Marina Chernysheva Temporal structure of biosystems and biological time
St. Petersburg State University
M. P. Chernysheva
TEMPORAL STRUCTURE of biosystems and biological TIME
Super Publishing
Introduction
The nature of Time is one of the global problems to which science has repeatedly returned throughout the history of its existence. The evolution of ideas about Time from antiquity to the 20th century is deeply analyzed in the classic work of J. Withrow “Natural Philosophy of Time” (1964), in the monographs of M. I. Elkin (1985), P. P. Gaidenko (2006) and other authors . Since the twentieth century, the philosophical aspects of this problem have been invariably associated with natural scientific approaches to its solution (Schrodinger, 2002; Chizhevsky, 1973; Winfrey, 1986; Kozyrev, 1963, 1985, 1991; Prigozhin, 2002; etc.). In the works of outstanding Russian researchers we find ideas that gave rise to entire trends in the science of time. Thus, I.M. Sechenov initiated research on the influence of physical activity on a person’s subjective time. I.P. Pavlov, who first described the time reflex, actually declared the brain’s ability to remember time intervals. N.P. Perna (1925), an employee of the Department of Physiology at Petrograd University, was the first to describe the rhythms of a number of human physiological processes. D.I. Mendeleev, who described the movement of a flower following a change in the position of the sun, definitely demonstrated the presence of a circadian (circadian) rhythm of plant movements, the hormonal mechanism of which was described later (V.N. Polevoy, 1982). The works of A. A. Ukhtomsky trace the idea of the importance of the time factor in the work of the nervous system and, in particular, in the formation of the dominant (Ukhtomsky, 1966; Sokolova, 2000). One of the geniuses of the Russian Renaissance of the early twentieth century, V.I. Vernadsky, not only introduced the rubrication of time specific to different systems (geological, historical, biological, social), but also substantiated the idea of biological time as basic and primary, giving it a “cosmic” status” due to the ability of biosystems to move and reproduce (Vernadsky, 1989). This same feature of living organisms was emphasized by E. Schrödinger (2002).
Along with multidisciplinary approaches to solving the problem of the nature of Time (Aksenov, 2000; Vakulenko et al., 2008; Kazaryan, 2009; Koganov, 2009; Kozyrev, 1989; Korotaev, Kiktenko, 2012; Lebedev, 2004; Levich, 2000, 2002, 2013 ; Khasanov, 2011; Churakov, 2012; Shikhobalov, 2008, etc.), a huge amount of research, starting from the second half of the twentieth century, has been devoted to the nature of biological time (Aschoff, 1960; Winfrey, 1990; Pittendrich, 1984; Alpatov, 2000; Romanov, 2000; Olovnikov, 1973, 2009; Skulachev, 1995; Zaguskin, 2004, 2007, etc.). Achievements in physics, chemistry, mathematics and biology predetermined the development of various new research methods, which made it possible to discover clock-genes proteins, which form the mechanism of circadian rhythms for many body functions. The importance of the activity of clock proteins and the clock oscillator for human health and adaptation to the space-time continuum of the environment has determined the corresponding thematic focus of most of the works of modern domestic and foreign researchers. In Russian biology and medicine, the “assault” of the cellular-molecular mechanisms of biological time led to outstanding discoveries: the creation of the telomere-redusomal theory of life expectancy control (Olovnikov, 1973, 2009) and the idea of the role of mitochondria in the aging process (Skulachev, 1995), as well as to the development of gerontological aspects of the role of hormones of the pineal gland and thymus (Anisimov, 2010; Khavinson et al., 2011; Kvetnoy et al., 2011). The works of foreign researchers have identified the functions of individual clock proteins, the conditions for the formation of the clock oscillator and rhythms with different temporal parameters (see Golombek et al., 2014), and also developed ideas about the synchronization systems of clock oscillators at different structural levels of the body. A growing understanding of the specifics of cellular, tissue, organ and system generators of temporal processes determines the beginning return of foreign authors to “systems thinking” in the aspect of the problem of Time (Blum et al., 2012; Mohawk et al., 2012). Note that a systematic approach to the study of this problem has always remained in the field of attention of domestic researchers (Chernigovsky, 1985; Barannikova et al., 2003; Kulaev, 2006; Yanvareva et al., 2005; Zhuravlev, Safonova, 2012, etc.) . Along with obvious successes in the study of biological objects sensitive to the “pass of time” (N.A. Kozyrev’s term), questions about the temporal structure of living organisms, the relationship of cellular-molecular and system timers, Time sensors remain poorly developed, and the question of the nature of Time remains open . According to the author, a wide range of studies of biosystems carried out to date in the world allows us to propose certain solutions to the listed issues.
