Description of the structure of human blood cells. Blood cells and their functions

Erythrocytes in humans and mammals are nuclear-free cells in the process of philo and ontogenesis of the core and most organelles. Erythrocytes are highly differentiated post-cell structures incapable of division.

The formation of erythrocytes (erythropoes) occurs in the red bone marrow. The duration of their life is 3-4 months, destruction (hemolysis) occurs in the liver and spleen. Before entering blood, the red blood cells consistently pass several stages of proliferation and differentiation in the erythron - red sprout of blood formation.

Typically, red blood cells have the shape of a two-way disc and contain in the main hemoglobin protein, which carries out gas binding.

The main function of the erythrocytes is respiratory - transportation of oxygen and carbon dioxide. In addition, red blood cells are involved in the transport of amino acids, antibodies, toxins and a number of medicinal substances, adsorbing them on the surface of plasmolemma.

The normal number of erythrocytes: in men - (4.0-5.5) 10 12 / l, in women - (3.7-4.7) 10 12 / l.

The number of erythrocytes varies depending on the age and health status. The increase in the number of erythrocytes is most often due to oxygen starvation of tissues or pulmonary diseases congenital heart defects; It may occur during smoking, violation of erythropoese due to a tumor or cyst. A decrease in the number of erythrocytes is a direct indication of anemia (anemia). In advanced cases, under a number of anemia, there is an inhomogeneity of erythrocytes in magnitude and form, in particular with iron deficiency anemia in pregnant women.

Sometimes in the gem, the trivalent iron atom instead of a divalent, and methemoglobin is formed, which is so firmly binds oxygen, which is not able to give it to tissues, resulting in oxygen starvation. Education of methemoglobin in red blood cells can be hereditary or acquired as a result of

actions on erythrocytes of strong oxidants, such as nitrates, some drugs - sulfonamides, local anesthetics (lidocaine).

Leukocytes (White Blood Cells)

The source of leukocytes is a red bone marrow.

Leukocytes differ in structure and appointment. These cells have a kernel. Among them are distinguished granulocytes (neutrophilic, eosinophilic, basophilic), as well as lymphocytes and monocytes. Granulocytes contain granules that are painted with special dyes and visible under a microscope. Neutrophil granules are gray, eosinophils - orange, basophils - purple.

The main purpose of neutrophils is the protection of the body from infections. They phagocytic bacteria, that is, "swallow" and "digest" them. In addition, neutrophils can produce special antimicrobial substances.

Eosinophils remove excess histamine, which appears in allergic diseases. When infected with helminths, eosinophils penetrate the intestinal lumen, they are destroyed there, as a result, substances are released, toxic for helminths.

Basophiles, together with other leukocytes, are actively involved in the inflammatory process, highlighting heparin, histamine, serotonin. The last two substances affect the vascular permeability and the tone of smooth muscles, sharply changing in the focus of inflammation. Heparin binds proteins that came out of cells into the intermediate substance, and weakens their adverse effect on cytoplasmic membranes.

Lymphocytes are the central link of the body's immune system. They carry out the formation of specific immunity, synthesis of protective antibodies, lysis of foreign cells, the reaction of the transplant rejection, provide immune memory. Differentiation of lymphocytes pass in the tissues. Lymphocytes, the ripening of which occurs in the forged gland, are called T-lymphocytes (thymus-dependent). There are several forms of T-lymphocytes. T-killers (killers) carry out the reactions of cellular immunity, lying the alien cells, causative agents of infectious diseases, tumor cells, cells - mutants. T-helpers (helpers), interacting with B-lymphocytes, turn them into plasma cells, so on. Helive the flow of humoral immunity. T-suppressors (oppressors) block excessive reactions in lymphocygigs. There are also T-helpers and T-suppressors that regulate cellular immunity. Memory T cells store information about previously active antigens. B-lymphocytes (drier-dependent) are differentiating in humans in the lymphoid tissue of the intestines, the fabric of the sky and sip almonds. B-lymphocytes carry out the reactions of humoral immunity. Most in lymphocytes are antibodies. B-lymphocytes in response to the effect of antigens as a result of complex interactions with T-lymphocytes and monocytes are converted to plasma cells. Plasma cells produce antibodies that recognize and specifically bind the corresponding antigens. There are 5 main classes of antibodies, or immunoglobulins: JGA, JG G, JG M, JG D, JGE. Among B lymphocytes also distinguish killer cells, helpers, suppressors and cells of immunological memory. O-lymphocytes (zero) do not pass differentiation and are a reserve of T- and B-lymphocytes.

Monocytes are not enough mature cells. They begin to perform their basic functions when they turn into macrophages - large moving cells that are in almost all organs and tissues. Macrophages - peculiar seats. They "eat" bacteria, dead cells, and can "pull out" particles almost equal to them in size. Macrophages, as already mentioned, help lymphocytes in the implementation of immune reactions.

In a healthy person, the number of leukocytes in the blood is inconvenient. After severe physical work, receiving a hot bath, in women during pregnancy, in the process of childbirth and before the start of menstruation it increases. It happens after meals. Therefore, that the results of the analysis be objective, it must be handed over to an empty stomach in the morning, not breakfast, you can drink only a glass of water.

An increase in the number of leukocytes is called leukocytosis, a decrease in leukopenia. The most common leukocytosis occurs in patients with infections (pneumonia, scarletin), purulent diseases (appendicitis, peritonitis, phlegmon), strong burns. Leukocytosis develops for 1-2 hours after the start of intensive bleeding. The attack of gout can also be accompanied by leukocytosis. For some leukemia, the number of leukocytes increases several tens of times.

Although the penetration of microbes into the human body usually stimulates the immune system, as a result of which the number of leukocytes in the blood increases, with some infections the opposite picture is noted. If the body's protective forces are exhausted and the immune system is not able to fight, the number of leukocytes is reduced. For example, leukopenia during sepsis testifies to the serious condition of the patient and unfavorable forecast. Some infections (abdominal typhoid, cortex, rubella, chickenpox, malaria, brucellosis, influenza, viral

hepatitis) suppress the immune system, so they may be accompanied by leukopenia. The decrease in the number of leukocytes is also possible with a systemic red lupus, some leukemia and metastases of bone tumors.

Plates (blood plates)

Also formed from red bone marrow cells. There are flat cells of the irregular round shape with a diameter of 2-5 microns. Man platelets do not have nuclei, these are fragments of cells that are less than half of the erythrocyte. The number of blood platelets in human blood is (180-320) T0 9 / l. Daily fluctuations are occurring: thrombocyte during the night, than at night. The increase in platelets in peripheral blood is called thrombocytosis, reduction - thrombocytopenia.

The main function of platelets is to participate in hemostasis. Platelets help "repair" blood vessels, attaching to damaged walls, and also participate in blood clotting, which prevents bleeding and blood flow from the blood vessel.

The ability of platelets to adhere to a foreign surface (adhesion), as well as glued together (aggregation), under the influence of various reasons. The platelets produce and identify a number of biologically active substances: serotonin (substance that causes the narrowing of blood vessels, reduced blood flow), adrenaline, norepinephrine, as well as substances that have received the name of plate coagulation factors.

