1749 - 1827) engaged in calorimetry, a branch of biophysics that would now be called biophysical thermodynamics. Lavoisier applied quantitative methods, dealing with thermochemistry, oxidation processes. Lavoisier and Laplace substantiated their ideas that there are no two chemistry - "living" and "non-living", for inorganic and organic bodies.

Among our great predecessors, who laid the foundations of biophysics, should be attributed the Italian anatomist Luigi Galvani(1737 - 1798) and physics Alessandro Volta(1745 - 1827), creators of the doctrine of electricity. Galvani was experimenting with an electric machine and one of his friends accidentally touched a frog's thigh with a knife, which was going to be used in soup. When the frog's leg muscles suddenly contracted, Galvani's wife noticed that the electric machine flashed and wondered "whether there was any connection between these events." Although Galvani's own opinion about this phenomenon differed in detail from the following, it is certain that the experiment was repeated and verified. , who stated that the leg served only as a detector of differences in the electrical potential external to it. Galvani's supporters conducted an experiment in which no external electrical forces were involved, thus proving that the current generated by the animal could cause muscle contraction. But it was also possible that the contraction was caused by contact with metals; Volta made the corresponding researches, and they led to his discovery of the electric battery, which was so important that Galvani's researches stepped aside. As a result, the study of electrical potential in animals disappeared from scientific attention until 1827. Since for many years the frog's leg was the most sensitive detector of differences in potential, the final understanding that currents could be generated by living tissues did not come until galvanometers sensitive enough to measure currents generated in the muscles and small differences in potential across the nerve membrane.

In connection with the works of Galvani on "animal electricity" one cannot but recall the name of an Austrian physician - physiologist Friedrich Anton Mesmer(1733-1815), who developed ideas about the healing "animal magnetism", through which, according to his assumption, it was possible to change the state of the body, treat diseases. It should be noted that even now the effects of the action of electric magnetic and electromagnetic fields on living systems remain largely a mystery to fundamental science. Problems remain and, indeed, the interest of modern physicists in studying the influence of external physical factors on biological systems does not fade away.

However, before biology and physics had time to separate, the well-known book "Grammar of Science" was published, written by an English mathematician Karl Pearson (1857 - 1935) in which he gave one of the first definitions of biophysics (in 1892): “We cannot say with complete certainty that life is a mechanism until we are able to specify more precisely what exactly we mean by the term “mechanism” as applied to organic bodies. Already now it seems certain that some generalizations of physics ... describe ... part of our sensory experience regarding life forms. We need ... a branch of science that has as its task the application of the laws of inorganic phenomena, physics to the development of organic forms. ... The facts of biology - morphology, embryology and physiology - form special cases of the application of general physical laws. ... It would be better to call it biophysics.”

1.2. Founder of Biophysics

The founder of modern biophysics should be consideredHermann L. Ferdinand von Helmholtz (1821-1894), who became an outstanding physicist, one of the authors I the law of thermodynamics. While still a young military surgeon, he showed that metabolic transformations in muscles are strictly related to the mechanical work they perform and heat generation. In his mature years, he dealt a lot with problems of electrodynamics. In 1858 he laid the foundations for the theory of the vortex motion of a liquid. He also performed brilliant experiments in the field of biophysics of the nerve impulse, biophysics of vision, bioacoustics, developed Jung's idea of ​​three types of visual receptors, electrical discharges arising in an electrical circuit have an oscillatory character. Interest in oscillatory processes in acoustics, liquids, electromagnetic systems led the scientist to study the wave process of nerve impulse propagation. It was Helmholtz who first began studying the problems of active media, measuring with high accuracy the speed of propagation of a nerve impulse in axons, which, from the modern point of view, are an active one-dimensional medium. In 1868 Helmholtz was elected an honorary member of the St. Petersburg Academy of Sciences.

The fates of the Russian scientist, physiologist and biophysicist are connected in an amazing way, Ivan Mikhailovich Sechenov(1829 - 1905) and Helmholtz. After graduating from Moscow University in 1856 until 1860, he studied and worked with Helmholtz. From 1871 to 1876, Sechenov worked at the Novorossiysk University in Odessa, then at St. Petersburg and Moscow Universities, studying electrical phenomena in nerve tissues, and the mechanisms of gas transport in the blood.

1.3. Creation of quantum theory

However, the period of classical physics of the 17th-19th centuries ended at the beginning of the 20th century with the greatest revolution in physics - the creation of quantum theory. This and a number of other new areas of physics distinguished it from the circle of natural sciences. At this stage, the interaction between physics and medicine changed its character significantly: practically all modern methods of medical diagnostics, therapy, pharmacology, etc. began to be based on physical approaches and methods. This does not diminish the outstanding role of biochemistry in the development of medicine. . Therefore, we should talk about those outstanding scientists whose names are associated with the unification of sciences and the formation of biophysics. We are talking about physicists who entered the history of biology and medicine, about doctors who made a significant contribution to physics, although it would seem difficult for physicists to enter into the specific problems of medicine, deeply permeated with ideas, knowledge and approaches of chemistry, biochemistry, molecular biology and etc. At the same time, doctors also encounter fundamental difficulties in trying to formulate their needs and tasks that could be resolved by appropriate physical and physicochemical methods. There is only one effective way out of the situation, and it has been found. This is a universal university education, when students, future scientists, can and should receive two, three and even four fundamental educations - in physics, chemistry, medicine, mathematics and biology.

Niels Bohr argued that "no result of biological research can be unambiguously described otherwise than on the basis of the concepts of physics and chemistry." This meant that biology, medicine, mathematics, chemistry and physics again, after almost a century and a half of separation, began to converge, resulting in the emergence of such new integral sciences as biochemistry, physical chemistry, and biophysics.

British physiologist and biophysicist Archibald Vivienne Hill (b. 1886), Nobel laureate in physiology (1922) is the creator of the fundamental foundations on which the theory of muscle contractions is still developing today, but already at the molecular level. Hill described biophysics in this way: “There are people who can formulate a problem in physical terms ... who can express the result in terms of physics. These intellectual qualities more than any special conditions, physical apparatus and methods are necessary, to become a biophysicist ... However ... a physicist who cannot develop a biological approach, who is not interested in living processes and functions ... who considers biology only a branch of physics, has no future in biophysics.

