Chapter 1. The body is a repository of the spirit
The mind is gifted and the thought is rich,
A repository of the spirit and mind he,
And the wordless world is under his command.
The General principles of the structure
The personality of man is concentrated in his living material body. Outside the body, the individual cannot function as a person.
How does a man’s body work? The body is complete, otherwise it can not exist, but it is built on a hierarchical principle. There are several levels: cellular, tissue, organ, systemic, single organism.
I’ll start with the cells.
The cell is the basic structural and functional unit of the structure of the living. One single cell forms the body of amoeba, about 220 billion cells-the human body. Imagine something incredible-someone managed to disassemble it into separate cells and put it in a continuous row. The length of this series will reach almost 15 000 km.
The chemical composition of the cell. D. I. Mendeleev’s periodic chemical system today has 109 elements, of which more than 100 are part of the cell. Four of them (oxygen, carbon, hydrogen and nitrogen) make up about 98% of the cell mass. The rest are divided into macronutrients (calcium, phosphorus, potassium, sodium, sulfur, chlorine, magnesium), trace elements (iron, zinc, fluorine, copper, iodine, etc.) and ultramicroelements (selenium, cobalt, chromium, etc.). All of them are involved in metabolism. The cell is dominated by water, in the human body its relative amount reaches 70-80 %. Water-an inorganic substance, it is a universal solvent, water-the main actor in metabolism and heat regulation. About water we will tell in detail in Chapter 2.
Organic substances in the cell are proteins, fats, carbohydrates and nucleic acids. Protein molecule is a complex structure formed from one or more polypeptide chains – amino acids, which are interconnected by peptide bonds. Proteins play a very important role in the life of the body: they are part of all the muscles, tissues, organs and other structures, taking part in the regulation of their functions, and performing the role of enzymes and hormones in the body. Proteins are synthesized in cells from amino acids, which are formed as a result of digestion of proteins entering the body from food.
Fats – esters of fatty acids and any alcohol (eg, triglycerides), the main form of energy storage in the body (in adipose tissue).
Carbohydrates-representatives of a large group of compounds, which include carbon, hydrogen and oxygen. Carbohydrates (monosaccharides, oligosaccharides, polysaccharides) are an important source of energy, they are produced by plants and enter the body of animals and humans with food. Carbohydrates eventually break down in the body to a simple sugar glucose, which then takes part in the metabolic processes that occur with the release of energy (glucose is the main source of energy in many cells). Vegetable carbohydrates are an important building material (e.g. cellulose) as well as a depot of finished products (mainly starch).
Nucleic acids – the main molecules of life – DNA or RNA, which are present in the nuclei, and RNA and the cytoplasm of all living cells (Fig. 1.1). Their main functions are storage and transmission of hereditary (biological) information and participation in protein synthesis. DNA consists of two polynucleotide chains. These chains are twisted around each other, forming a double helix, and are joined together by hydrogen bonds between the nucleotide bases like stairs. Genetic information in DNA molecules is contained in a sequence of bases located along the molecule. A DNA molecule can replicate itself during replication, thus transmitting genetic information to daughter cells during cell division.
- Note. DNA in the sequence of bases contains genetic information that determines the specificity of proteins synthesized by the cell, i.e. the sequence of amino acids in the protein chain.
- Gene (from Greek. genos-genus, origin) – an elementary structural and functional unit of heredity, represented by a portion of the DNA molecule with a strictly defined sequence of nucleotides, responsible for the synthesis of a single protein.
- RNA molecule is a single polynucleotide chain formed by nucleotides. This acid is involved in the synthesis of proteins in the cell.
Each cell is limited by a cell membrane that performs many functions: transport (the flow of various substances into the cell and the removal of waste products from it), protective, signal perception. The structure of the cell includes the cytoplasm, it is the nucleus, which stores the genetic (hereditary) material, and organelles that perform specific functions. These include, for example, the mitochondria – the “power plant” of the cell; ribosomes engaged in protein synthesis; endoplasmic reticulum, which synthesizes various substances; Golgi apparatus, where accumulated, Packed, transported within the cell and removed from the cell synthesized products; lysosomes, carrying out the splitting of substances in the cell; cell skeleton, performing a support function in the cell, etc.