For the normal functioning of the human body, as a whole, the existence of a connection between all its bodies is necessary. The circulation of liquids in the body, primarily blood and lymph, is essential in this regard.Blood Transfer hormones and biologically active substances involved in the regulation of the body's activities. In the blood and lymph are special cells that perform protective functions. Finally, these liquids play an important role in maintaining the physicochemical properties of the inner environment of the body, which ensures the existence of organism cells in relatively constant conditions and reduces the effect on them of the external environment.

Blood consists of plasma and uniform elements - blood cells. Recently refer to the latter erythrocytes - red blood cells, leukocytes - White blood cells and thrombocytes - Blood records (Fig. 1). The total amount of blood in an adult is 4-6 liters (about 7% of body weight). In men, blood is somewhat more - on average 5.4 liters, in women - 4.5 liters. Loss of 30% of blood is dangerous, 50% is fatal.

Plasma
Plasma is a liquid part of blood, 90-93% consisting of water. Essentially, the plasma is an intercellular substance of liquid consistency. Plasma contains 6.5-8% proteins, another 2-3.5% are other organic and inorganic compounds. Plasma proteins, albumin and globulins, perform trophic, transport, protective functions, are involved in blood clotting and create a certain osmotic blood pressure. Plasma contains glucose (0.1%), amino acids, urea, uric acid, lipids. Inorganic substances are less than 1% (Na, K, Mg, Ca, Cl, P, etc. ions).

Erythrocytes (from Greek. erythros. - Red) - highly specificized cells designed to transfer gaseous substances. Erythrocytes are of two-screwed disks with a diameter of 7-10 μm, 2-2.5 μm thick. This form increases the surface for the diffusion of gases, and also makes the erythrocyte easily deformed when moving along narrowly convolve capillaries. Erythrocytes do not have a nucleus. They contain protein hemoglobinWith the help of which the air gases are transferred. Neechkin part of hemoglobin (gem) has iron ion.

In the capillaries of light hemoglobin, it forms a fragile compound with oxygen - oxygemoglobin (Fig. 2). Blood, saturated with oxygen, is called arterial and has a bright scarlet color. This blood according to vessels is delivered by each cell of the human body. Oxymoglobin gives oxygen tissue cells and is connected to carbon dioxide gas from them. Poor oxygen blood is dark and called venous. According to the vascular system, venous blood from organs and tissues is delivered to the lungs, where again is saturated with oxygen.

In adults, red blood cells are formed in a red bone marrow, which is in the spongy bone substance. 1 liter of blood contains 4.0-5.0'1012 erythrocytes. The total number of adult erythrocytes reaches 25'1012, and the surface area of \u200b\u200ball erythrocytes is about 3,800 m2. With a decrease in the number of erythrocytes in the blood or a decrease in the amount of hemoglobin in the erythrocytes, the supply of oxygen tissues is disturbed and anemia develops - anemia (see Fig. 2).

The duration of the circulation of erythrocytes in the blood is about 120 days, after which they are destroyed in the spleen and liver. Fabrics of other organs are also capable of destroying red blood cells if necessary, as evidenced by the gradual disappearance of hemorrhages (bruises).

Leukocytes
Leukocytes (from Greek. leukos. - White) - having core cells with a size of 10-15 μm, which can independently move. Leukocytes contain a large number of enzymes capable of splitting various substances. Unlike erythrocytes, which work, being inside the blood vessels, leukocytes carry out their functions directly in the tissues, where they fall through the intercellular slots in the wall of the vessels. In 1 liter of adult, an adult is contained 4.0-9.0'109 leukocytes, the amount may vary depending on the state of the body.

Distinguish several types of leukocytes. To the so-called grass leukocytes include neutrophilic, eosinophilic and basophilic leukocytes, to investigate - lymphocytes and monocytes. Leukocytes are formed in the red bone marrow, and the endless leukocytes - also in lymph nodes, spleen, almonds, thymus (forks). Life expectancy of most leukocytes - from several hours to several months.

Neutrophilic leukocytes (neutrophils)95% of granular leukocytes are. They circulate in the blood not more than 8-12 hours, and then migrate into the tissue. Neutrophils destroy with their enzymes bacteria and tissue decay products. Famous Russian scientist I.I. The swords called the phenomenon of destruction by leukocytes of alien bodies by phagocytosis, and the leukocytes themselves - phagocytes. With phagocytosis, neutrophils die, and the enzymes allocated by them destroy the surrounding tissues, contributing to the formation of an ulcer. Pump consists mainly of the residues of neutrophils and food decomposition products. The number of neutrophils in the blood increases sharply with acute inflammatory and infectious diseases.

Eosinophilic leukocytes (eosinophils) - It is about 5% of all leukocytes. Especially a lot of eosinophils in the intestinal mucosa and respiratory tract. These leukocytes are involved in immune (protective) organism reactions. The amount of eosinophils in the blood increases with gliscate invasions and allergic reactions.

Basophilic leukocytesabout 1% of all leukocytes are accounted for. Basophiles produce biologically active substances of heparin and histamine. Heparin basophilov prevents blood clotting in the focus of inflammation, and histamine expands capillaries, which contributes to the resorption and healing processes. Basophiles also carry out phagocytosis and are involved in allergic reactions.

The number of lymphocytes reaches 25-40% of all leukocytes, but they prevail in the lymph. T-lymphocytes are distinguished (formed in thymus) and in lymphocytes (formed in the red bone marrow). Lymphocytes perform important functions in immunity reactions.

Monocytes (1-8% leukocytes) are in the circulatory system of 2-3 days, after which they migrate into tissues, where they are converted to macrophages and perform their main function - the protection of the body from foreign substances (participate in immune reactions).

Thrombocytes
Platelets are small calves of various shapes, in size 2-3 microns. The amount of them reaches 180.0-320.0'109 in 1 liter of blood. Platelets are involved in blood clotting and stopping bleeding. The lifespan of platelets is 5-8 days, after which they fall into the spleen and the lungs, where they are destroyed.

The most important protective mechanism that protects the body from blood loss. It is a stop of bleeding by forming a blood clot (Trombus), a tightly clogging hole in a damaged vessel. In a healthy person, bleeding in the injection of small vessels stops for 1-3 minutes. In case of damage to the wall of the blood vessel, platelets are glued and adhered to the edges of the wound, biologically active substances are released from platelets, which cause narrowing of vessels.

With more significant damage, the bleeding stop occurs as a result of a complex multistage process of enzymatic chain reactions. Under the influence of external reasons, blood coagulation factors are activated in damaged vessels: the prolrombin plasma protein, which is formed in the liver, turns into thrombin, which, in turn, causes the formation of an insoluble fibrin fibrinogen plasma protein. The fibrin threads form the bulk of the tomb, in which numerous blood cells are stuck (Fig. 3). The resulting thrombus clogs the place of damage. Blood coagulation occurs in 3-8 minutes, but in some diseases this time may increase or decrease.

Groups of blood

Practical interest represents knowledge of blood group. On the basis of division into groups, there are different types of combinations of erythrocyte antigens and plasma antibodies, which are a hereditary assembly of blood and are formed at the initial stages of the body's development.

It is customary to allocate four main blood groups by the system AV0: 0 (I), A (II), B (III) and AB (IV), which is taken into account when overflowing it. In the middle of the 20th century it was assumed that the blood of group 0 (i) Rh is compatible with any other groups. People from 0 (i) by a group of blood were considered universal donors, and their blood could be transferred to anyone in need, and they themselves are only blood I group. People who have an IV group of blood were considered universal recipients, they were injected by blood of any group, but their blood is only people with the IV group.