Not only in the Middle Ages, but also in recent times, physicians, biologists and physicists participated on an equal footing in the development of the complex of these sciences. Alexander Leonidovich Chizhevsky (1897-1964), who received, among others, a medical education at Moscow University, for many years he was engaged in research on heliochronobiology, the effect of air ions on living organisms, and the biophysics of erythrocytes. His book "Physical Factors of the Historical Process" was never published despite the efforts of P.P. Lazarev, N.K. Koltsov, People's Commissar of Education Lunacharsky and others.

It should also be noted the outstanding scientist Gleb Mikhailovich Frank(1904-1976), who created the Institute of Biophysics of the Academy of Sciences of the USSR (1957), received the Nobel Prize together with I.E. Tamm and P.A. Cherenkov for the creation of the theory of "Cherenkov radiation". The oscillatory behavior of biological systems of all levels, known from time immemorial, has occupied not only biologists, but also physical chemists and physicists. The discovery in the 19th century of fluctuations in the course of chemical reactions subsequently led to the emergence of the first analog models, such as the "iron nerve", "mercury heart".

Thermodynamic line development of biophysics was naturally associated with the evolution of thermodynamics itself. Moreover, the non-equilibrium nature of open biological systems, intuitively accepted by naturalists, contributed to the formation of the thermodynamics of non-equilibrium systems. The thermodynamics of equilibrium systems, originally associated mainly with calorimetry, subsequently made a significant contribution to the description of structural changes in cells, metabolism, and enzymatic catalysis.

The list of outstanding medical physicists could be significantly expanded, but the goal is to reveal the deep connections between biology, chemistry, medicine and physics, the impossibility of a differentiated existence of these sciences. Much of the biophysical research has been done by physicists interested in biology; therefore, there must be a way for scientists trained in physics and physical chemistry to find their way into biology and become familiar with problems open to physical interpretation. Although classically oriented biology departments often offer posts to biophysicists, they are not a substitute for centers where biophysical research is central.

Biophysicists have the ability to divide biological problems into segments that lend themselves to direct physical interpretation, and to formulate hypotheses that can be tested experimentally. The main tool of biophysics is the relation. Added to this is the ability to use complex physical theory to study living things, for example: X-ray diffraction technology was needed to establish the structure of large molecules such as proteins. Biophysicists generally recognize the use of new physical tools, such as atomic magnetic resonance and electron spin resonance, in the study of certain problems in biology.

1.4. Applied Biophysics

The development of tools for biological purposes is an important aspect of the new field of applied biophysics. Biomedical instruments are probably most widely used in medical settings. Applied biophysics is important in the field of therapeutic radiology, in which dose measurement is very important for treatment, and diagnostic radiology, especially with technologies that involve isotope localization and whole body scanning, to help with the diagnosis of tumors. The importance of computers in determining the diagnosis and treatment of the patient is growing. The possibilities for applications of applied biophysics seem endless, as the long delay between the development of research tools and their application means that many scientific tools based on physical principles already known will soon become essential to medicine.

Russian biophysics as a branch of science was largely formed among outstanding Russian scientists of the end of the past, the beginning of this century - physicists, biologists, physicians, closely associated with Moscow University. Among them were N.K.Koltsov, V.I.Vernadsky, P.N. Lebedev, P.P. Lazarev, later - S.I. Vavilov, A.L. Chizhevsky and many others.

James D. Watson(1928) together with the English biophysicist and geneticist Francis H.K. cry(1916) and biophysicist Maurice Wilkins(1916) (who first obtained high-quality X-rays of DNA together with Rosalind Franklin) created a three-dimensional model of DNA in 1953, which made it possible to explain its biological functions and physico-chemical properties. In 1962, Watson, Crick and Wilkins received the Nobel Prize for this work.

The first lecture course in Russia called "Biophysics" was read for doctors at the clinic of Moscow University in 1922 Petr Petrovich Lazarev(1878 - 1942), elected in 1917 on the nomination Ivan Petrovich Pavlov(1849 - 1936) academician. P.P. Lazarev graduated from the medical faculty of Moscow University in 1901. He then completed a full course in physics and mathematics and worked in a physics laboratory run by Petr Nikolaevich Lebedev(1866-1912), one of the founders of experimental physics in Russia, the creator of the first Russian scientific physical school, who in 1985 received and studied millimeter electromagnetic waves, discovered and measured light pressure on solids and gases (1999-1907), which confirmed the electromagnetic theory of light. In 1912, Lazarev headed the laboratory of his teacher. The first biophysicist, Academician Lazarev, headed the unique Institute of Physics and Biophysics, created during Lebedev's lifetime. From 1920 to 1931, P.P. Lazarev headed this State Institute of Biophysics, created on his initiative, Lazarev is the founder of medical radiology, his institute had the first and only X-ray unit on which Lenin was photographed after the assassination attempt in 1918, after which Lazarev became the initiator and first director of the Institute of Medical Radiology. Lazarev also organized work on magnetic mapping of the Kursk magnetic anomaly, thanks to which the staff of the Institute of Physics of the Earth was formed. However, the Institute of Biophysics and Physics was destroyed after the arrest of Lazarev in 1931, and in 1934 the Lebedev FIAN was founded in this building.

1.5. Changes in biophysics

Since the 1940s, dramatic changes have begun in biophysics. And that was the call of the times - by the middle of our century, physics, which had made a phenomenal leap, was actively entering biology. However, by the end of the 1950s, the euphoria from the expectation of a quick solution to complex problems of the living quickly passed: it was difficult for physicists without fundamental biological and chemical education to single out accessible to physics, but “biologically significant” aspects of the functioning of living systems, and real biologists and biochemists about the existence of specific physical problems and approaches, as a rule, were not suspected. An urgent need for the science of those and subsequent days was the training of specialists with three fundamental formations: physical, biological and chemical.