Biological time
“To understand the “nature” of time means to indicate its natural referent, i.e., a process, phenomenon, “carrier” in the material world, the properties of which could be identified or corresponded with the properties attributed to the phenomenon of time.”
A.P. Levich, 2000.
1.1. Phenomenon of life
The statement of Alexander Petrovich Levich included in the epigraph seems completely fair in the light of the ideas of G. Leibniz and N.A. Kozyrev about the energetic nature of time and its “active properties”. Indeed, by analogy with the history of the discovery of the electron along the immersion trail in a cloud chamber, biological processes that have a number of temporal parameters and therefore are essentially temporal processes may well be “referents” of time and reflect its impact. To understand the “nature” of time in biosystems, it is important to analyze the factors that determine the specificity of living organisms in comparison with inert systems
The phenomenon of life and the differences between a living organism and inert systems have always attracted the attention of philosophers and representatives of the natural sciences (Aristotle, 1937; Strakhov, 2008; Vernadsky, 1989; Ukhtomsky, 1966; Schrödinger, 2002, and many others). It is obvious that the generality of the basic laws of nature does not exclude the peculiarities of their manifestation under the specific conditions of a biosystem, inert natural or artificial systems. These include, first of all, the laws of thermodynamics, which determine for any system the possibility and duration of operation, as well as the time of existence (life expectancy). Recognizing the validity of the laws of thermodynamics for all objects of the Universe, many researchers note the specificity of manifestations of the second law of thermodynamics for living organisms (Schrödinger, 2002; Prigogine, 2002, etc.). Among these, first of all, the impossibility of “thermal death” for living organisms is noted due to the desire of biological systems to stabilize the level of entropy (Vernadsky, 1989; Prigozhin, 2002; Prigozhin, Stengers, 2000, etc.).
The life activity of biosystems is based on various processes that use chemical, mechanical, electrical, light and other types of energy. As is known, when implementing various functions (work) in any system, a partial conversion of one or another energy into heat occurs, which can be lost through heat dissipation into the environment or partially delayed, determining the level of chaos (entropy) in the structures of the body. Other well-known definitions of entropy are also valid for living organisms: as a measure of the degree of unstructuredness of energy flows and a measure of the thermodynamic possibility of a certain state or process. The multiplicity of possible definitions of entropy for a biosystem also emphasizes the diversity of ways of its regulation.
I.R. also drew attention to the possibility of the emergence of internal time for a complex system. Prigogine: in the case of self-organization, each such system coordinates its internal processes in accordance with its own time. Prigogine called this the relativism of system time and noted that as soon as a dissipative structure is formed, the homogeneity of space and time is violated. Moreover, he believed that living systems are endowed with the ability to sense the direction of time. This direction of time is also noted by psychology. We remember the past, but we don't remember the future!
Biological space and time characterize the features of the spatio-temporal parameters of the organization of matter: the biological existence of the human individual, the change of species of vegetation and animals, the phases of their development. Aristotle also distinguished two essences of time: one - as a parameter that records various states of motion of bodies, and the other - as birth and death, i.e. as a characteristic of the age of the system and, consequently, its direction from the past to the future.
Along with the linear perception of time, a person has a psychological sensation of the passage of time, due, among other things, to its internal organization. This representation is called biological time, or biological clock. Biological clocks reflect the rhythmic nature of processes in a living organism in the form of its reaction to the rhythms of nature and the entire Universe in general. The appearance of biological time, unique to each living system, is due to the synchronization of biochemical processes in the body.
Since a living organism is a hierarchical system, it must balance its functioning with the synchronization of all sublevels and subsystems not only in time, but also in biological space. This synchronization is associated with the presence of biorhythms in the system. The more complex the system, the more biorhythms it has. American cyberneticist N. Winner (1894-1964) believed that “it is the rhythms of the brain that explain our ability to sense time.”
Most physiological processes of growth, development, movement and metabolism in cells are subject to rhythmic changes caused by the daily (circadian) rhythm of the external environment. Thus, plants have well-known rhythmic cycles of closing flowers and lowering leaves at night and opening them during the day. However, this is not always due only to external exposure to light. Russian biophysicist S.E. Shnol gives a curious example with Maran's beans, the leaves of which would fall and rise in the evening and morning, even if it was in a completely dark room. The leaves seemed to “feel” time and determine it with their internal physiological clock. Typically, plants determine the length of the day by the transition of the phytochrome pigment from one form to another when the spectral composition of sunlight changes. The “sunset” sun is “red” because long-wave red light is scattered less than blue light. This sunset or twilight light contains a lot of red and infrared radiation, and plants (and maybe animals) sense it.