Now in Russia according to life indications and in the absence of one -roads on the system, the blood components (with the exception of children) is allowed to transfusion of rhesse-negative blood 0 (i) of the recipient group with any other group of blood in an amount up to 500 ml. In the absence of a single-line plasma, the recipient may be overflow of the AB (IV) group.

When the blood and recipient blood and recipient are missed, the red blood cells are glued together and their subsequent destruction, which can lead to the death of the recipient.

In February 2012, scientists from the United States in collaboration with Japanese and French colleagues opened two new "additional" blood groups, including two proteins on the surface of the erythrocytes - ABCB6 and ABCG2. They relate to transport proteins - participate in the transfer of metabolites, ions inside the cell and from it.

To date, more than 250 antigens of blood groups are known combined in 28 additional systems in accordance with the laws of their inheritance, most of which are much less common than AB0 and the Rh.

Resh factor

When blood transfusion also takes into account the Rh Factor (RH factor). Like blood groups, it was opened by the Viennese scientist K. Landstyner. This factor has 85% of people, their blood is reserves-positive (RH +); In others, this factor is absent, their blood is reserves-negative (Rh-). Heavy consequences have a donor blood transfusion with RH + man with Rh. The rhesus factor is important for the health of the newborn and when re-pregnancy of a rhes-negative woman from a rhesus-positive man.

Lymph

Lymph recesses the fabrics on the lymphatic vessels, which is part of the cardiovascular system. According to the composition of Lymph, it resembles a blood plasma, but there are fewer proteins in it. The lymph is formed from the tissue fluid, which, in turn, arises by filtration of blood plasma from blood capillaries.

Research of blood

Blood research has a large diagnostic value. The study of blood pattern is carried out in many indicators, among which the number of blood cells, the hemoglobin level, the content of various substances in plasma, etc. Each indicator taken separately, in itself is not specific, but receives a certain value only in conjunction with other indicators and in connection With a clinical picture of the disease. That is why each person repeatedly rejects a drop of his blood for analysis. Modern research methods allow, on the basis of studying one of this drop, a lot to understand in a state of human health.

Let's start with the cells that are most in the blood - red blood cells. Many of us know that red blood cells carry oxygen to organs of organs and tissues, thereby ensuring the breathing of each smallest cell. Due to what they are able to do it?

Erythrocyte, - What is he? What is his structure? What is hemoglobin?

So, the erythrocyte is a cell that has a special form of a two-way disc. There is no kernel in the cage, and most of the cytoplasm of the erythrocyte occupies a special protein - hemoglobin. Hemoglobin has a very complex structure, consists of a protein part and an iron atom (Fe). It is hemoglobin that is an oxygen carrier.

This process occurs as follows: Available atom of iron attaches an oxygen molecule when the blood is in light man during the breath, then the blood according to the vessels through all organs and tissues, where oxygen is discharged from hemoglobin and remains in cells. In turn, carbon dioxide is distinguished from the cells, which joins the atom of iron hemoglobin, the blood returns to the lungs, where gas exchange occurs - carbon dioxide with exhalation is removed, oxygen is connected instead and the whole circle is repeated again. Thus, hemoglobin transfers oxygen to cells, and carbon dioxide takes out of the cells. That is why man inhales oxygen, and carbon dioxide exhales. Blood in which red blood cells are saturated with oxygen, has brightly aluminous color and called arterial, and blood, with erythrocytes, saturated with carbon dioxide, has dark - red and called venous.

In the blood of man, red blood cell lives 90 - 120 days, after which it is destroyed. The phenomenon of the destruction of the erythrocytes is called hemolysis. Hemolysis takes place mainly in the spleen. Part of the red blood cells are destroyed in the liver or directly in vessels.

For details on deciphering a general blood test read in Article: General blood analysis

Blood group antigens and reserves - factor

On the surface of the erythrocytes there are special molecules - antigens. There are several varieties of antigens, therefore the blood of different people differs from each other. It is antigens that form a blood group and a reserves - factor. For example, the presence of antigens 00 - forms the first group of blood, the antigens 0a - the second, 0B - the third and antigens of AV - fourth. Rh - factor is determined by the presence or absence of an antigen RH on the surface of the erythrocyte. If the RH antigen is available on erythrocyte, then the blood of a positive rear - factor, if there is no blood, then blood, respectively, with a negative rhesus - factor. Definition of blood group and reserves - factor is of great importance when overflowing blood. Miscellaneous Antigens "will be entrited" with each other, which causes the destruction of red blood cells and a person can perish. Therefore, it is possible to overflow only the blood of the same group and one Rh - factor.

Where does erythrocyte in the blood appear?

Erythrocyte develops from a special cell - predecessor. This cell - the predecessor is located in the bone marrow and is called eritroblast. The erythroblast in the bone marrow passes several stages of development to turn into erythrocytes and during this time is divided several times. Thus, from one erythrobusta, 32-64 red blood cells are obtained. The entire process of ripening erythrocytes from the erythrobusta passes in the bone marrow, and ready-made red blood cells enter the bloodstream instead of "old" to be destroyed.

Reticulocyte, erythrocyte predecessor
In addition to erythrocytes in the blood there are reticulocytes. Reticulocyte is a bit "unwarked" erythrocyte. Normally, in a healthy person, their number does not exceed 5 - 6 pieces per 1000 erythrocytes. However, in the case of acute and large blood loss, erythrocytes and reticulocytes are out of bone marrow. This happens, because the reserve of finished red blood cells is insufficient to replenish blood loss, and for ripening new it takes time. Due to this circumstance, the bone marrow "produces" a bit "immature" reticulocytes, which, however, can already perform the main function - tolerate oxygen and carbon dioxide.

What form are erythrocytes?

Normally, 70-80% of red blood cells have a spherical biconed shape, and the remaining 20-30% may be of various shapes. For example, simple spherical, oval, thicker, cup-shaped, etc. The form of erythrocytes may be impaired with various diseases, for example, erythrocytes in the form of a sickle are characteristic of sickle-shaped cell anemia, oval form with a lack of iron, vitamins in 12, folic acid.

For details on the reasons for reduced hemoglobin (anennels), read in the article: Anemia

Leukocytes, leukocyte types - lymphocytes, neutrophils, eosinophils, basophiles, monocytes. The structure and functions of various types of leukocytes.

Leukocytes are a large class of blood cells, which includes several varieties. Consider the varieties of leukocytes in detail.

So, first of all, leukocytes are divided into granulocytes (have graininess, granules) and agranulocytes (do not have granules).
Granulocytes include:

1. basophiles

Agranulocytes include the following types of cells:

Neutrophil, appearance, structure and functions

Neutrophils are the most numerous variety of leukocytes, in the normal blood of them containing up to 70% of the total number of leukocytes. That is why the detailed consideration of the types of leukocytes will begin with them.

Where does this name come from - neutrophil?
First of all, we find out why neutrophil is so called. In the cytoplasm of this cell there are granules, which are painted with dyes having a neutral reaction (pH \u003d 7.0). That is why this cell was called: neutophil - has affinity for neutrealtan dyes. These neutrophilic granules have the form of a shallow grain of purple - brown.