In our country there was another important reason for the emergence in the 1940s of a close alliance between biology and physics. After the unprofessional, destructive intervention of politicians of that time in the fundamental areas of genetics, molecular biology, the theory and practice of nature management, some of the biologists were able to continue their research only in scientific institutions of the physical profile.

Like any borderline area of ​​knowledge, based on the fundamental sciences of physics, biology, chemistry, mathematics, on the achievements of medicine, geophysics and geochemistry, astronomy and space physics, etc. Biophysics initially requires an integrated, encyclopedic approach to itself from its carriers, since it is aimed at elucidating the mechanisms of the functioning of living systems at all levels of the organization of living matter. Moreover, this also determines the frequent misunderstanding in relation to biophysics and biophysicists on the part of colleagues, representatives of related disciplines. It is difficult, sometimes almost impossible, to distinguish between biophysics and physiology, biophysics and cell biology, biophysics and biochemistry, biophysics and ecology, biophysics and chronobiology, biophysics and mathematical modeling of biological processes, etc. Thus, biophysics is aimed at elucidating the mechanisms of functioning of biological systems at all levels and on the basis of all natural science approaches.

1.6. Biophysics - as theoretical biology

It is known that biologists, chemists, physicians, engineers, and the military are also involved in biophysics, but the system for training biophysicists turned out to be optimal on the basis of a general university education in physics. At the same time, biophysics has been and is being treated as theoretical biology, i.e. the science of the fundamental physical and physico-chemical foundations of the structure and functioning of living systems at all levels of organization - from the submolecular level to the level of the biosphere. The subject of biophysics is living systems, the method is physics, physical chemistry, biochemistry and mathematics.

In the 50s of the 20th century, students of the Faculty of Physics, following their teachers, also showed interest in the problems of medicine and biology. Moreover, it seemed possible to give a rigorous physical analysis of the most remarkable phenomenon in the Universe - the phenomenon of Life. The book translated in 1947 E. Schrödinger“What is life? From a physics point of view. Cytological aspect of the living”, lectures I.E.Tamma, N.V. Timofeev-Resovsky, the latest discoveries in biochemistry and biophysics prompted a group of students to apply to the rector of Moscow State University I.G. Petrovsky with a request to introduce the teaching of biophysics at the Faculty of Physics. The rector paid great attention to the initiative of the students. Lectures and seminars were organized, which were enthusiastically attended not only by the initiators, but also by classmates who joined them, who later formed the first specialization group "Biophysics" of the Faculty of Physics of Moscow State University and are now the pride of Russian biophysics.

The Department of Biophysics of the Biological Faculty was founded in 1953. Its first head was B.N. Tarusov. Currently heads the Department of Biophysics of the Biological Faculty A.B. Ruby. And in the autumn of 1959, the first in the world Department of Biophysics, which began to train biophysicists from physicists (before that, biophysicists were trained from biologists or doctors). Academicians I.G. Petrovsky, I.E. Tamm, N.N. -chemist). On the part of the administration, the creation of specialization " biophysics» Dean Professor was embodied at the Faculty of Physics V.S. Fursov, who supported its development all the years, and his deputy V.G. Zubov. The first employees of the department were a physico-chemist L.A. Blumenfeld, who headed the department for almost 30 years and is now its professor, biochemist S.E. Shnol, professor of the department, and physiologist I.A. Kornienko.

In the autumn of 1959, the world's first department of biophysics was created at the Faculty of Physics of Moscow University, which began to train specialists in biophysics from physicists. During the existence of the department, about 700 biophysicists have been trained.

The first employees of the department were physico-chemist L.A. Blumenfeld (1921 - 2002), who headed the department for 30 years, biochemist S.E. Shnol, professor of the department, and physiologist I.A. Kornienko. They formulated the principles of building a system of biophysical education for physicists, laid down the main directions of scientific research at the department.

At the Department of Biophysics L.A. For many years Blumenfeld gave lecture courses "Physical Chemistry", "Quantum Chemistry and the Structure of Molecules", "Selected Chapters of Biophysics". Author of more than 200 works, 6 monographs.

Scientific interests of V.A. Tverdislov are connected with the biophysics of membranes, with the study of the role of inorganic ions in biological systems, the mechanisms of ion transfer through cell and model membranes using ion pumps. He proposed and experimentally developed a model for the parametric separation of liquid mixtures in periodic fields in heterogeneous systems.

In terms of the scale of the Faculty of Physics, the Department of Biophysics is small, but historically it turned out that the research of its employees overlaps a significant area of ​​fundamental and applied biophysics. There are significant achievements in the field of studying the physical mechanisms of energy conversion in biological systems, radio spectroscopy of biological objects, the physics of enzymatic catalysis, biophysics of membranes, the study of aqueous solutions of biomacromolecules, the study of self-organization processes in biological and model systems, the regulation of basic biological processes, in the field of medical biophysics, nano - and bioelectronics, etc. For many years, the Department of Biophysics has been cooperating with universities and leading scientific laboratories in Germany, France, England, the USA, Poland, the Czech Republic and Slovakia, Sweden, Denmark, China, and Egypt.

1.7. Biophysical research in physics

The interest of physicists in biology in the 19th century. increased continuously. At the same time, in the biological disciplines, the attraction to physical methods of research intensified, they increasingly penetrated into the most diverse areas of biology. With the help of physics, the information capabilities of the microscope are expanded. In the early 30s of the XX century. the electron microscope appears. Radioactive isotopes, the ever-improving spectral technique, and X-ray diffraction analysis are becoming an elective tool for biological research. The scope of X-ray and ultraviolet rays is expanding; electromagnetic oscillations are used not only as a means of research, but also as factors influencing the body. Widely penetrates into biology and, especially physiology, electronic technology.