The nucleus is the basic structure of a cell containing its genetic material – deoxyribonucleic acid (DNA). DNA, combined with a protein, usually scattered through the nucleus in the form of chromatin. During cell division, chromatin spirals and becomes visually distinguishable in the form of chromosomes. The composition of the nucleus also includes ribonucleic acid (RNA), most of which is concentrated in the nucleolus. Chromatin and nucleolus are in the nucleoplasm. The nucleus is separated from the cytoplasm by a double membrane – a nuclear envelope.
Pay attention! The chromatin of the nucleus undivided and the chromosome dividing is essentially the same.
Chromosome consists of two long polynucleotide chains that form the DNA molecule. The chains are spirally twisted around one another. DNA is linked to histone proteins. Along the entire length of the DNA molecule linearly arranged genes. Chromosomes are well dyed in the process of cell division. In the human body, there are two types of cells, fundamentally different from each other: sexual and somatic, or bodily (from Greek. soma-body). The nucleus of each somatic human cell contains 46 chromosomes, 23 of them are maternal, and 23 – paternal, in other words, in the somatic cell there are two copies of each chromosome, they are called homologous. They are the same in length, shape, structure, location of the bands and carry the same genes that are localized equally. In each pair of chromosomes, one comes from the nucleus of the sperm, the other – from the nucleus of the egg. Only sex chromosomes are an exception. The male (Y) chromosome is very different from the female (X) chromosome. The Y chromosome is much smaller than the X chromosome and other chromosomes. Normal karyotype (from Greek. karyon-nut kernel, typos-sample) of human somatic cells includes 23 pairs of chromosomes( diploid set), 22 pairs of autosomes and one pair of sex chromosomes (XX in women or XY in men); sex cells contain haploid (single) set-23 chromosomes: 22 autosomes and one sex.
Each chromosome can reproduce its exact copy in the intervals between cell divisions, so that each new cell is formed receives a complete set of chromosomes. Cells are reproduced only by cell division. The growth of the body, recovery from damage, the formation of new cells, an increase in their number is due to cell division.
There are two types of cell division: mitosis and meiosis. Mitosis is a type of cell division, in which two genetically identical daughter cells are formed from one cell, and each of them, like the mother, has 23 pairs of chromosomes (46 pieces). During mitosis, the formation of new cells in the process of growth and regeneration (recovery).
In humans and other animals, sexually reproducing, constantly alternate two generations of cells: somatic, having 46 chromosomes, and sexual, having 23 chromosomes. Meiosis is a type of cell division in which four daughter cells are formed from one mother cell, each of which has half of the chromosomal set of the somatic cell, i.e. 23 chromosomes. As a result of this division, sperm and eggs are formed, and after fertilization, a normal (diploid) set of chromosomes is restored (23 chromosomes of the sperm + 23 chromosomes of the egg = 46 chromosomes of the new organism). During meiosis, certain genetic changes occur in daughter cells.
All eggs contain the sex chromosome X, part of the sperm-sex chromosome X, the other part-Y. If the egg fertilizes sperm X, the girl is born (sex chromosomes XX), if the sperm Y – boy (sex chromosomes XY).
Cells and their derivatives form four types of tissues: epithelial, connective, muscular and nervous. Tissues form organs.
The organ is characterized by its inherent form and structure, best adapted to perform a specific function, for example, the heart, lung. Organs contain all types of tissues, but one of them is the main, “working”, it implements the main function: for example, in the liver, lungs, kidneys, glands is epithelial tissue, in muscles – muscle, in the brain – nervous.