What does neutrophil look like? How does it appear in the blood?
Neutrophil has a rounded shape and unusual shape of the nucleus. The kernel is a wand or a 3 - 5 segments interconnected by subtle hill. Neutrophil with a kernel in the shape of a stick (rod) is a "young" cell, and with a segmental core (segmented) - "mature" cell. In the blood, most neutrophils segmented (up to 65%), the rods in the norm are only up to 5%.

Where do neutrophils come to blood? Neutrophil is formed in the bone marrow from its cell - predecessor - myeloblast Neutroofyl. As in the situation with the erythrocyte, the cell - the predecessor (myeloblast) passes several stages of ripening, during which it is also divided. As a result, 16-32 neutrophil matures from one myeloblast.

Where and how much does Neutrophil live?
What happens to neutrophil further after its ripening in the bone marrow? Mature neutrophil lives in the bone marrow for 5 days, after which it goes into the blood, where he lives in the vessels 8 - 10 hours. Moreover, the bone marrow pool of mature neutrophils 10 is 20 times more than the vascular pool. From the vessels they go into fabrics, of which no longer return to the blood. In the tissues of neutrophils live 2 - 3 days, after which they are destroyed in the liver and spleen. So, mature neutrophil lives only 14 days.

Granules of neutrophil - what is it?
In the cytoplasm of neutrophil there are about 250 types of granules. These granules contain special substances that help to perform its function neutrophil. What is contained in granules? First of all, these are enzymes, bactericidal substances (destroying bacteria and other pathogens), as well as regulatory molecules that control the activity of neutrophils themselves and other cells.

What functions perform neutrophil?
What does neutrophil do? What is his purpose? The main role of neutrophil is protective. This protective function is implemented due to the ability to phagocytosis. Phagocytosis is a process during which neutrophil approaches a pathogen agent (bacteria, virus), captures it, puts inside himself and with the help of enzymes his granules kills a microbe. One neutrophil is able to absorb and neutralize 7 microbes. In addition, this cell is involved in the development of an inflammatory response. Thus, neutrophil is one of the cells providing human immunity. Neutrophil works, carrying out phagocytosis, in vessels and tissues.

Eosinophils, appearance, structure and functions

What does eosinophil look like? Why is the so called?
Eosinophil, like neutrophil, has a rounded shape and a rolling-shaped or segmental shape of the kernel. Granules located in the cytoplasm of this cell are quite large, the same size and shape, painted in brightly orange, reminding red caviar. Eosinophil granules are painted with dyes having a sour reaction (pH eosinophil - has affinity for eosiny

Where is eosinophil formed, how much does he live?
Like neutrophil, eosinophil is formed in the bone marrow from the cell - predecessor - eosinophilic myeloblast. In the process of maturation, the same stages are underway as neutrophil, however other granules have. Eosinophil granules contain enzymes, phospholipids and proteins. After full ripening, eosinophils live a few days in the bone marrow, then go into the blood, where they circulate 3 - 8 hours. From blood, eosinophils go into tissues in contact with the outer medium - the mucous membranes of the respiratory tract, the urinary tract and intestines. In total, eosinophil lives 8 - 15 days.

What does eosinophil do?
Like neutrophil, eosinophil provides a protective function due to the ability to phagocytosis. Neutrophil is subjected to phagocytosis pathogenic agents in tissues, and eosinophil on mucous respiratory and urinary tract, as well as intestines. Thus, neutrophil and eosinophil perform a similar function, only in different places. Therefore, eosinophil is also a cell providing immunity.

A distinctive feature of eosinophil is its participation in the development of allergic reactions. Therefore, people having allergies on something usually increases the number of blood eosinophils.

Basophil, Appearance, Building and Functions

How do they look? Why so called?
This type of blood cells are the smallest, they are contained only 0 - 1% of the total number of leukocytes. They have a rounded shape, a rod or segmented kernel. The cytoplasm contains various in the magnitude and shape of the granules of dark purple color, which have an appearance resembling a black caviar. These granules are called basophilic graininess. The graininess is called basophilic, since painted with dyes having an alkaline (BASIC) reaction (pH\u003e 7). Yes, and the entire cell is named so because it has an affinity for major dyes: bazofeta - bas.iC.

Where does basophil come from?
Basophil is also formed in the bone marrow from the cell - predecessor - basophilic myeloblast. In the process of ripening, the same stages are underway as neutrophil and eosinophil. Basophila granules contain enzymes, regulatory molecules, proteins involved in the development of an inflammatory response. After full ripening, basophiles overlook the blood, where no more than two days live. Further, these cells leave the bloodstream, go into the body's tissues, however, what happens to them there - today it is unknown.

What functions are assigned to basophil?
During blood circulation, basophiles participate in the development of an inflammatory response, are able to reduce blood coagulation, as well as take part in the development of anaphylactic shock (type of allergic reaction). Basophiles produce a special regulatory molecule of interleukin IL-5, which increases the amount of eosinophils in the blood.

Thus, basophil is a cell involved in the development of inflammatory and allergic reactions.

Monocyte, Appearance, Building and Functions

What is monocyte? Where is it produced?
The monocyte is agranulocyte, that is, there is no grain in this cell. This is a large cell, a little triangular shape, has a large core, which is a rounded shape, bean-like, vane, row and segmented.

The monocyte is formed in the bone marrow from monoblast. In its development there are several stages and several divisions. As a result, mature monocytes do not have a bone marrow reserve, that is, after education immediately go into the blood, where 2 - 4 days live.

Macrophage. What is this cage?
After that, part of the monocytes dies, and the part goes into fabric, where a little modifies - "rushing" and becomes macrophages. Macrophages are the biggest cells in the blood that have a core oval or rounded form. Blue cytoplasm with lots of vacuoles (emptiness), which give her a frothy look.

In the body tissues, macrophages live several months. Once from the bloodstream in fabrics, macrophages can become resident cells or wandering. What does it mean? Resident macrophag all the time of his life will spend in the same tissue, in the same place, and the wandering constantly moves. Resident macrophages of various body tissues are different in different ways: for example, in the liver, these are kipfer cells, in the bones - osteoclasts, in the brain - microglyal cells, etc.

What do monocytes and macrophages do?
What functions do these cells perform? The blood monocyte produces various enzymes and regulatory molecules, and these regulatory molecules can contribute to both the development of inflammation and, on the contrary, to slow down the inflammatory response. What do at this particular point and in a certain situation monocyte? The answer to this question does not depend on it, the need to strengthen the inflammatory response or weaken is accepted by the body as a whole, and the monocyte only executes the command. In addition, monocytes are involved in healing wounds, helping to speed up this process. Also contribute to the restoration of nerve fibers and the growth of bone tissue. The macrophage in the tissues is concentrated on the performance of the protective function: it phasizes the pathogens, suppresses the reproduction of viruses.

Lymphocyte appearance, structure and functions

The appearance of the lymphocyte. Stages of ripening.
Lymphocyte - rounded cell of various sizes, having a large round core. The lymphocyte is formed from the lymphoblast in the bone marrow, as well as other blood cells, is divided several times during the ripening process. However, in the bone marrow, the lymphocyte passes only "general training", after which it finally matures in Timus, spleen and lymph nodes. Such a ripening process is necessary, since the lymphocyte is an immunocompetent cell, that is, a cell that provides all the variety of organism immune reactions, thereby creating its immunity.
The lymphocyte, which has passed the "special training" in Timus, is called T - lymphocyte, in lymph nodes or spleen - B - lymphocyte. T - lymphocytes are less than B - lymphocytes in size. The ratio T and B cells in blood is 80% and 20%, respectively. Blood is a vehicle for lymphocytes, which delivers them to the place in the body where they are necessary. Lifting lymphocytes on average 90 days.