Along with the introduction of new physical methods, molecular biophysics is also developing. Having achieved tremendous success in understanding the essence of inanimate matter, physics begins to claim, using traditional methods, to decipher the nature of living matter. In molecular biophysics, very broad theoretical generalizations are created with the involvement of a complex mathematical apparatus. Following the tradition, the biophysicist seeks to get away from a very complex ("dirty") biological object in an experiment and prefers to study the behavior of substances isolated from organisms in the purest possible form. The development of various models of biological structures and processes - electrical, electronic, mathematical, etc. - is developing greatly. Models of cell movement are being created and studied (for example, a mercury drop in an acid solution makes rhythmic movements, like an amoeba), permeability, and nerve conduction. Much attention is attracted, in particular, by the model of nerve conduction created by F. Lilly. This is an iron wire ring placed in a solution of hydrochloric acid. When a scratch is applied to it, destroying the surface layer of oxide, an electric potential wave arises, which is very similar to the waves traveling along the nerves when excited. Many studies (starting from the 1930s) have been devoted to the study of this model, using mathematical methods of analysis. In the future, a more advanced model based on cable theory is created. The basis of its construction was some physical analogy between the distribution of potentials in an electrical cable and a nerve fiber.

Other areas of molecular biophysics are less popular. Among them, it should be noted mathematical biophysics, the leader of which is N. Rashevsky. In the USA, the Rashevsky school publishes the journal Mathematical Biophysics. Mathematical biophysics is related to many areas of biology. It not only describes in mathematical form the quantitative patterns of such phenomena as growth, cell division, excitation, but also attempts to analyze the complex physiological processes of higher organisms.

1.8. Biophysical research in biology

A strong impetus for the formation of biophysics was the emergence in the late XIX - early XX century. physical chemistry, dictated by the need to identify the mechanisms underlying the chemical interaction. This new discipline immediately attracted the attention of biologists by the fact that it opened up the possibility of understanding the physicochemical processes in those “dirty” living systems from the point of view of a physicist, with which it was difficult for them to work. A number of trends that have arisen in physical chemistry have given rise to similar trends in biophysics.

One of the biggest developments in the history of physical chemistry was the development S. Arrhenius (Nobel Prize, 1903) theory of electrolytic dissociation of salts in aqueous solutions (1887), which revealed the reasons for their activity. This theory aroused the interest of physiologists, who were well aware of the role of salt in the phenomena of excitation, the conduction of nerve impulses, in blood circulation, and so on. Already in 1890, the young physiologist V.Yu. Chagovets presents a study "On the application of the theory of Arrhenius dissociation to electromotive phenomena in living tissues", in which he tried to connect the occurrence of bioelectric potentials with an uneven distribution of ions.

A number of founders of physical chemistry take part in the transfer of physicochemical ideas to biological phenomena. Based on the phenomenon of movement of salt ions, W. Nernst (1908) formulated his well-known quantitative law of excitation: the threshold of physiological excitation is determined by the number of transferred ions. The physicist and chemist W. Ostwald developed a theory of the emergence of bioelectric potentials based on the assumption that a membrane that is semi-permeable to ions and capable of separating ions of opposite charges is present on the cell surface. Thus, the foundations of the biophysical direction in the interpretation of the permeability and structure of biological membranes in a broad sense were laid.

Chapter II. BIOPHYSICS IN PHYSICS LESSONS

2.1. Elements of biophysics in physics lessons in grades 7-9

A characteristic feature of modern science is the intensive interpenetration of ideas, theoretical approaches and methods inherent in different disciplines. This is especially true for physics, chemistry, biology and mathematics. Thus, physical research methods are widely used in the study of living nature, and the uniqueness of this object brings to life new, more advanced methods of physical research.

Considering the connections between physics and biology, it is necessary to show students the commonality of a number of laws of animate and inanimate nature, to deepen their understanding of the unity of the material world, the relationship and conditionality of phenomena, their cognizability, to familiarize them with the use of physical methods in the study of biological processes.

In physics lessons, it is necessary to emphasize that a characteristic sign of our time is the emergence of a number of complex sciences. Biophysics has developed - a science that studies the effect of physical factors on living organisms.

Attracting biophysical examples serves to better assimilate the course of physics. Biophysical material should be directly related to the curriculum of courses in physics and biology and reflect the most promising areas in the development of science and technology. A large number of biophysical examples can be selected for almost all sections of the physics course, it is advisable to use them along with examples from inanimate nature and from technology.

2.2. The use of biophysics in the classroom in elementary school

Mechanics

Movement and forces.

When studying the topic "Movement and Forces" in grade 7, you can introduce students to the speeds of movement of different animals. The snail crawls about 5.5 m in 1 hour. The turtle moves at a speed of about 70 m/h. A fly flies at a speed of 5 m/s. The average walking speed is about 1.5 m/s, or about 5 km/h. The horse is able to move at a speed of 30 km / h and above.

The maximum speed of some animals: a hound dog - 90 km / h, an ostrich - 120 km / h, a cheetah - 110 km / h, an antelope - 95 km / h.

Using the speed data of different representatives of the animal world, it is possible to solve various kinds of problems. For example:

The speed of the cochlea is 0.9 mm/s. Express this speed in cm/min, m/h.

The peregrine falcon, chasing prey, dives at a speed of 300 km / h. What distance does it travel in 5 seconds?

It is known that the average growth rate of oak is approximately 0.3 m per year. How old is an oak 6.3 m high?

Tel weight Density.

Body weight and volume are directly related to representatives of the flora, for example, the following tasks are given:

Determine the mass of birch wood if its volume is 5 m 3.

Determine the volume of dry bamboo if its mass is 4800 kg.

Determine the density of a balsa tree if its mass is 50 tons and its volume is 500 m 3.

Gravity.

When studying this topic, you can conduct the following training work. The masses of different mammals are given: whale - 70000 kg, elephant - 4000 kg, rhino - 2000 kg, bull - 1200 kg, bear - 400 kg, pig 200 kg, human - 70 kg, wolf - 40 kg, hare - 6 kg. Find their weight in newtons.

The same data can be used to graphically depict forces.

Pressure of liquids and gases.