A person studying the world is himself a structure that changes over time, and for him, ideas about the past and the future are significantly different. In the past, time acts as a generalized coordinate, and in the future it has properties that depend on how we and other objects behave in the present. If the past is certain, then the future of complex systems is not completely known. As sociologist I.V. said Bestuzhev-Lada, “the past can be known, but cannot be changed, and the future can be changed, but cannot be known.” The more complex the structure, the greater the number of possible states it can take at future times. This is the ambiguity of time. In addition, time for an individual, for its species, genus, class, etc. various (time scale). For a person it is less, for humanity it is more. The “sense of time” for a living organism is always subjective: quickly when a person is carried away, slowly when idle.
These different forms of time and its impact on the characteristics of a person’s life and behavior should be manifested in his appearance and his other properties and qualities. Many psychological studies have clearly shown that depending on a person’s functional state, his own subjective time flows differently. The famous test pilot M. Gallay describes a case of studying the flutter phenomenon during an airplane flight. The pilot estimated the duration of his actions before the destruction of the aircraft and ejection at 50-55 seconds. However, when the “black box” was decrypted, it turned out that only 7 seconds had passed, i.e. For the pilot himself, time slowed down 7 times! Let us note that for an individual person, time does not act as an independent objective variable (astronomical time), but, on the contrary, as a parameter dependent on the person’s state. It is difficult for a person to perceive (and feel!) time as such (in a sense, it is an abstract concept for him). For living organisms, the passage of absolute time is devoid of reality. We perceive not time, but the processes and changes occurring during it, including evaluating the sequence of events.
The standard of time for a person is often his own internal time. Their own time is felt, for example, by Buddhist monks who spend a long time in dark caves, alone, without astronomical or ordinary earthly time sensors. Psychological research shows that in such cases people begin to live in their own time, and if this continued long enough, they could create their own historical chronology.
The study and modeling of physiological time should probably be associated with the formation of a new event-oriented biorhythmology, which takes into account the physiological essence of what is an event for a living organism and its own rhythmic patterns. Our physiological age does not depend on how many sunrises and sunsets we have seen throughout our lives. The intensity of life processes is associated with internal time, the biological clock. They also control such processes as the volume of the cell nucleus, the frequency of cell divisions, the intensity of photosynthesis and cellular respiration, the activity of biochemical processes, etc. It is assumed that this biological time can flow in different ways, unevenly, when compared with physical (astronomical) time. However, we note that to date such unevenness of time has not been experimentally discovered in the Universe as a whole.
The synchronized general biorhythm of the body may not coincide with the rhythm of astronomical time. At a young age, the body cycles more often, and psychologically it seems that astronomical time is moving slower, but in old age, biological time is moving slower and therefore it seems that astronomical time is moving faster. Now it’s clear why time flows differently for a child and an old person. The first one is slower, the second one is faster. A person’s sense of time is associated with the emotional coloring of the events occurring in him. That's why in childhood, when emotions are stronger, events seem longer. Pain lengthens time, happiness shortens it (“happy people don’t watch hours”). A certain conflict arises between physical and biological time. They say that a woman is only as old as she looks; and for a healthy person it doesn’t matter how old he is, what matters is how and how old he feels. Everything is individual!
In general, the health of the body is determined by the condition and number of its elementary “atoms” - cells. The rate of cell evolution, their growth and death will determine the lifespan of the organism. In youth, the rate of cell renewal is high; in old age it slows down, the time derivative of the number of new cells is less than zero, as physicists say. Life is characterized by the intensity of cell renewal, and with aging, biological time, programmed by the very evolution of life, slows down. The lifespan of cells is determined by the number of their divisions, specific to each species. For living organisms, there is experimental evidence that the rate of cell division, set by biorhythms, initially increases, as the organism develops it reaches a maximum value and then decreases, down to zero with the natural death of the organism. Cells and organs keep track of time in accordance with the program embedded in the genome.
And “if life has passed intensively, then it seems useful and interesting” (Russian biologist I. I. Mechnikov (1845-1916)). A similar thought was expressed by the French writer and philosopher A. Camus (1913-1966): “The years fly by quickly in youth because they are full of events, but in old age they drag on slowly because these events are predetermined.” Apparently, this allowed L. Landau to say justifiably before his death: “It seems that I lived my life well.” And for the author, the motto has always been: “Only an intense exchange of energy with the environment allows me to remain a creative person.” Russian biologist I. I. Arshavsky noted that the more active an organism is and with greater energy consumption, the longer its life expectancy.