What do lymphocytes provide?
The main function and T-, and in-lymphocytes are protective, which is carried out by participating in their immune reactions. T - lymphocytes predominantly phagocyse pathogenic agents, destroying viruses. Immune reactions carried out by T-lymphocytes are called non-specific resistance. Nonspecific it is because these cells act equally in relation to all pathogens of microbes.
B - lymphocytes, on the contrary, destroy bacteria, producing specific molecules against them - antibodies. On each type of bacteria B - lymphocytes produce special antibodies that can destroy only this type of bacteria. That is why B - lymphocytes form specific resistance. Nonspecific resistance is directed mainly against viruses, and specific - against bacteria.

The participation of lymphocytes in the formation of immunity
After in - lymphocytes once met with any microbe, they are capable of forming memory cells. It is the presence of such memory cells that causes the stability of the organism to infection caused by this bacteria. Therefore, in order to form memory cells, vaccinations against particularly dangerous infections are used. In this case, a weakened or dead microbe is introduced into the human body in the form of vaccinations, a person moves in a light form, the result of memory cells are formed, which ensure the stability of the body to this disease throughout life. However, some memory cells are saved for life, and some live a certain period of time. In this case, vaccinations make several times.

Platelet, appearance, structure and functions

Structure, platelet formation, their types

Platelets are small cells of round or oval shape, not having a kernel. When activated, "increased", acquired by star form. Thrombocytes in the bone marrow from megakarisoblast. However, the formation of platelets has features uncharacteristic for other cells. From the megakarisoblast is formed megakaryocytewhich is the largest bone marrow cage. The megacariocyte has a huge cytoplasm. As a result of ripening in cytoplasm, separation membranes grow, that is, a single cytoplasm is separated into small fragments. These small fragments of the megacariocyte "are packed", and this is independent platelets. The bone marrow platelets go to the bloodstream, where they live 8 to 11 days, after which they are dying in the spleen, liver or lungs.

Depending on the diameter, the platelets are divided into microgram, having a diameter of about 1.5 microns, normopforms with a diameter of 2-4 microns, macro-forming - diameter 5 microns and megalo-forming - diameter 6 - 10 microns.

What are platelets answer for?

These small cells perform very important functions in the body. First, platelets maintain the integrity of the vascular wall and help its recovery during damage. Secondly, platelets stop bleeding, forming a thrombus. It is platelets first turn out to be in the focus of a break of the vascular wall and bleeding. They, sticking together with each other, form a thrombus, which "sticks out" the damaged wall of the vessel, thereby stopping bleeding.

Thus, blood cells are essential elements in ensuring the basic functions of the human body. Nevertheless, some of their functions still remain unexplored.

The blood volume in the body of an adult is about 5 liters. There are 2 components in the blood: plasma (intercellular substance) - 55-60% blood volume (about 3 l) and uniform elements - 40-45% of blood volume. Plasma It consists of 90% water, organic 9% and inorganic 1% substances. Proteins make up 6% of all plasma substances, albumin, globulins and fibrinogen are dominated among them. E.ratropocytes (red blood tales) - 4.3-5.3 in men, and 3.9-4.5 10 12 / l in women leukocytes (white blood cells) - 4.8-7.7 10 9 / l, thrombocytes (Blood plates) - 230-350 10 9 / l. HemogrbutmMA - clinical blood test. Includes data on the number of all uniform elements of the blood, their morphological features, EE, the hemoglobin content, color indicator, hematocrit, the ratio of various types of leukocytes, and others. Blood function is transport. Maintaining homeostasis. Protective function. Hemokoagulation. Mesodermal Parenchima, or mezenchima- germing device of multicellular animals and man. Mesenchyma arises due to cells of different germinal leaflets (ectoderms, entoderms and mesoderms). From the mesenchym, connective tissue, blood vessels, main muscles, visceral skeleton, pigment cells and lower layer of the connective tissue of the skin are formed.

2. Erythrocytes. Erythrocytes (Red blood tales) - Non-surfactant uniform elements of blood containing hemoglobin. The main function of the erythrocytes is the transportation of oxygen and carbon dioxide. Erythrocytes constitute the bulk of blood shaped blood elements. The biconued erythrocyte disc ensures the maximum ratio of surface area to volume. In addition to participating in tissue respiration, the erythrocytes perform nutrient and protective functions - they deliver nutrients to the cells of the body, and also bind toxins and transfer the antibodies on their surface. In addition, erythrocytes provide the maintenance of acid-base equilibrium in the blood. Enzymes contained in erythrocytes catalyze vital biochemical processes. Erythrocytes take part in the blood coagulation process. The average diameter of human erythrocytes is 7-8 microns. The average life expectancy of erythrocytes is 3-4 months. Old erythrocytes are destroyed in the spleen. The dead erythrocytes come to replace the young forms of red blood cells - reticulocytes .. Normally contain in the blood of 0.2-1.2% of the total erythrocyte. Retik Londi contains grain-mesh structures - aging mitochondria, remnants of the endoplasmic network and ribosomes. The presence of grain-mesh structures is detected with a special color - cresil blue. 3. Leukocytes.The nuclear cells of the spherical form in size are larger than erythrocytes. In 1 liter of adult blood, it contains 4.8-7.7x 10 9. In the cytoplasm of leukocytes there are primary azurophilic granules (lysosomes) and secondary. Depending on the type of granules, leukocytes are divided into granulocytes (grainy) and agranulocytes (inexistible). Granulocytes (neutrophils, basophiles and eosinophils) contain specific and nonspecific granules. Agranulocytes (monocytes and lymphocytes) contain only nonspecific azurophilic granules. Luxcites have contractic proteins (Aktin, MIOSIN) and are able to exit blood vessels, penetrating between endothelial cells. Leukocytes are involved in protective reactions, destroying microorganisms and capturing foreign particles, carrying out the reaction of humoral and cellular immunity. The percentage of various types of leukocytes, determined when calculating them in a colored blood smear under the microscope. Leukocyte formula of a healthy adult person (extreme fluctuations,%)

