In connection with the socialization of man, his biological role is gradually losing its significance. This happens not because people have reached the highest levels of development, but because of the conscious distance from their actual “foundation” (biosphere), which gave a person the opportunity to develop and build a modern society. But the organism as a biological system cannot exist outside the biosphere, and therefore should be considered only together with it.
Population and society
Any society is a self-regulated population, a modern analogue of a reasonable biological system (BS) within the biosphere. And a person is, first of all, a product of the evolution of the BS, and not the result of the development of a social society, which is secondary. Strictly speaking, society is a particular examplepopulation, which is also a BS, located only one level above a living organism.
From the point of view of biology, this term characterizes a system of organs and tissues built into the living shell of the planet, which has its own mechanisms of influence on habitats and protective reactions. Considering the body as a biological system, it is easy to identify the main mechanisms of its life, adaptation and regulation of its functions. And within the framework of this publication, the human body will be considered as an integral system in terms of its criteria.
Terminology
System is a large collection of some interdependent elements that form a certain integrity (structure) that has undergone a long evolution in the course of its formation.
Biological systems are indivisible sets of interconnected elements that create the living shell of the planet and are part of it, playing a critical role in its existence. Examples of biological systems: cell, organism, macromolecules, organelles, tissues, organs, populations.
An organism is a complexly organized independently regulated and actively functioning system, consisting of organs and tissues or represented by one biological system, forming one object of wildlife. The organism actively interacts with biological systems of a higher order (with the population and the biosphere).
Regulation is ordering, obedience to strict rules, creating conditions for their implementation and control. In the context of the human organism, the term should be considered as a processnormalization of organismic functions.
Universal structure
To consider the human body as a biological system (BS), its main properties should be identified and correlated. So, the main property of BS is their structure: they all consist of organic molecules and biopolymers. It is noteworthy that the BS also includes inorganic substances, which are attributes of inanimate nature. However, they are not formative for a biological molecule, organelle, cell or organism, but are only built into these systems.
Orderedness
A high degree of order is the second property of systems. The so-called hierarchy is very important for the functioning of the biosphere for the reason that its entire structure is built on the principle of complicating the simple and combining the elementary. That is, the more complex components of the living shell of the earth (biological systems) consist of smaller ones located lower in the hierarchy.
A particular example is the evolution of life from a macromolecule to an organic polymer, and then to an organelle and subcellular structure, from which tissue, an organ, and an organism are later formed. As an integral biological system, such a hierarchical structure allows you to form all levels of wildlife and track the interaction between them.
Integrity and discreteness
One of the most important properties of any BS is its simultaneous integrity and discreteness (partiality, componentiality). This means that any livingan organism is a biological system, an integral set formed from autonomous components. The autonomous components themselves are also living systems, just lower in the hierarchy. They can exist autonomously, but within the body they obey its regulatory mechanisms and form an integral structure.
Examples of simultaneous integrity and discreteness can be found in any systems of different levels. For example, the cytoplasmic membrane as an integral structure has hydrophobicity and lipophilicity, fluidity and selective permeability. It consists of macromolecules of lipoproteins, which provide only lipophilicity and hydrophobicity, and of glycoproteins, which are responsible for selective permeability.
This is a demonstration of how the set of discrete properties of the components of a biological system provides the functions of a more complex higher structure. An example is also an integral organelle, consisting of a membrane and a group of enzymes, which inherited their discrete qualities. Or a cell that is able to realize all the functions of its constituent components (organelles). The human body as a single biological system is also subject to such dependence, as it demonstrates common qualities that are private for discrete elements.
Energy Exchange
This property of a biological system is also universal and can be traced at each of its hierarchical levels, starting from the macromolecule and ending with the biosphere. At each specific level,has various manifestations. For example, at the level of macromolecules and precellular structures, energy exchange means a change in the spatial structure and electron density under the influence of pH, electric field, or temperature. At the cell level, energy exchange should be considered as metabolism, a set of processes of cellular respiration, oxidation of fats and carbohydrates, synthesis and storage of macroergic compounds, removal of metabolic products outside the cell.
Body metabolism
The human body, as a biological system, also exchanges energy with the outside world and transforms it. For example, the energy of chemical bonds of carbohydrate and fat molecules is effectively used in the cells of the body for the synthesis of macroergs, from which it is easier for organelles to extract energy for their life activity. In this demonstration, the transformation of energy and its accumulation in macroergs, as well as the implementation by hydrolysis of the phosphate chemical bonds of ATP.