Let us also note that random processes, the role of which is great in quantum statistics and biology, can be fully realized only in infinitely large time, and time itself is limited by the existence of the world.
Modern science also uses the concepts of biological, psychological and social space and time.
In living matter, space and time characterize the peculiarities of the spatiotemporal parameters of organic matter: the biological existence of the human individual, the change in species of plant and animal organisms.
Space, in which life phenomena occur, i.e. there are living organisms and manifestations of their aggregates, is enantiomorphic space. Those. its vectors are polar and enantiomorphic. Without this there could be no dissymmetry in living organisms.
In the geometric expression of time in which life phenomena occur, all its vectors must also be polar and enantiomorphic.
Biological time is called, associated with life phenomena and corresponding to the space of living organisms, which has dissymmetry.
Time polarity in biological phenomena is expressed in the fact that these processes are irreversible, i.e. geometrically, in the line A→B, the vectors AB and BA are different.
Enantiomorphy of time is expressed in the fact that in a process that occurs over time, dissymmetry naturally appears at certain intervals.
The properties and manifestation of such time associated with space are sharply different from the rest of the space on our planet, and may differ from other times. This question can only be resolved by empirical study of time.
Such a study shows that biological time is equal in duration to geological time, since throughout geological history we are dealing with life. Biological time covers about n∙10 9 years, n = 1.5÷3.
The beginning of life, i.e. We do not know the beginning of biological time, and there is no data on the end of biological time. This biological time manifested itself in the same environment, because all living things came from living things. It was an irreversible process, where time related to space has polar vectors. This is indicated by a single process of evolution of species. moving steadily in the same direction all the time. It goes at different speeds for different species, with stops, but in general the picture of wildlife is constantly changing, without stopping or turning back. It is typical for some species to become extinct, i.e. pronounced polar nature of time vectors. The question of the existence of a certain time limit for plant and animal species has been raised more than once, but, apparently, in general form it should be resolved negatively, since there are species that invariably exist without significant morphological changes for hundreds of millions of years. The most characteristic thing, in the sense of time in living matter, is the existence of generations.
Generations, genetically alternating, constantly change in their morphological characteristics, and this change either occurs in jumps over large periods of time, or, conversely, accumulates imperceptibly from generation to generation. becoming visible only after large numbers of generations. It is important that in both cases there is an irreversible process that occurs over time.
In biological science, a prominent place is occupied by questions of the temporal organization of living systems, and this applies to all biological levels of existence. Everyone understands that every biological process has a temporal character. But simply stating this fact does not help much. It is much more urgent to decide on the concept of biological time1, without which, as is obvious, it is impossible to build a biological theory. In this regard, we have to look for answers to a number of difficult questions. What is time? Does biological time exist? Is biological time different from physical time? Is time related to different levels of biological existence identical? How is biological time measured?
Time is the duration (b) of some processes. The durations of physical processes (tf) form physical time. The duration of biological processes (tb) is precisely biological time. It seems obvious that biological time is different from physical time. But already at this stage of analysis a surprise awaits us. Many authors believe that the units of measurement of physical and biological time are the same, for example, seconds. If it is true. then there is an obvious paradox: qualitatively different phenomena should not be measured in the same units.
Faced with the above paradox, it is reasonable to think about the nature of durations. Strictly speaking, duration is an elementary feature of processes, which means that it cannot be determined on the basis of other features. But duration can well be compared with other characteristics of objects. Having done this, it is not difficult to find out that duration is an integral characteristic of an irreversible process. The more part of its history an object has passed through, the longer its duration (age). If the researcher is interested in a more detailed description of the process, then he considers differential
in differential-time form. As we see, the concept of time plays an extremely important role in the formulation of procedural laws. But what time should be in the denominator? There is no answer to this question yet. Our characterization of the phenomenon of time is still superficial. It is extremely important to understand exactly how the concept of time was refined in biology.
Karl Baer was one of the first to recognize the problem of biological time. “The inner life of a person or an animal,” he noted, “can proceed faster or slower in a given space of time... this inner life is the main measure by which we measure time when contemplating nature.”1 It is probably more correct to say: that biological time is a measure of the life of a person or animal. If only we knew what exactly this measure consists of. In this regard, it is reasonable to listen to V.I. Vernadsky. Characterizing biological time, he noted that “for each form of organisms there is a natural frailty its manifestations: a certain average lifespan of an individual indivisible, each form has its own rhythmic change of generations, the irreversibility of the process.