5. Lymphocytes and monocytes. Lymphocytes:Under normal conditions, 27-45%. Cells with erythrocyte size. The life expectancy of lymphocytes varies widely from several hours to 5 years. Lymphocytes play a central role in immune reactions. Lymphocytes exit vessels into the connecting tissue in response to specific signals. Lymphocytes can migrate through the Bazal Membrane of Epithelials and implemented in the epithelium. The kernel occupies most of the cell, has a round, oval or slightly legs. The structure of chromatin is compact, the kernel impresses the chuck. The cytoplasm in the form of a narrow kayma, is painted basophilic in blue color. In terms of cells in the cytoplasm, an azurophilic graininess of lymphocytes is detected in the cytoplasm. Lymphocytes are divided into various categories according to their value: small (4, .5-6 μm), medium (7-10 μm) and large (10-18 microns). Lymphocytes include similar morphologically, but differing functionally cells. The following types are distinguished: in lymphocytes, T-lymphocytes (differentiation in thymus) and NK cells. T - lymphocytes are predominantly blood lymphocytes (80%). The cell predecessor T - lymphocytes enters the thymus from the red bone marrow. Mature lymphocytes leave thymus and they are detected in peripheral blood or lymphoid organs into lymphocytes are 10% of blood lymphocytes. Plasma cells in which they are differentiated are capable of producing appropriate antigens against specific antibodies. NK cells are not t, and not in lymphocytes. Approximately 10% of all lymphocytes. Contain cytolytic granules, destroying transformed by virus infected and alien cells. Monocytes: The largest leukocytes ranging from 12 to 20 microns. Content in conditions of norms 4-9%. The kernel is large, loose, with a non-uniform distribution of chromatin. The shape of the kernel is a bean-like leopard, horseshoe, less often round or oval. Pretty wide range of cytoplasm painting less basophilic than lymphocytes. Can be detected small azurophilic graininess. The cytoplasm contains numerous lysosomes and vacuoles. There are minor elongated mitochondria. Golgi complex is well developed. The main function of monocytes and macrophages generated from them - phagocytosis. Lizosomal enzymes are involved in digestion, as well as intracellular peroxide. Structures that determine the features of the cells of the immune system have antigenic properties. They got the name "Cluster of Differentiation" (differentiation indicator) and CD designation.

6. Platelets: These are nuclear-free ziestoplasm fragments, separated in a red bone marrow from megakaryocytes (giant cells) and circulating blood. They have a size of 2-4 microns. Total amount of blood 230-350 10 9 per 1 liter. Life expectancy 4 days. In the central part, the platelet contains a granuleer - a pronounced grain, which is represented by granules, glyben glybers, EPS, mitochondria and is azurophilic. The peripheral part of platelet is a homogeneous hyalomer, which is painted differently depending on the age of platelet. On the platelet surface there is a large number of phosphate groups - components of membrane phospholipids and phosphoproproteins.

7. Embryonic hematopois.Hemopois (lat. haemopoesis), blealing - This is the process of education, development and ripening of cells blood - leukocyte, erythrocyte, thrombocyte W. vertebrae. Allocate: embryonic (intrauterine) hemopoies; Post-empty hematopois. Embryonic hemopois:In the development of blood as tissue in the embryonic period, 3 main stages can be distinguished, consistently replacing each other - messelistic, hepatolyenal and medullar. First, mes loan stage - this is the appearance of blood cells in off-site organs, namely in the mesenchym, the walls of the yolk bag, mesenchym chorione and stem. At the same time, the first generation of blood stem cells (CCC) appears. The mesing stage proceeds from the 3rd to the 9th week of the development of a human embryo. Second, hepatolyenal stage begins with the 5-6th week of fetal development when liver It becomes the main organ of hemopois, it produces the second generation of blood stem cells. Blood-formation in the liver reaches a maximum after 5 months and ends before birth. The Liver CCM populates thymus, spleen and lymph nodes. The third, medullar (bone marrow) stage - this is the appearance of the third generation of blood stem cells in red bone marrowwhere hematopois begins from the 10th week and gradually increases for birth. After birth, the bone marrow becomes the central hematopois organ . Post-Imbrium hematopois:Post-emptilic hematopois is a process physiological regeneration Blood, which compensates for the physiological destruction of differentiated cells. It is divided into myelopoese and lymphoposoez. MielopoEZ It occurs in myeloid fabric located in the epiphyses of tubular and cavities of many spongy bones. Erythrocytes, granulocytes, monocytes, platelets, as well as predecessors of lymphocytes are developing here. In myeloid fabric there are stem cells of blood and connective tissue. The predecessors of lymphocytes gradually migrate and populate thymus, spleen, lymph nodes and some other organs. Lymphopoese It occurs in lymphoid fabric, which has several varieties presented in Timus, spleen, lymph nodes. It performs the functions of the formation of T- and B-lymphocytes and immunocytes (for example, plasmacites). Myeloid and lymphoid fabrics are varieties of connective tissue, i.e. belong to the tissues of the inner medium. They present two main cell lines - cells of reticular tissue and hemopoietic cells.

9. Erythrocytopoese. It begins with a stem blood-made cage. Through the step of the colony forming multipotent cell (coherem), a bustaceous (BOE-E) is formed and further a colony-forming unit of erythrocytes (Core e). Cells of these colonies are sensitive to proliferation and differentiation regulation factors .. in the IV class turn on basophilic, polychromatophilic and oxyfly erythroblasts. Proyeritrocytes, then the reticulocytes comprehend the V-th class and, finally, the erythrocytes (VI class) are formed. In the erythropoese at the stage of the oxificial erythroblast, the kernel is pushing. In general, the cycle of the development of the erythrocyte before the reticulocyte exit to the blood continues until 12 days. The general direction of erythropois is characterized by the following basic structural and functional changes: a gradual decrease in the size of the cell, accumulating in the cytoplasm of hemoglobin, the reduction of the organelle, the decrease in the basophilia and the increase in the cytoplasm oxipliament, the core seal, followed by its release from the cell composition. In the erythroblastic islands, the erythroblasts are absorbed by the micropinocytosis of iron supplied by macrophages, for the synthesis of hemoglobin. Development of red blood cells It occurs in the myeloid fabric of the red bone marrow. Only mature red blood cells and some reticulocytes arrive in the peripheral blood.

10. Granulocyteopozez. IV class Mieloblast. Size 12-25 microns. V Class Proselocyte - the kernel of the rough structure, there are nuclei. The cytoplasm is sharply basophil. Non-specific graininess appears. Myelocyte is a size of 10-20 microns. The kernel is round or oval, nucleoli are not detected. The cytoplasm contains nonspecific and specific grain. Depending on the type of specific grain, neutrophilic, eosinophilic and basophilic myelocytes are isolated. Metamielocytes (young forms) have a number of common properties: not divided, found in the blood, contain a bean-shaped core. Class VI Ragged cells - the kernel looks like a thick curved wand without jumpers. Segmented cells - the kernel consists of several segments separated by narrow hats.

11. Monocytopoese.V Class-promotionalocyte. The kernel is round, large, and there is no granules in the cytoplasm. The final stage of differentiation of monocytic cell cells is not a monocyte, but a macrophage, which is outside the vascular bed. Differentiation of cells during monocytopoese is characterized by an increase in the size of the cell, the acquisition of a bean-shaped core, a decrease in the basophilia of the cytoplasm, the transformation of the monocyte into macrophages. The main function of monocytes and macrophages generated from them - phagocytosis. Thrombocytopoese. Megakaroblast is an immature giant bone marrow cage. Size 25-40 μm. The kernel is a big irregular shape, contains up to three nucleoli. The basophilina cytoplasm, a narrow strip surrounds the kernel. Megakaryocyte Giant CMM cell 40-45 microns. When moving from the megakarisoblast, the kernel becomes polyploid. The shape of the nucleus is incorrect joining. Basophilic cytoplasm contains azurophilic grain. The megacariocyte "pushes" part of its cytoplasm (in the form of processes) in the slit of the capillaries of the red bone marrow. After that, the cytoplasm fragments are separated in the form of plates ("platelets"). The remaining poise-containing part of the megacariocyte can restore the volume of the cytoplasm and form new platelets.