Self-regulation
This characteristic of biological systems means the ability to increase or decrease its functional activity depending on the achievement of any states. For example, if a bacterial cell experiences starvation, then it either moves towards a food source, or forms a spore (a form that will allow it to maintain vital activity until living conditions improve). In short, the body as a biological system has a complex multi-level system of regulation of its functions. She isconsists of:
- precellular (regulation of the functions of individual cell organelles, for example, ribosomes, nuclei, lysosomes, mitochondria);
- cellular (regulation of cell functions depending on external and internal factors);
- tissue regulation (control of the growth rate and reproduction of tissue cells under the influence of external factors);
- organ regulation (formation of mechanisms for activation and inhibition of the functions of individual organs);
- systemic (nervous or humoral regulation of functions by higher organs).
The human body as a self-regulating biological system has two main regulatory mechanisms. This is an evolutionary older humoral mechanism and a more modern nervous one. These are multi-level complexes capable of regulating the metabolic rate, temperature, pH of biological fluids and homeostasis, the ability to defend against dangers or provide aggression, realize emotions and higher nervous activity.
Levels of humoral regulation
Humoral regulation is the process of accelerating (or slowing down) biological processes in organelles, cells, tissues or organs under the influence of chemicals. And depending on the location of their "target", they distinguish cellular, local (tissue), organ and organismal regulation. An example of cellular regulation is the influence of the nucleus on the rate of protein biosynthesis.
Tissue regulation is the release of chemicals (local mediators) by the cell, aimed atsuppression or enhancement of the functions of surrounding cells. For example, a cell population experiencing oxygen starvation releases angiogenesis factors that cause the growth of blood vessels towards them (depleted areas). Another example of tissue regulation is the release of substances (keylons) that can suppress the rate of cell reproduction in a certain place.
This mechanism, unlike the previous one, is an example of negative feedback. It is characterized as an active action of the cell population, designed to suppress any process in the biological tissue.
Higher humoral regulation
The human body as a single self-developing biological system is an evolutionary crown that has realized the highest humoral regulation. It became possible due to the development of endocrine glands capable of secreting hormonal substances. Hormones are specific chemicals that are secreted by the endocrine glands directly into the blood and act on target organs located at a great distance from the place of synthesis.
Higher humoral regulation is also a hierarchical system, the main organ of which is the pituitary gland. Its functions are regulated by a neurological structure (hypothalamus), located above the others in the body's regulatory hierarchy. Under the influence of nerve impulses of the hypothalamus, the pituitary gland secretes three groups of hormones. They enter the bloodstream and are carried by it to target organs.
In the tropic hormones of the pituitary gland, the target is the lower hormonal gland, which, under the influence of these substances, releases its mediators that directly affect the functions of organs and tissues.
Nervous regulation
Regulation of the functions of the human body is mainly realized through the nervous system. It also controls the humoral system, making it, as it were, its own structural component, capable of more flexibly influencing the body's functions. At the same time, the nervous system is also multilevel. In humans, it has the most complex development, although it continues to improve and change extremely slowly.
At this stage, it is characterized by the presence of functions responsible for higher nervous activity: memory, attention, emotionality, intelligence. And, perhaps, one of the main properties of the nervous system is the ability to work with analyzers: visual, auditory, olfactory, and others. It allows you to remember their signals, reproduce them in memory and synthesize new information based on them, also forming sensory experience at the level of the limbic system.
Nervous regulation levels
The human body as a single biological system has several levels of nervous regulation. It is more convenient to consider them according to the gradation scheme from the lowest levels to the highest. Below the rest is the autonomic (sympathetic and parasympathetic) nervous system, which regulates its functions independently of the higher centers of nervous activity.
It functions due to the nucleus of the vagus nerve and the adrenal medulla. It is noteworthy that the lowest level of nervous regulation is located as close as possible to the humoral system. This again demonstrates the simultaneous discreteness and integrity of the organism as a biological system. Strictly speaking, the nervous system transmits its signals under the influence of acetylcholine and electric current. That is, it consists of half the humoral information transmission system, which is observed in synapses.
Higher nervous activity
Above the autonomic nervous system is the somatic system, which consists of the spinal cord, nerves, brainstem, white and gray matter of the brain, its basal ganglia, limbic system and other important structures. It is she who is responsible for higher nervous activity, work with analyzers of the sense organs, systematization of information in the cortex, its synthesis and the development of speech communication. Ultimately, it is this complex of biological structures of the body that is responsible for the possible socialization of a person and the achievement of his current level of development. But without low-level structures, their appearance would be impossible, as well as the existence of a person outside the usual habitat.