For life, time... is expressed in three different processes: firstly, the time of individual existence, secondly, the time of change of generations without changing the form of life and, thirdly, evolutionary time - changes of forms, simultaneous with the change of generations.” It is easy to see that indicated by V.I. Vernadsky, the features of the frailty of organisms in principle do not contradict the traditional calculation of the calendar
time in the usual seconds, minutes, hours and days. But it is unlikely that calendar time is both a physical and biological phenomenon.
A certain clarification of the concept of biological time is promised by the doctrine of biorhythms, which are studied widely and multifacetedly. In biorhythms, the temporal organization, orderliness of biological phenomena, as well as their adaptation to external conditions find their most complete expression. In its most traditional interpretation, biorhythmology is associated only with calendar durations. Therefore, within its framework, the question of special units of measurement of biological time usually does not receive any significant development. But the situation changes dramatically when biorhythmology is complemented by the concept of the so-called biological clock. “In every cell of animals or plants,” notes S.E. Shnol, - there are genes that determine the circadian periodicity of life. Intracellular “clocks” adjust their course to the periods of day and night - light and dark - and are little dependent on temperature changes. In the central nervous system of animals there are the main “clocks” that control the clocks of other cells.”1 Within the framework of the concept of biorhythms, it is reasonable to consider the duration of one rhythm as a unit of time. Calendar durations of rhythms vary within certain limits, but all rhythmic units are identical to each other. Apparently, for the first time before The true concept of biological time has dawned on us, but let us continue our efforts to comprehend it.
As noted by A. A. Detlaf and T. A. Detlaf, who fruitfully studied the problem of biological time for a quarter of a century, “biologists have repeatedly faced the task of finding a unit of biological time that would be comparable in one species of animal under different conditions, as well as in different types of animals. Some researchers have proposed several particular solutions to this problem. Moreover, in all cases, time was defined not in units of astronomical time, but in fractions (or number) of a particular period of development, the duration of which was taken as a unit of time.” They themselves came to the conclusion that in embryology
“The duration of any period of embryonic development can serve as a measure of time.”
The point of view according to which the unit of biological time is the duration of some physical and chemical process of biological significance is extremely widespread in modern literature. It is found in almost every publication devoted to the problem of biological time. Indicative, for example, is the statement of N.V. Timofeev-Resovsky: “Evolutionary time is determined not by astronomical time, not by clocks, but by generations, i.e. time of generational change."
In our opinion, the concept of biological time under consideration is flawed. Its content is a straightforward transition from physical time to biological time. Essentially, it is stated that
But this formula is obviously incorrect, because the left and right sides contain values of different dimensions. Physical time is measured in seconds, and biological time is measured in special biological units, which are proposed to be called, for example, Darwins or Mendels. There may indeed be a connection between physical and biological time, but according to the formula
where kbph is the dimensional proportionality coefficient, which fixes the ratio of physical and biological units.
Gaston Backman tried to install it. He even came to the conclusion that there is a relatively simple logarithmic relationship between physical and biological time in ontogenesis. But the latest data do not confirm this conclusion. At least, it does not have the degree of universality that Backman assumed. The kbph coefficient is not a constant value, but a “floating” function. In relation to different levels of being, it is expressed by various, and far from simple, functions.
The biological clock concept is unsatisfactory in another respect. We mean that the problem of duration congruence was not adequately addressed in it. Two long-
ties are congruent if the processes of which they are measures are equivalent. Let's say we are considering a physical process whose duration is 10 s. In this case, for example, the second second is congruent to the eighth or any other. In physics, it is not the case that any periodic process is recognized as a clock. A physical clock is only the process that ensures that the congruence condition is met.
It seems to us that the condition of congruence is relevant not only for physics, but also for biology. Let us illustrate this with a simple example. We will assume that a certain biological state is achieved through n cell divisions. Is it always acceptable to consider these divisions congruent to each other? The answer is negative, because the significance of these divisions may be different; it is possible that, for example, the fifth division is the most important. But this means that the calendar duration of one division cannot be considered a unit of time. All units of time must be congruent with each other. But in the considered case this requirement is not met. As a biological clock, it is advisable to choose only that periodic process that fulfills the congruence condition. Of course, having turned to the congruence condition, the researcher will have to engage in thorough theoretical reflection.