13Limfocyto and plasmocytopoies.the lymphocytopoese in the embryonic and post-empty periods is carried out in stages, replacing different lymphoid bodies. In T- and in B-lymphocytopoese, there are three stages:

Bone marrow stage;

stage of antigen-independent differentiation carried out in central immune bodies;

stage of antigen-dependent differentiation carried out in peripheral lymphoid organs. At the first stage of differentiation of stem cells, predecessor cells are formed, respectively, T- and B-lymphocytopoede. In the second stage, lymphocytes are formed, capable of recognizing antigens only. In the third stage, effector cells capable of destroying and neutralize the antigen are generated from cells of the second stage. The process of development of T- and B-lymphocytes has both general patterns and essential features and therefore be subject to separate consideration.

First stage T-lymphocytopoese is carried out in the lymphoid tissue of the red bone marrow, where the following cell classes are formed:

1 class - stem cells; Grade 2 - semi-mass-predecessor cells of lymphocytopoede; Grade 3 - unipotent T-poin-mixed cells predecessors of T-lymphocytopoede, these cells migrate to the bloodstream and with blood reach thymus. Second phase - The stage of antigen-independent differentiation is carried out in the timus cortical substance. Here continues the further process of T-lymphocytopoede. Under the influence of the biologically active substance, the thymsimin, isolated by stromal cells, unipotent cells are converted to T-lymphoblasts - grade 4, then in T-prolimphocytes - grade 5, and the last 6th grade in T-lymphocytes. In the thymus, three subpopulations of T-lymphocytes are developing from unipotent cells:

• suppressors.

As a result of the second stage, receptor (afferent or T0) T-lymphocytes are formed - killers, helpers, suppressors. At the same time, lymphocytes in each of the subpopulations differ from each other receptors, however, there are clones of cells that have the same receptors. T-lymphocytes that have receptors and to their own antigens are formed in the thymus, but such cells are destroyed here by macrophages. Third stage - The stage of antigen-dependent differentiation is carried out in the T-zones of peripheral lymphoid organs - lymph nodes, spleen and others, where conditions are created to meet the antigen with T-lymphocyte (killer, helper or suppressor) having a receptor to this antigen. Under the influence of the corresponding antigen, the T-lymphocyte is activated, changes its morphology and turns into a T-lymphoblast, or rather in T-immunoblast, since this is no longer a cell 4 cell (formed in the thymus), and the cell resulting from the lymphocyte under the influence of the antigen. The process of converting T-lymphocyte in T-immunoblast is called blastransformation reaction. After that, the T-immunoblast arising from T-receptor killer, a helper or a suppressor, proliferates and forms a clone of cells. T-killer immunoblast gives a clone of cells, among which are available:

T-memory (killers);

T-killers or cytotoxic lymphocytes that are effector cells providing cellular immunity, that is, the protection of the body from foreign and genetically modified intrinsic cells. After the first meeting of the alien cell with receptor T-lymphocyte, the primary immune response is developing - blastransformation, proliferation, formation of T-killers and the destruction of an alien cell. T-cells of memory when re-encountered with the same antigen provide the secondary immune response to the same mechanism, which proceeds faster and stronger than the primary one.

14. Classification, sources of development .... Connecting fabrics is a fabric complex mesenchymal origininvolved in maintaining homeostasis the inner medium and differ from other tissues less need for aerobic oxidative processes. Together with blood and lymphooconcing fabrics are combined into the so-called. " interior fabrics" Like all tissues, they consist of cells and an intercellular substance. The intercellular substance, in turn, consists of fibers and the main, or amorphous, substance. The connecting tissue is more than half of human body weight. She participates in the formation stroms Organs, interlayers between other tissues in organs, forms a skin of the skin, skeleton. Connecting fabrics form and anatomical formations - fascia and capsules, tendons and bundles, cartilage and bones. The polyfunctional nature of the connective tissues is determined by the complexity of their composition and organization.

Functions: Trophic function (In a broad sense) is associated with the regulation of the nutrition of various tissue structures, with participation in the metabolism and maintenance of homeostasis of the inner environment of the body. In ensuring this function, the main role is played by the basic substance through which the vehicles of water, salts, nutrient molecules are carried out. Protective function It is to protect the body from mechanical impacts and disposal of alien substances incoming from outside or generated inside the body. This is ensured by physical protection (for example, bone tissue), as well as phagocytic activities. macrofhagha and immunocompetent cells involved in the reactions of cellular and humoral immunity. Reference, or biomechanical, the function is provided primarily by collagen and elastic fibers forming the fibrous bases of all organs, as well as the composition and physicochemical properties of the intercellular substance of skeletal tissues (for example, mineralization). The denser of the intercellular substance, the more significant, the reference, biomechanical function; Example - bone tissue. Plastic function The connective tissue is expressed in adaptation to the changing conditions of existence, regeneration, participation in the replacement of body defects during their damage (example - the formation of scar tissue during wound healing). Morphogenetic, or structure-forming, the function is manifested in the formation of tissue complexes and ensuring the general structural organization of organs (the formation of capsules, intraogenous partitions), as well as the regulating effect of certain components on the proliferation and differentiation of cells of various tissues. Classification: Varieties of connective tissue differ in each other by the composition and ratio of cells, fibers, as well as the physicochemical properties of the amorphous intercellular substance. Connecting fabrics are divided into three types:

actually connective tissue,

connecting fabrics with special properties,

skeleton fabrics.

Actually connecting fabric Includes:

loose fibrous connecting fabric;

dense unformed connecting fabric;

dense decorated connective tissue.

Connecting fabrics with special properties include:

reticular tissue;

fat fabrics;

mucous tissue.

Skeleton fabrics include:

cartilage fabrics

bone tissue

cement and dentin tooth.

In the anatomical structure of the body of a person, cells, fabrics, organs and systems of organs, which carry out all vital functions are distinguished. There are only about 11 such systems:

• nervous (CNS);
• digestive;
• cardiovascular;
• bleale;
• breathing;
• musculoskeletal;
• lymphatic;
• endocrine;
• excretory;
• sex;
• skin-muscular.

Each of them has its own characteristics, the structure and performs certain functions. We will consider the part of the blood system that is its basis. It will be about the liquid fabric of the human body. We study the composition of the blood, blood cells and their meaning.

Anatomy of the human cardiovascular system

The most important body forming this system is the heart. It is this muscular bag that plays a fundamental role in blood circulation in the body. Different blood vessels are departed from it in size and directions, which are divided into:

• veins;
• arteries;
• aortic;
• capillaries.

The listed structures carry out the constant circulation of the special tissue of the body - blood, which is washes all the cells, organs and systems as a whole. In humans (as in all mammals), two circle of blood circulation is distinguished: large and small, and such a system is called closed.

The main functions of its as follows:

• gas exchange - transportation (i.e., movements) oxygen and carbon dioxide;
• nutritious, or trophic - delivery of the necessary molecules from digestive organs to all tissues, systems, and so on;
• excretory - withdrawal of harmful and spent substances from all structures to excretory;
• delivery of the products of the endocrine system (hormones) to all organism cells;
• protective - participation in immune reactions through special antibodies.

Obviously, the functions are very significant. That is why it is so important the structure of blood cells, their role and in general characteristic. After all, blood is the basis of the activities of the entire relevant system.