The organs are anatomically and functionally combined into organ systems. System-a number of organs that have a common structure plan, unity of origin and perform one big function (for example, digestion, breathing). In the human body identify the following organ systems: digestive (digestive), respiratory (breathing), mochevydelitelnoj, reproductive, nervous, cardiovascular, lymphatic (immune, organs of hematopoiesis and immune systems), senses (touch system). Some organs are United on a functional basis in the apparatus: they often have a different structure and origin, may not be anatomically related, but they are United or participate in the performance of a common function (eg, musculoskeletal, endocrine apparatus), or these organs are different in their functional tasks, but are connected by a single origin (genitourinary apparatus).
All men belong to the same species and have the same principles of body structure, but a lot of significant and sometimes minor features makes each unique.
During the first seven years of life, sexual differences, except for primary sexual characteristics (genitals), are almost not expressed. In the second childhood period (8 – 12) begins, perhaps, the most important event in the life of the men puberty. At this time, rapidly growing testicles, penis and larynx. Growth progresses in adolescence (13-16 years). Begin to grow hair on the face and pubis on the male type, there is the formation of the voice (secondary sexual characteristics), pigmented skin of the scrotum, there are the first ejaculation. These changes are associated with the increasing production of the testicles of the male sex hormone testosterone. These hormones are very important for the formation and maintenance of masculinity. Masculinity (from lat. masculinus male) – the human condition, the structure of the body which and behaviours characteristic of men. In adolescence (17-21 years) completed the growth, development and puberty of men. In the first period of adulthood (22-35 years) begins an active sex life and professional activities that develop and become more complex. In the second period of adulthood (36-60 years) a man reaches the heights of his personal and professional life.
Today, at the beginning of the XXI century more and more attention of doctors, psychologists, sociologists attracts the second period of adulthood. One of the authors of this book has more than 10 years ago proposed to expand the time limits of Mature age men. The first period-22-50 years, the second (average age) period – 51-75 years. This is the period of greatest opportunities, when a man has gained a lot of life experience, professional knowledge and skills. At this time, there are serious changes in the consciousness of men, no less (and sometimes more important) than during puberty. Many reduced the production of male sex hormone, reduced sexual activity, which is most often associated not with the state of men, and with attitudes, traditions, common myths. Men of this age are more likely to be depressed. Many have a fear of losing their jobs or worsening their social situation. Most often it happens to men, accustomed to lead.
The concept of old age has also changed. It makes sense to distinguish two old age: the first 75 to 82 to 83 years of age and the second older than the 82-83 years. The reason for this is the ever-increasing life expectancy of men in developed countries.
For a man, a very important milestone – the termination of the usual work in connection with retirement. This leaves a serious imprint on the rest of his life. As a rule, aging accelerates, cardiovascular diseases develop, chronic psycho-emotional stress, sexual function is disturbed, interest in life is lost. Differently formed the fate of the men engaged in the work. Their life does not change, they are always busy, do not slow down. Some examples. The great German poet And scientist I. V. Goethe finished the main work of his life “Faust” after 80 years; scientist-biologist K. Lorenz and doctor Bragg after 80 years of active scuba diving, and the actor in 95 years continues to put great performances, and in 98 years, regularly plays the main role and admires the audience with his creativity. The reader may object: it is atypical, it is rare. It all depends on the person and his settings. Man’s attitude to life, his mood significantly affect the quality of life, health and well-being. The first and most important thing – take the installation on health and well-being.
A few tips for men over 50, 60, 70 … Don’t think about age. My father – a wonderful doctor-advised his older patients: “old Age can not be avoided, but it can and should be forgotten.” Always consider yourself young, be energetic, take responsibility for everything you do. Do not feel sorry for yourself, do not whine, do not complain, work, love life and strive to receive joy from it. Know that everything depends on you. Not to relax. Everyone is responsible for their own health and well-being!
My own more than half a century of medical experience and careful analysis of the literature data suggest that a healthy lifestyle, constant high physical, intellectual and sexual activity slow down the aging process and prevent premature aging.