Above, we have repeatedly drawn attention to the need for a clear distinction between the concepts of physical and biological duration. In this regard, let us consider them in the context of supervenience and symbolic connection. At the supervenience stage, the researcher deals only with physical time. At the symbolization stage, physical time is seen as a symbol of biological time. We can say that we are talking about the biological relativity of physical time. It is this that often comes to the attention of researchers who are guided by the relation = Дtb.. In our opinion, they
do not clearly express the specificity and independence of biological time. If this does not take place, then biological time is reduced to physical time.
But does biological time exist as such? Maybe it’s enough to talk about the biological relativity of physical time? These questions, which are key to the problem of biological time, are not discussed by the vast majority of researchers at all. In our opinion, biological time really exists. Few people doubt the reality of biological processes. But there are no atemporal processes. Physical time is not
is an adequate characteristic of biological processes. This characteristic is biological time. Let us assume that we are considering a number of sequential states of some biological object: Do, D\, D2, Ac, where Do is the initial state, and Ac is the final state. If a researcher wants to know how far an object has moved from its initial state towards its final state, then he has no other way than to use the biological duration parameter. For example, the time measure of state Dii is At%. Researchers who doubt the reality of biological time can with the same reason doubt the reality of biological processes.
The multilevel nature of biological processes is accompanied by the multilevel nature of biological time. Emphasizing this fact has become common place. A biological object combines different biological times. We can say that he is between the blades of time. If one of the organs has exhausted its temporary resource, then the death of the individual occurs. The phenomenon of life presupposes the harmony of many forms of biological time.
Let's move on to the final topic of this paragraph, perhaps the most relevant. There are many ideals in science, but perhaps the most important is the ideal of the differential law. This law describes the successive stages of some process through a differential equation. Ideally the form should be used
In reality, the form used is
reflects the specifics of a biological process. Detailed analysis shows that biological analysis involves many steps. Ultimately, the phenomenon of biological time also finds its understanding. In our opinion, as biological knowledge develops, appeal to it will become more and more obvious.
It has long been noted that all life on Earth obeys certain rhythms that are set by global processes. This is the daily rotation of the planet around its axis and its movement along the solar orbit. Living organisms somehow sense time, and their behavior is subject to its flow. This is manifested in the alternation of periods of activity and sleep in animals, in the opening and closing of flowers in plants. Every spring, migratory birds return to their nesting sites, hatch their chicks, and migrate to warmer regions for the winter.
What is a biological clock?
The rhythmicity of all life processes is a property inherent in all inhabitants of our planet. For example, marine unicellular flagellates glow at night. It is unknown why they do this. But during the day they do not glow. Flagellates acquired this property during the process of evolution.
Every living organism on Earth - both plants and animals - has an internal clock. They determine the frequency of life activity, tied to the length of the earth’s day. This biological clock adapts its course to the frequency of day and night; it does not depend on temperature changes. In addition to daily cycles, there are seasonal (annual) and lunar periods.
Biological clock is to some extent a conventional concept, implying the ability of living organisms to navigate in time. This property is inherent in them at the genetic level and is inherited.
Studying the mechanism of the biological clock
For a long time, the rhythmicity of the life processes of living organisms was explained by the rhythmicity of changes in environmental conditions: illumination, humidity, temperature, atmospheric pressure and even the intensity of cosmic radiation. However, simple experiments have shown that the biological clock works regardless of changes in external conditions.
Today it is known that they are present in every cell. In complex organisms, clocks form a complex hierarchical system. This is necessary to function as a whole. If any organs and tissues are not coordinated in time, various types of diseases arise. The internal clock is endogenous, that is, it has an internal nature and is adjusted by signals from the outside. What else do we know?
Biological clocks are inherited. In recent years, evidence of this fact has been found. Cells have clock genes. They are subject to mutations and natural selection. This is necessary to coordinate life processes with the daily rotation of the Earth. Since at different latitudes the ratios of day and night lengths are not the same throughout the year, clocks are also needed to adapt to the changing seasons. They must consider whether day and night increase or decrease. There is no other way to distinguish between spring and autumn.
By studying the biological clocks of plants, scientists have discovered the mechanism by which they adapt to changes in day length. This occurs with the participation of special phytochrome regulators. How does this mechanism work? The phytochrome enzyme exists in two forms, which change from one to the other depending on the time of day. The result is a clock regulated by external signals. All processes in plants - growth, flowering - depend on the concentration of the phytochrome enzyme.
The mechanism of the intracellular clock has not yet been fully studied, but most of the way has been covered.