On the human body, the surface area of ​​which, with a mass of 60 kg and a height of 160 cm, is approximately equal to 1.6 m 2, a force of 160,000 N, due to atmospheric pressure, acts. How does the body withstand such a huge load?

This is achieved due to the fact that the pressure of the fluids filling the vessels of the body balances the external pressure.

Closely related to this issue is the possibility of being underwater at great depths. The fact is that transferring the body to another level causes a breakdown of its functions. This is due to the deformation of the walls of the vessels, designed for a certain pressure from the inside and outside. In addition, when the pressure changes, the rate of many chemical reactions also changes, as a result of which the chemical balance of the body also changes. When the pressure increases, there is an increased absorption of gases by body fluids, and when it decreases, the release of dissolved gases occurs. With a rapid decrease in pressure due to the intense release of gases, the blood boils, as it were, which leads to blockage of blood vessels, often fatal. This determines the maximum depth at which diving operations can be carried out (as a rule, not lower than 50 meters). The descent and raising must be very slow so that the release of gases occurs only in the lungs, and not immediately in the entire circulatory system.

Examples of some powers in wildlife.

The power of the fly in flight is 10 -5 watts.

Swordfish strike 10 5 -10 6 W.

It is believed that a person under normal working conditions can develop a power of about 70-80 W, but a short-term increase in power by several times is possible. So, a person of 750 N can jump to a height of 1 m in 1 s, which corresponds to a power of 750 W; the runner develops a power of about 1000 watts.

Instantaneous, or explosive, release of energy is possible in sports such as shot put or high jump. Observations have shown that during high jumps with simultaneous repulsion with both legs, some men develop an average power of about 3700 W for 0.1 s, and women - 2600 W.

Heart-lung machine (AIC)

Finishing the study of mechanics, it is useful to tell students about the device of the heart-lung machine.

During operations on the heart, it often becomes necessary to temporarily turn it off from the circulation in the body (about 4-5 liters for an adult patient), the set temperature of the circulating blood.

The heart-lung machine consists of two main parts: parts of the pump and the oxygen generator. Pumps perform the functions of the heart - they maintain pressure and blood circulation in the vessels of the body during surgery. The oxygen generator performs the function of the lungs and ensures blood saturation of at least 95% and maintains a partial pressure of CO 2 at the level of 35-45 mm Hg. Art. venous blood from the patient's vessels flows by gravity into an oxygen generator located below the level of the operating table, where it is saturated with oxygen, freed from excess carbon dioxide, and then pumped into the patient's bloodstream by an arterial pump. AIK for a long time is able to replace the functions of the heart and lungs.

When solving problems related to living objects, great care must be taken to prevent misinterpretation of biological processes.

A task. How to explain with the help of physical representations that in a storm a spruce tree is easily uprooted, while a pine trunk is more likely to break?

We are interested in analyzing only the qualitative side of the issue. In addition, we are interested in the question of the comparative behavior of both trees. The role of the load in our problem is played by the wind force F B. You can add the wind force acting on the trunk to the wind force acting on the crown, and even assume that the wind forces acting on both trees are the same. Then, apparently, further reasoning should be as follows. The root system of pine goes deeper into the ground than that of spruce. Due to this, the shoulder of the force holding the pine in the ground is greater than that of the spruce. Therefore, to turn a spruce with a root, less moment of force and wind is required than to break it. Therefore, spruce turns out with the root more often than pine, and pine breaks more often than spruce.

The study of heat and molecular phenomena

Device "artificial kidney"

This device is used for emergency medical care for acute intoxication; to prepare patients with chronic renal failure for kidney transplantation; for the treatment of certain disorders of the nervous system (schizophrenia, depression).

AIP is a hemodialyzer in which blood comes into contact with a saline solution through a semi-permeable membrane. Due to the difference in osmotic pressures, ions and molecules of metabolic products (urea and uric acid), as well as various toxic substances to be removed from the body, pass through the membrane from the blood into the saline solution.

capillary phenomena.

When considering capillary phenomena, their role in biology should be emphasized, since most plant and animal tissues are permeated with an enormous number of capillary vessels. It is in the capillaries that the main processes associated with the respiration and nutrition of the body take place, all the most complex chemistry of life, closely related to diffuse phenomena.

A system of many branched tubes with elastic walls can serve as a physical model of the cardiovascular system. As the branching increases, the total cross section of the tubes increases, and the velocity of the fluid decreases accordingly. However, due to the fact that the bifurcation consists of many narrow channels, the internal friction losses increase greatly and the total resistance to the movement of fluids (despite the decrease in speed) increases significantly.

The role of surface phenomena in the life of living nature is very diverse. For example, the surface film of water is a support for many organisms when moving. This form of movement is found in small insects and arachnids. Some animals that live in water, but do not have gills, are suspended from below at the surface film of water with the help of special non-wettable bristles surrounding their respiratory organs. This technique is used by mosquito larvae (including malaria).

For independent work, you can offer tasks such as:

How can knowledge of molecular kinetic theory be applied to explain the mechanism by which plant root hairs absorb nutrients from the soil?

How to explain the water resistance of a thatched roof, hay in stacks?

Determine the height to which, under the action of surface tension forces, water rises in the stems of plants that have capillaries with a diameter of 0.4 mm. Can capillarity be considered the only reason for the rise of water along the stem of a plant?

Is it true that swallows flying low above the ground herald the approach of rain?

The study of vibrations and sound

Examples of periodic processes in biology: many flowers close corollas at nightfall; in most animals, there is a periodicity in the appearance of offspring; periodic changes in the intensity of photosynthesis in plants are known; fluctuations experience the size of nuclei in cells, etc.

Forest sounds.

The sounds of the forest (rustle) arise due to the vibration of the leaves under the influence of the wind and their friction against each other. This is especially noticeable on aspen leaves, as they are attached to long and thin petioles, therefore they are very mobile and sway even with the weakest air currents.

Frogs have very loud and quite varied voices. Some species of frogs have interesting sound amplification devices in the form of large spherical bubbles on the sides of their heads, which swell when they cry and serve as strong resonances.

