What red blood cells look like under a microscope. Human blood cells. The structure of blood cells. Sensitive ear hairs

Human blood is a liquid substance consisting of plasma and formed elements, or blood cells, suspended in it, which make up approximately 40-45% of the total volume. They are small in size and can only be seen under a microscope.

There are several types of blood cells that perform specific functions. Some of them function only within the circulatory system, others go beyond its boundaries. What they have in common is that they are all formed in the bone marrow from stem cells, the process of their formation is continuous, and their lifespan is limited.

All blood cells are divided into red and white. The first are erythrocytes, which make up the majority of all cells, the second are leukocytes.

Platelets are also considered to be blood cells. These small blood platelets are not actually full-fledged cells. They are small fragments separated from large cells - megakaryocytes.

Red blood cells are called red blood cells. This is the most numerous group of cells. They carry oxygen from the respiratory organs to the tissues and take part in the transport of carbon dioxide from the tissues to the lungs.

The place of formation of red blood cells is the red bone marrow. They live for 120 days and are destroyed in the spleen and liver.

They are formed from precursor cells - erythroblasts, which, before becoming an erythrocyte, go through different stages of development and divide several times. Thus, up to 64 red blood cells are formed from the erythroblast.

Red blood cells lack a nucleus and are shaped like a disk concave on both sides, the diameter of which is on average about 7-7.5 microns, and the thickness at the edges is 2.5 microns. This shape increases the ductility required for passage through small vessels and the surface area for gas diffusion. Old red blood cells lose their plasticity, which is why they linger in the small vessels of the spleen and are destroyed there.

Most red blood cells (up to 80%) have a biconcave spherical shape. The remaining 20% may have another: oval, cup-shaped, simple spherical, sickle-shaped, etc. Violation of the shape is associated with various diseases (anemia, deficiency of vitamin B 12, folic acid, iron, etc.).

Most of the cytoplasm of the red blood cell is occupied by hemoglobin, consisting of protein and heme iron, which gives the blood its red color. The non-protein part consists of four heme molecules with an Fe atom in each. It is thanks to hemoglobin that the red blood cell is able to carry oxygen and remove carbon dioxide. In the lungs, an iron atom binds with an oxygen molecule, hemoglobin turns into oxyhemoglobin, which gives the blood a scarlet color. In tissues, hemoglobin gives up oxygen and adds carbon dioxide, turning into carbohemoglobin, as a result the blood becomes dark. In the lungs, carbon dioxide is separated from hemoglobin and removed by the lungs to the outside, and the incoming oxygen is again associated with iron.

In addition to hemoglobin, the cytoplasm of the erythrocyte contains various enzymes (phosphatase, cholinesterase, carbonic anhydrase, etc.).

The erythrocyte membrane has a fairly simple structure compared to the membranes of other cells. It is an elastic thin mesh, which ensures rapid gas exchange.

On the surface of red blood cells there are different types of antigens that determine the Rh factor and blood group. The Rh factor can be positive or negative depending on the presence or absence of the Rh antigen. The blood group depends on which antigens are on the membrane: 0, A, B (the first group is 00, the second is 0A, the third is 0B, the fourth is AB).

In the blood of a healthy person, there may be small amounts of immature red blood cells called reticulocytes. Their number increases with significant blood loss, when replacement of red cells is required and the bone marrow does not have time to produce them, so it releases immature ones, which are nevertheless capable of performing the functions of red blood cells in transporting oxygen.

Leukocytes are white blood cells whose main task is to protect the body from internal and external enemies.

They are usually divided into granulocytes and agranulocytes. The first group is granular cells: neutrophils, basophils, eosinophils. The second group does not have granules in the cytoplasm; it includes lymphocytes and monocytes.

This is the most numerous group of leukocytes - up to 70% of the total number of white cells. Neutrophils got their name due to the fact that their granules are stained with dyes with a neutral reaction. Its grain size is fine, the granules have a purple-brownish tint.

The main task of neutrophils is phagocytosis, which consists in capturing pathogenic microbes and tissue breakdown products and destroying them inside the cell with the help of lysosomal enzymes found in granules. These granulocytes fight mainly bacteria and fungi and to a lesser extent viruses. Pus consists of neutrophils and their remains. Lysosomal enzymes are released during the breakdown of neutrophils and soften nearby tissues, thus forming a purulent focus.

A neutrophil is a rounded nuclear cell, reaching a diameter of 10 microns. The core may have the shape of a rod or consist of several segments (from three to five) connected by strands. An increase in the number of segments (up to 8-12 or more) indicates pathology. Thus, neutrophils can be band or segmented. The first are young cells, the second are mature. Cells with a segmented nucleus make up up to 65% of all leukocytes, and band cells in the blood of a healthy person make up no more than 5%.

The cytoplasm contains about 250 types of granules containing substances through which the neutrophil performs its functions. These are protein molecules that affect metabolic processes (enzymes), regulatory molecules that control the work of neutrophils, substances that destroy bacteria and other harmful agents.

These granulocytes are formed in the bone marrow from neutrophilic myeloblasts. A mature cell stays in the brain for 5 days, then enters the blood and lives here for up to 10 hours. From the vascular bed, neutrophils enter the tissues, where they remain for two to three days, then they enter the liver and spleen, where they are destroyed.