Circadian rhythms in the human body
Periodic changes in the intensity of biological processes are associated with the alternation of day and night. These rhythms are called circadian, or circadian. Their frequency is about 24 hours. Although circadian rhythms are associated with processes occurring outside the body, they are of endogenous origin.
A person does not have organs or physiological functions that do not obey daily cycles. Today there are more than 300 known.
The human biological clock regulates the following processes in accordance with circadian rhythms:
Heart rate and breathing rate;
The body's consumption of oxygen;
Intestinal peristalsis;
The intensity of the glands;
Alternation of sleep and rest.
These are just the main manifestations.
The rhythm of physiological functions occurs at all levels - from changes within the cell to reactions at the level of the body. Experiments in recent years have shown that circadian rhythms are based on endogenous, self-sustaining processes. The human biological clock is set to oscillate every 24 hours. They are associated with changes in the environment. The ticking of the biological clock is synchronized with some of these changes. The most characteristic of them are the alternation of day and night and daily temperature fluctuations.
It is believed that in higher organisms the main clock is located in the brain in the suprachiasmatic nucleus of the thalamus. Nerve fibers from the optic nerve lead to it, and the hormone melatonin, produced by the pineal gland, is brought with the blood, among others. This is an organ that was once the third eye of ancient reptiles and retained the functions of regulating circadian rhythms.
Biological clock of organs
All physiological processes in the human body occur in a certain cycle. Temperature, pressure, and blood sugar concentration change.
Human organs are subject to a circadian rhythm. Over the course of 24 hours, their functions alternate between periods of rise and fall. That is, always, at the same time, for 2 hours the organ works especially efficiently, after which it enters the relaxation phase. At this time, the organ rests and recovers. This phase also lasts 2 hours.
For example, the phase of rising gastric activity occurs from 7 to 9 hours, followed by a decline, from 9 to 11. The spleen and pancreas are active from 9 to 11, and rest from 11 to 13. For the heart, these periods occur at 11-13 hours and 13-15. The bladder has an active phase from 15 to 17, rest and rest - from 17 to 19.
The biological clock of organs is one of those mechanisms that has allowed the inhabitants of the Earth to adapt to the circadian rhythm over millions of years of evolution. But man-made civilization is steadily destroying this rhythm. Research shows that it’s easy to unbalance the body’s biological clock. It is enough just to radically change your diet. For example, start having dinner in the middle of the night. Therefore, a strict diet is a fundamental principle. It is especially important to observe it from early childhood, when the biological clock of the human body “winds up”. Life expectancy directly depends on this.
Chronogerontology
This is a new, recently emerged scientific discipline that studies age-related changes in biological rhythms that occur in the human body. Chronogerontology arose at the intersection of two sciences - chronobiology and gerontology.
One of the subjects of research is the mechanism of functioning of the so-called “large biological clock”. This term was first introduced into circulation by the outstanding scientist V. M. Dilman.
“Large biological clock” is a rather relative concept. It is, rather, a model of the aging processes occurring in the body. It gives an understanding of the relationship between a person’s lifestyle, his food preferences and his actual biological age. This clock keeps track of life expectancy. They record the accumulation of changes in the human body from birth to death.
The course of the large biological clock is uneven. They are either in a hurry or lagging behind. Their progress is influenced by many factors. They either shorten or lengthen life.
The principle of operation of large biological clocks is that they do not measure periods of time. They measure the rhythm of processes, or more precisely, the loss of it with age.
Research in this direction can help solve the main problem of medicine - the elimination of diseases of aging, which today are the main obstacle to reaching the species limit of human life. Now this figure is estimated at 120 years.
Dream
The internal rhythms of the body regulate all vital processes. The time of falling asleep and waking up, the duration of sleep - the “third eye” - the thalamus - is responsible for everything. It has been proven that this part of the brain is responsible for the production of melatonin, a hormone that regulates human biorhythms. Its level is subject to daily rhythms and is regulated by illumination of the retina. With changes in light intensity, melatonin levels increase or decrease.
The sleep mechanism is very delicate and vulnerable. Disruption of the alternation of sleep and wakefulness, which is inherent in humans by nature, causes serious harm to health. Thus, constant shift work that involves working at night is associated with a higher likelihood of diseases such as type 2 diabetes, heart attacks and cancer.
In sleep, a person completely relaxes. All organs rest, only the brain continues to work, systematizing the information received during the day.
Reduced sleep duration
Civilization makes its own adjustments to life. By studying the biological sleep clock, scientists discovered that modern people sleep 1.5 hours less than people in the 19th century. Why is reducing the time of night rest dangerous?