The sound of insects is most often caused by the rapid vibrations of the wings during flight (mosquitoes, flies, bees). The flight of the insect that flaps its wings more often is perceived by us as a sound of higher frequency and, therefore, higher. Some insects, such as grasshoppers, have special organs of sound - a row of cloves on the hind legs that touch the edges of the wings and cause them to vibrate.

A worker bee flying out of the hive for a bribe makes an average of 180 wing beats per second. When she returns with a load, the number of strokes increases to 280. How does this affect the sound we hear?

Why is the flight of a butterfly silent?

Many frogs are known to have large, spherical blisters on the sides of their heads that swell when they call. What is their purpose?

What determines the frequency of the sound emitted by insects during flight?

The study of optics and the structure of the atom.

Light.

Light is absolutely necessary for living nature, since it serves as a source of energy for it. Chlorophyll-bearing plants, with the exception of some bacteria, are the only organisms capable of synthesizing their own substance from water, mineral salts and carbon dioxide with the help of radiant energy, which they convert into chemical energy in the process of assimilation. All other organisms that inhabit our planet - plants and animals - directly or indirectly depend on chlorophyll-bearing plants. They most strongly absorb the rays corresponding to the absorption bands in the spectrum of chlorophyll. There are two of them: one lies in the red part of the spectrum, the other in the blue-violet. The remaining rays of the plant reflect. It is they who give chlorophyll-bearing plants their green color. Chlorophyll-bearing plants are represented by higher plants, mosses and algae.

Eyes of various representatives of the animal world.

In amphibians, the cornea of ​​the eye is very convex. Accommodation of the eyes is carried out, as in fish, by the movement of the lens.

Birds have very sharp eyesight, superior to that of other animals. Their eyeball is very large and has a peculiar structure, due to which the field of view increases. Birds with especially sharp eyesight (vultures, eagles) have an elongated "telescopic" eyeball. The eyes of mammals living in the water (for example, whales) resemble the eyes of deep-sea fish in terms of the bulge of the cornea and the large refractive index.

How bees see colors.

The vision of bees is different from that of humans. A person distinguishes about 60 individual colors of the visible spectrum. Bees distinguish only 6 colors: yellow, blue-green, blue, "purple", violet and ultraviolet invisible to humans. Bee "magenta" color is a mixture of yellow and ultraviolet rays of the spectrum, visible to the bee.

For independent work on this section, you can offer the following tasks:

What are two eyes for?

The retina of a human and an eagle eye is approximately the same, but the diameter of the nerve cells (cones) in the eagle's eye in its central part is smaller - only 0.3 - 0.4 microns (microns = 10 -3 mm). What is the significance of such a structure of the retina of the eagle's eye?

As darkness falls, the pupil of the eye dilates. How does this affect the sharpness of the image of surrounding objects? Why?

The lens of a fish eye is spherical. What features of the fish habitat make this form of the lens appropriate? Think about the accommodation mechanism of the eyes in fish if the curvature of the lens does not change.

2.3. Blitz Tournament "Physics in Wildlife"

To organize independent practical activities for students of the 7th grade, a blitz tournament "Physics in wildlife" can be offered.

The purpose of the lesson: repetition of the material on the topic “Generalizing lesson for the entire course”; test of knowledge, ingenuity, ability to think logically.

Rules of the game

Questions are selected throughout the 7th grade course.

The lesson goes at a fast pace.

During the lesson, you can use any reference literature, including the textbook.

During the classes

The teacher reads the question. The player, ready to answer, raises his hand; The first person to raise their hand is given the floor. The correct answer is worth 1 point. The participants with the least points are eliminated from the game.

Questions:

When leaving the water, the animals are shaken. What physical law is used in this case? (Law of inertia).

What is the significance of the elastic hair on the soles of the hare's feet? (Elastic hair on the soles of the hare's feet lengthens the braking time when jumping and therefore weakens the force of impact).

Why do some fish hold their fins close to them when moving fast? (To reduce the resistance to movement).

In autumn, a poster is sometimes hung near tram tracks passing near gardens and parks: “Caution! Leaf fall. What is the meaning of this warning? (Leaves falling on the rails reduce friction, so the car can go a long way when braking.)

What is the compressive strength of human bone? (The femur, for example, placed vertically, can withstand the pressure of a load of one and a half tons).

Why are diving boots made with heavy lead soles? (The heavy lead soles of the boots help the diver overcome the buoyancy of the water.)

Why can a person slip when stepping on a hard, dry pea? (Friction contributes to the movement of a person. A dry pea, being like a bearing, reduces friction between the person's legs and the support).

Why, in a river with a muddy bottom, do we get stuck more in a shallow place than in a deep one? (Plunging to a greater depth, we displace a larger volume of water. According to the law of Archimedes, a large buoyant force will act on us in this case).

Summarizing.

The teacher gives grades.

Conclusion

K. D. Ushinsky wrote that some teachers seem to only do what they repeat, but in fact they are rapidly moving forward in learning new things. Repetition with the involvement of the new leads to a better understanding and memorization of the material covered. It is also known that the best way to generate interest in a subject is to apply the acquired knowledge in other areas than those in which they were received. The organization of repetition with the involvement of biophysical material is just such a type of repetition, when it occurs with the involvement of a new one, is of great interest to students and allows them to apply the laws of physics to the field of wildlife.

Attracting biophysical examples serves to better assimilate the course of physics. Biophysical material should be directly related to the curriculum of courses in physics and biology and reflect the most promising areas in the development of science and technology.

The establishment of interdisciplinary connections between physics and biology provides great opportunities for the formation of materialistic beliefs. Schoolchildren learn to illustrate the laws of physics not only with examples from technology, but also with examples from wildlife. On the other hand, considering the vital activity of plant and animal organisms, they use physical laws, physical analogies.

Repetition and consolidation of the material covered with the involvement of biophysical material enables the teacher to acquaint students with the latest achievements in the field of biophysics and bionics, to encourage them to read additional literature.