The composition of the blood and the value of its cells

What is this red, with a specific taste and smell of a liquid that appears on any body area at the slightest injection?

By nature, blood is a type of connective tissue consisting of a liquid part - plasma and uniform elements of cells. Their percentage of approximately 60/40. In total, there are about 400 different compounds, both hormonal nature and vitamins, proteins, antibodies and trace elements.

The volume of this fluid in the organism of an adult is about 5.5-6 liters. Loss of 2-2.5 of them is deadly. Why? Because the blood performs a number of vital functions.

1. Provides organism homeostasis (constancy of the inner medium, including body temperature).
2. The operation of blood cells and plasma leads to distribution over all cells of important biologically active compounds: proteins, hormones, antibodies, nutrients, gases, vitamins, as well as exchange products.
3. Due to the constancy of blood composition, a certain level of acidity is maintained (pH should not exceed 7.4).
4. It is this tissue that takes care of the elimination of extra, harmful compounds from the organism through the excretory system and sweat glands.
5. Liquid solutions of electrolytes (salts) come out with urine, which is ensured by the work of blood and allocation organs.

Overestimate the value that have human blood cells is difficult. Consider in more detail the structure of each structural element of this important and unique biological fluid.

Plasma

The viscous liquid of yellowish color, which occupies up to 60% of the total blood mass. The composition is very diverse (several hundred substances and elements) and includes compounds from various chemical groups. So, this part of blood includes:

• Protein molecules. It is believed that each protein that exists in the body is present initially in the blood plasma. Especially many albumin and immunoglobulins playing an important role in protective mechanisms. About 500 names of plasma proteins are known.
• Chemical elements in the form of ions: sodium, chlorine, potassium, calcium, magnesium, iron, iodine, phosphorus, fluorine, manganese, selenium and others. There is almost the entire periodic Mendeleev system, about 80 items from it are in the blood plasma.
• Mono-, di- and polysaccharides.
• Vitamins and coenzymes.
• Hormones kidneys, adrenal glands, germ (adrenaline, endorphine, androgens, testosterone and others).
• Lipids (fats).
• Enzymes as biological catalysts.

The most important structural parts of the plasma are blood cells, which are 3 main varieties. They are the second component of this type of connective tissue, their structure and functions performed deserve separate attention.

Erythrocytes

The smallest cellular structures whose dimensions do not exceed 8 microns. However, their number is over 26 trillion! - makes you forget about the insignificant volumes of a separate particle.

Erythrocytes - blood cells that are devoid of conventional components of the structure. That is, they do not have neither the nucleus, nor EPS (endoplasmic network), nor chromosome, nor DNA and so on. If you compare this cell with something, then a biconuous porous disc is suitable - a peculiar sponge. The entire inner part, each time is filled with a specific molecule - hemoglobin. This protein, whose chemical basis is an iron atom. It is easily able to interact with oxygen and carbon dioxide, which is the main function of erythrocytes.

That is, red blood cells are simply filled with hemoglobin in the amount of 270 million per piece. Why red? Because it is this color that gives it an iron that makes up the basis of the protein, and due to the overwhelming majority of erythrocytes in the blood of a person, it acquires the corresponding color.

In appearance, when considering in a special microscope, red blood cells - rounded structures, as if flattened from the upper and lower parts to the center. Their predecessors are stem cells produced in the bone marrow and depot of the spleen.

Function

The role of erythrocytes is explained by the presence of hemoglobin. These structures collect oxygen in pulmonary alveols and distribute it to all cells, tissues, organs and systems. In this case, gas exchange is performed, because giving oxygen, they take carbon dioxide, which is also transported to the removal places - easy.

At various age, the activity of erythrocytes is not the same. For example, the fetal produces a special fetal hemoglobin, which carries out the transport of gas to an order more intense than the usual, characteristic of adults.

There is a common disease that provoke red blood cells. Blood cells produced in insufficient quantities lead to anemia - a serious disease of the overall weakening and thinning of the vitality of the body. After all, the normal supply of oxygen tissues is disturbed, which causes their starvation and, as a result, quick fatigue and weakness.

The life of each erythrocyte is from 90 to 100 days.

Thrombocytes

Another important human blood cells are platelets. These are flat structures whose sizes are 10 times less than red blood cells. Such minor volumes allow them to quickly accumulate and stick together to fulfill their direct destination.

As part of the body of these guards, there are about 1.5 trillion pieces, the amount is constantly updated and updated, as their life, alas, is very small - only about 9 days. Why guards order? This is due to the function they perform.

Value

Focusing in the cluster vascular space, blood cells thoroughly monitor the health and integrity of the organs. If suddenly somewhere arises the tissue rupture, they react immediately. Also sticking together, they seek the place of damage and restore the structure. In addition, it is in many ways the merit of blood coagulation on the wound. Therefore, their role is to ensure and restore the integrity of all vessels, covers, and so on.

Leukocytes

White blood cells that have received their name for absolute colorlessness. But the absence of painting does not significantly reduce their significance.

The rounded form of the Taurus is divided into several main species:

• eosinophils;
• neutrophils;
• monocytes;
• basophiles;
• lymphocytes.

The dimensions of these structures are sufficiently significant compared to erythrocytes and platelets. Reach 23 microns in diameter and live only a few hours (up to 36). Their functions vary depending on the variety.

White blood cells live not only in it. In fact, they only use fluid in order to get to the required destination and perform their functions. Leukocytes are in many organs and tissues. Therefore, specifically in the blood, their number is small.

Role in the body

The general value of all varieties of white Taurus is to protect against alien particles, microorganisms and molecules.

These are the main functions that perform leukocytes in the human body.

Stem cells

Life life that has blood cells is insignificant. Only some types of leukocytes responsible for memory can exist all their life. Therefore, the body functions a hematopoietic system consisting of two organs and ensuring the replenishment of all uniform elements.

These include:

• red bone marrow;
• spleen.

The bone marrow is especially important. It is located in the cavities of flat bones and produces absolutely all blood cells. Newborn children in this process take part and tubular education (shin, shoulder, brushes and feet). With age, such a brain remains only in pelvic bones, but it is enough to ensure the entire body formed blood elements.

Another body in which is not produced, but are intensified for emergency cases, quite volumetric amounts of blood taurus - spleen. This is a kind of "bloodstand" of each human body.

Why do stem cells need?

Blood stem cells are the most important undifferentiated formations that play a role in hemopoiesse - the formation of the tissue itself. Therefore, their normal functioning is the guarantee of the health and quality work of cardiovascular and all other systems.

In cases where a person loses a large amount of blood, which the brain itself cannot compensate or does not have time, the selection of donors is needed (it is also necessary in the case of blood renewal during leukemias). This complex process depends on the set of features, for example, on the degree of kinship and the comparability of people with each other by other indicators.

Norms of blood cells in medical analysis

For a healthy person there are certain norms of the number of shaped blood cells in the calculation of 1 mm 3. These indicators are as follows:

1. Erythrocytes - 3.5-5 million, hemoglobin protein - 120-155 g / l.
2. Platelets - 150-450 thousand
3. Leukocytes - from 2 to 5 thousand.

These indicators may vary depending on the age and human health. That is, blood is an indicator of the physical condition of people, so its timely analysis is the key to successful and high-quality treatment.