Disruption of the natural rhythm of alternating sleep and wakefulness leads to malfunctions and disruptions in the functioning of the vital systems of the human body: immune, cardiovascular, endocrine. Lack of sleep leads to excess body weight and affects vision. A person begins to feel discomfort in the eyes, the clarity of the image is impaired, and there is a danger of developing a serious disease - glaucoma.
Lack of sleep provokes disruptions in the functioning of the human endocrine system, thereby increasing the risk of developing a serious illness - diabetes.
Researchers have discovered an interesting pattern: life expectancy is longer in people who sleep from 6.5 to 7.5 hours. Both reduction and increase in sleep time lead to a decrease in life expectancy.
Biological clock and women's health
Many studies have been devoted to this problem. A woman's biological clock is her body's ability to produce offspring. There is another term - fertility. We are talking about the age limit favorable for having children.
A few decades ago, the clock showed the thirty-year mark. It was believed that realizing oneself as mothers for the fair sex after this age was associated with a risk to the health of the woman and her unborn child.
Now the situation has changed. The number of women who conceived a child for the first time between the ages of 30 and 39 increased significantly - 2.5 times - and those who did so after 40 increased by 50%.
Nevertheless, experts consider 20-24 years to be a favorable age for motherhood. Often the desire to get an education and realize oneself in the professional field wins. Only a few women take responsibility for raising a child at this age. Puberty is 10 years ahead of emotional maturity. Therefore, most experts are inclined to believe that for a modern woman the optimal time to give birth to a child is 35 years. Today they are no longer included in the so-called risk group.
Biological clock and medicine
The human body's response to various influences depends on the phase of the circadian rhythm. Therefore, biological rhythms play an important role in medicine, especially in the diagnosis and treatment of many diseases. Thus, the effect of medications depends on the phase of the circadian biorhythm. For example, when treating teeth, the analgesic effect is maximal from 12 to 18 hours.
Chronopharmacology studies changes in the sensitivity of the human body to drugs. Based on information about daily biorhythms, the most effective drug regimens are developed.
For example, purely individual fluctuations in blood pressure require consideration of this factor when taking medications for the treatment of hypertension and ischemia. So, in order to avoid a crisis, people at risk should take medications in the evening, when the body is most vulnerable.
In addition to the fact that the biorhythms of the human body influence the effect of taking drugs, rhythm disturbances can cause various diseases. They belong to the so-called dynamic ailments.
Desynchronosis and its prevention
Daylight is of great importance for human health. It is sunlight that provides natural synchronization of biorhythms. If the lighting is insufficient, as happens in winter, a failure occurs. This can be the cause of many diseases. Mental (depressive states) and physical (decreased general immunity, weakness, etc.) develop. The cause of these disorders lies in desynchronosis.
Desynchronosis occurs when the human body's biological clock malfunctions. The reasons may be different. Desynchronosis occurs when changing time zones for a long period, during the adaptation period during the transition to winter (summer) time, during shift work, addiction to alcohol, and disordered eating. This is expressed in sleep disorders, migraine attacks, decreased attention and concentration. As a result, apathy and depression may occur. For older people, adaptation is more difficult and it takes them longer.
To prevent desynchronosis and correct body rhythms, substances are used that can affect the phases of biological rhythms. They are called chronobiotics. They are found in medicinal plants.
The biological clock lends itself well to correction with the help of music. It helps to increase labor productivity when performing monotonous work. Sleep disorders and neuropsychiatric diseases are also treated with the help of music.
Rhythm in everything is the way to improve the quality of life.
Practical significance of biorhythmology
The biological clock is the subject of serious scientific research. Their customers include many sectors of the economy. The results of studying the biological rhythms of living organisms are successfully applied in practice.
Knowledge of the rhythms of life of domestic animals and cultivated plants helps to increase the efficiency of agricultural production. Hunters and fishermen use this knowledge.
Medical science takes into account daily fluctuations in physiological processes in the body. The effectiveness of taking medications, surgical interventions, performing medical procedures and manipulations directly depends on the biological clock of organs and systems.
The achievements of biorhythmology have long been used in organizing the work and rest regime of airliner crews. Their work involves crossing several time zones in one flight. Eliminating the adverse effects of this factor is very important for maintaining the health of airline flight personnel.
It is difficult to do without the achievements of biorhythmology in space medicine, especially when preparing for long flights. Far-reaching grandiose plans to create human settlements on Mars will apparently not be possible without studying the peculiarities of the functioning of the human biological clock in the conditions of this planet.