Organizationally, the lesson can be built in different ways: in the form of lectures by teachers, in the form of reports prepared by students under the guidance of teachers of physics and biology.

BIBLIOGRAPHY

Trofimova T.I. Collection of tasks on the course of physics for technical universities - 3rd ed. - M .: LLC Publishing House Onyx 21st Century: LLC Publishing House Mir and Education, 2003 - 384 p.: ill.

Zorin N.I. Elective course "Elements of Biophysics": Grade 9. - M.: VAKO, 2007. - 160 p. - (Teacher's workshop).

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One of the most ancient sciences is, of course, biology. People's interest in the processes occurring within themselves and the surrounding beings arose several thousand years before our era.

Observation of animals, plants, natural processes was an important part of people's lives. Over time, a lot of knowledge has accumulated, methods of studying wildlife and the mechanisms that occur in it have been improved and developed. This led to the emergence of many sections that make up a complex science in total.

Biological research in various areas of life makes it possible to obtain new valuable data that are important for understanding the structure of the planet's biomass. Use this knowledge for practical human purposes (space exploration, medicine, agriculture, chemical industry, and so on).

Many discoveries made it possible to make biological research in the field of the internal structure and functioning of all living systems. The molecular composition of organisms, their microstructure has been studied, many genes have been isolated and studied from the genome of humans and animals, plants. The merits of biotechnology, cellular and allow you to get several harvests of plants per season, as well as to breed animal breeds that give more meat, milk and eggs.

The study of microorganisms made it possible to obtain antibiotics and create tens and hundreds of vaccines that allow defeating many diseases, even those that used to take thousands of lives in epidemics of people and animals.

Therefore, the modern science of biology is the limitless possibilities of mankind in many branches of science, industry and health preservation.

Classification of biological sciences

One of the very first appeared private sections of the science of biology. Such as botany, zoology, anatomy and taxonomy. Later, disciplines more dependent on technical equipment began to form - microbiology, virology, physiology, and so on.

There are a number of young and progressive sciences that emerged only in the 20th-21st century and play an important role in the modern development of biology.

There is not one, but several classifications by which biological sciences can be ranked. Their list is quite impressive in all cases, consider one of them.

Biology	Private sciences	Botany	deals with the study of the external and internal structure, physiological processes, phylogenesis and distribution in nature of all plants existing on the planet (flora)	Includes the following sections: algology; dendrology; taxonomy; anatomy; morphology; physiology; bryology; paleobotany; ecology; geobotany; ethnobotany; plant reproduction.
		Zoology	deals with the study of the external and internal structure, physiological processes, phylogenesis and distribution in nature of all animals existing on the planet (fauna)	Disciplines included in: Disciplines: topographic anatomy; comparative; systematic; age; plastic; functional; experimental.
		Anthropology	a number of disciplines that study the development and formation of a person in a biological and social environment in a complex	Sections: philosophical, judicial, religious, physical, social, cultural, visual.
		Microbiology	studies the smallest living organisms, from bacteria to viruses	Disciplines: virology, bacteriology, medical microbiology, mycology, industrial, technical, agricultural, space microbiology
		General Sciences	Systematics	the tasks include developing the basis for the classification of all life on our planet with the aim of strict ordering and identification of any representative of the biomass
	Morphology		description of external signs, internal structure and topography of the organs of all living beings	Sections: plants, animals, microorganisms, fungi
	Physiology		studies the features of the functioning of a particular system, organ or part of the body, the mechanisms of all processes that ensure its vital activity	Plants, animals, human, microorganisms
	Ecology		the science of the relationship of living beings with each other, the environment and man	Geoecology, general, social, industrial
	Genetics		studies the genome of living beings, the mechanisms of heredity and variability of traits under the influence of various conditions, as well as historical changes in the genotype during evolutionary transformations
	biogeography		considers the resettlement and distribution of certain species of living beings on the planet
	evolutionary doctrine		reveals the mechanisms of the historical development of man and other living systems on the planet. Their origin and development
	Complex sciences that arose at the junction with each other	Biochemistry	studies the processes occurring in the cells of living beings from a chemical point of view
		Biotechnology	considers the use of organisms, their products and or parts for human needs
		Molecular biology	studies the mechanisms of transmission, storage and use of hereditary information by living beings, as well as the functions and fine structure of proteins, DNA and RNA.	Related sciences: genetic and cell engineering, molecular genetics, bioinformatics, proteomics, genomics
		Biophysics	it is a science that studies all possible physical processes occurring in all living organisms, from viruses to humans	Sections of this discipline will be discussed below.

Thus, we have tried to capture the main diversity that is the biological sciences. This list with the development of technology and methods of study is expanding and replenishing. Therefore, a unified classification of biology does not exist today.

Progressive biosciences and their significance

The youngest, modern and progressive sciences of biology include such as:

• biotechnology;
• molecular biology;
• space biology;
• biophysics;
• biochemistry.

Each of these sciences was formed no earlier than the 20th century, and therefore is rightfully considered young, intensively developing and the most significant for practical human activity.

Let us dwell on such of them as biophysics. This is a science that appeared around 1945 and became an important part of the entire biological system.

What is biophysics?

To answer this question, first of all, it is necessary to point out its close contact with chemistry and biology. In some issues, the boundaries between these sciences are so close that it is difficult to make out which of them is specifically involved and in priority. Therefore, it is worth considering biophysics as a complex science that studies the deep physical and chemical processes occurring in living systems at the level of both molecules, cells, organs, and at the level of the Biosphere as a whole.

Like any other, biophysics is a science that has its own object of study, goals and objectives, as well as worthy and significant results. In addition, this discipline is closely correlated with several new directions.

Objects of study

For biophysics they are biosystems at different organizational levels.

1. viruses, unicellular fungi and algae).
2. The simplest animals.
3. Individual cells and their structural parts (organelles).
4. Plants.
5. Animals (including humans).
6. ecological communities.

That is, biophysics is the study of the living from the point of view of the physical processes occurring in it.

The tasks of science

Initially, the tasks of biophysicists were to prove the existence of physical processes and phenomena in the life of living beings and to study them, finding out their nature and significance.

Modern tasks of this science can be formulated as follows:

1. To study the structure of genes and the mechanisms that accompany their transmission and storage, modifications (mutations).
2. Consider many aspects of cell biology (the interaction of cells with each other, chromosomal and genetic interactions, and other processes).
3. To study polymer molecules (proteins, nucleic acids, polysaccharides) in combination with molecular biology.
4. To reveal the influence of cosmogeophysical factors on the course of all physical and chemical processes in living organisms.
5. More deeply reveal the mechanisms of photobiology (photosynthesis, photoperiodism, and so on).
6. Implement and develop methods of mathematical modeling.
7. Apply the results of nanotechnology to the study of living systems.

From this list, it is obvious that biophysics studies a lot of significant and serious problems of modern society, and the results of this science are of great importance for a person and his life.

History of formation

As a science, biophysics was born relatively recently - in 1945, when he published his work "What is life from the point of view of physics." It was he who first noticed and indicated that many laws of physics (thermodynamic, laws of quantum mechanics) take place precisely in the life and work of organisms of living beings.

Thanks to the work of this man, the science of biophysics began its intensive development. However, even earlier, in 1922, an institute of biophysics was created in Russia, headed by P.P. Lazarev. There, the main role is assigned to the study of the nature of excitation in tissues and organs. The result was the identification of the importance of ions in this process.

1. Galvani discovers electricity and its significance for living tissues (bioelectricity).
2. A. L. Chizhevsky is the father of several disciplines studying the influence of space on the Biosphere, as well as ionization radiation and electrohemodynamics.
3. The detailed structure of protein molecules was studied only after the discovery of X-ray diffraction analysis (X-ray diffraction analysis). This was done by Perutz and Kendrew (1962).
4. In the same year, the three-dimensional structure of DNA was discovered (Maurice Wilkins).
5. Neher and Zakman in 1991 managed to develop a method for local fixation of the electric potential.

Also, a number of other discoveries allowed the science of biophysics to embark on the path of intensive and progressive modernization in development and formation.

Sections of biophysics

There are a number of disciplines that make up this science. Let's consider the most basic of them.

1. Biophysics of complex systems - considers all the complex mechanisms of self-regulation of multicellular organisms (systemogenesis, morphogenesis, synergogenesis). Also, this discipline studies the features of the physical component of the processes of ontogenesis and evolutionary development, the levels of organization of organisms.
2. Bioacoustics and biophysics of sensory systems - studies the sensory systems of living organisms (vision, hearing, reception, speech, and others), ways of transmitting various signals. Reveals the mechanisms of energy conversion when organisms perceive external influences (irritations).
3. Theoretical biophysics - includes a number of subsciences involved in the study of the thermodynamics of biological processes, the construction of mathematical models of the structural parts of organisms. Also considers kinetic processes.
4. Molecular biophysics - considers the deep mechanisms of the structural organization and functioning of such biopolymers as DNA, RNA, proteins, polysaccharides. He is engaged in the construction of models and graphic images of these molecules, predicts their behavior and formation in living systems. Also, this discipline builds supramolecular and submolecular systems in order to determine the mechanism of construction and action of biopolymers in living systems.
5. Biophysics of the cell. He studies the most important cellular processes: differentiation, division, excitation and biopotentials of the membrane structure. Particular attention is paid to the mechanisms of membrane transport of substances, potential difference, properties and structure of the membrane and its surrounding parts.
6. Biophysics of metabolism. The main ones under consideration are solarization and adaptation of organisms to it, hemodynamics, thermoregulation, metabolism, and the influence of ionization rays.
7. Applied Biophysics. It consists of several disciplines: bioinformatics, biometrics, biomechanics, the study of evolutionary processes and ontogenesis, pathological (medical) biophysics. The objects of study of applied biophysics are the musculoskeletal system, methods of movement, methods of recognizing people by physical features. Medical biophysics deserves special attention. It considers pathological processes in organisms, methods of reconstruction of damaged sections of molecules or structures or their compensation. Gives material for biotechnology. It is of great importance in the prevention of the development of diseases, especially of a genetic nature, their elimination and explanation of the mechanisms of action.
8. Habitat biophysics - studies the physical effects of both the local habitats of beings and the effects of near and far space entities. Also considers biorhythms, the influence of weather conditions and biofields on creatures. Develops measures to prevent negative impacts

All these disciplines make an enormous contribution to the development of understanding the mechanisms of life of living systems, the influence of the biosphere and various conditions on them.

Modern achievements

Some of the most significant events that relate to the achievements of biophysics can be named:

• revealed the mechanisms of cloning organisms;
• the features of transformations and the role of nitric oxide in living systems have been studied;
• the relationship between small and messenger RNAs has been established, which in the future will make it possible to find a solution to many medical problems (elimination of diseases);
• discovered the physical nature of autowaves;
• thanks to the work of molecular biophysicists, aspects of DNA synthesis and replication have been studied, which led to the possibility of creating a number of new drugs for serious and complex diseases;
• computer models of all reactions accompanying the process of photosynthesis have been created;
• methods of ultrasonic research of an organism are developed;
• the connection between cosmogeophysical and biochemical processes has been established;
• predicted climate change on the planet;
• discovery of the significance of the enzyme urokenase in the prevention of thrombosis and the elimination of consequences after strokes;
• also made a number of discoveries on the structure of the protein, the circulatory system and other parts of the body.

Institute of Biophysics in Russia

In our country, they exist. M. V. Lomonosov. The Faculty of Biophysics operates on the basis of this educational institution. It is he who trains qualified specialists for work in this area.

It is very important to give a good start to future professionals. They have a tough job ahead of them. A biophysicist is obliged to understand all the intricacies of the processes occurring in living beings. In addition, students must understand physics. After all, this is a complex science - biophysics. Lectures are structured in such a way as to cover all the disciplines related to and constituting biophysics, and cover consideration of both biological and physical issues.