There are very few of these cells in the blood - no more than 1% of the total number of leukocytes. They have a round shape and a segmented or rod-shaped nucleus. Their diameter reaches 7-11 microns. Inside the cytoplasm there are dark purple granules of varying sizes. They got their name due to the fact that their granules are colored with dyes with an alkaline, or basic, reaction. Basophil granules contain enzymes and other substances involved in the development of inflammation.

Their main function is the release of histamine and heparin and participation in the formation of inflammatory and allergic reactions, including the immediate type (anaphylactic shock). In addition, they can reduce blood clotting.

They are formed in the bone marrow from basophilic myeloblasts. After maturation, they enter the blood, where they remain for about two days, then go into the tissues. What happens next is still unknown.

These granulocytes make up approximately 2-5% of the total number of white cells. Their granules are stained with an acidic dye, eosin.

They have a rounded shape and a slightly colored core, consisting of segments of the same size (usually two, less often three). Eosinophils reach 10-11 microns in diameter. Their cytoplasm is painted pale blue and is almost invisible among the large number of large round granules of yellow-red color.

These cells are formed in the bone marrow, their precursors are eosinophilic myeloblasts. Their granules contain enzymes, proteins and phospholipids. A mature eosinophil lives in the bone marrow for several days, after entering the blood it remains in it for up to 8 hours, then moves to tissues that have contact with the external environment (mucous membranes).

These are round cells with a large nucleus occupying most of the cytoplasm. Their diameter is 7 to 10 microns. The kernel can be round, oval or bean-shaped and has a rough structure. Consists of lumps of oxychromatin and basiromatin, resembling blocks. The core can be dark purple or light purple, sometimes it contains light inclusions in the form of nucleoli. The cytoplasm is colored light blue; around the nucleus it is lighter. In some lymphocytes, the cytoplasm has azurophilic granularity, which turns red when stained.

Two types of mature lymphocytes circulate in the blood:

Narrow plasma. They have a rough dark purple nucleus and a narrow blue rim of cytoplasm.
Wide-plasma. In this case, the kernel has a paler color and bean-shaped shape. The rim of the cytoplasm is quite wide, gray-blue in color, with rare ausurophilic granules.

From atypical lymphocytes in the blood you can find:

Small cells with barely visible cytoplasm and a pyknotic nucleus.
Cells with vacuoles in the cytoplasm or nucleus.
Cells with lobed, kidney-shaped, jagged nuclei.
Bare kernels.

Lymphocytes are formed in the bone marrow from lymphoblasts and undergo several stages of division during the process of maturation. Its complete maturation occurs in the thymus, lymph nodes and spleen. Lymphocytes are immune cells that mediate immune responses. There are T-lymphocytes (80% of the total) and B-lymphocytes (20%). The former matured in the thymus, the latter in the spleen and lymph nodes. B lymphocytes are larger in size than T lymphocytes. The lifespan of these leukocytes is up to 90 days. Blood for them is a transport medium through which they enter tissues where their help is required.

The actions of T-lymphocytes and B-lymphocytes are different, although both take part in the formation of immune reactions.

The former are engaged in the destruction of harmful agents, usually viruses, through phagocytosis. The immune reactions in which they participate are nonspecific resistance, since the actions of T lymphocytes are the same for all harmful agents.

Based on the actions they perform, T-lymphocytes are divided into three types:

T-helpers. Their main task is to help B-lymphocytes, but in some cases they can act as killers.
T-killers. Destroy harmful agents: foreign, cancerous and mutated cells, infectious agents.
T-suppressors. Inhibit or block overly active reactions of B-lymphocytes.

B-lymphocytes act differently: against pathogens they produce antibodies - immunoglobulins. This happens as follows: in response to the actions of harmful agents, they interact with monocytes and T-lymphocytes and turn into plasma cells that produce antibodies that recognize the corresponding antigens and bind them. For each type of microbe, these proteins are specific and are capable of destroying only a certain type, therefore the resistance that these lymphocytes form is specific, and it is directed primarily against bacteria.

These cells provide the body's resistance to certain harmful microorganisms, which is commonly called immunity. That is, having encountered a harmful agent, B-lymphocytes create memory cells that form this resistance. The same thing - the formation of memory cells - is achieved by vaccinations against infectious diseases. In this case, a weak microbe is introduced so that the person can easily survive the disease, and as a result, memory cells are formed. They can remain for life or for a certain period, after which the vaccination must be repeated.

Monocytes are the largest of the leukocytes. Their number ranges from 2 to 9% of all white blood cells. Their diameter reaches 20 microns. The monocyte nucleus is large, occupies almost the entire cytoplasm, can be round, bean-shaped, mushroom-shaped, or butterfly-shaped. When stained it turns red-violet. The cytoplasm is smoky, bluish-smoky, less often blue. It usually has an azurophilic fine grain size. It may contain vacuoles (voids), pigment grains, and phagocytosed cells.

Monocytes are produced in the bone marrow from monoblasts. After maturation, they immediately appear in the blood and remain there for up to 4 days. Some of these leukocytes die, some move into the tissue, where they mature and turn into macrophages. These are the largest cells with a large round or oval nucleus, blue cytoplasm and a large number of vacuoles, which is why they appear foamy. The lifespan of macrophages is several months. They can be constantly in one place (resident cells) or move (wandering).

Monocytes form regulatory molecules and enzymes. They are able to form an inflammatory response, but can also inhibit it. In addition, they participate in the wound healing process, helping to speed it up, and promote the restoration of nerve fibers and bone tissue. Their main function is phagocytosis. Monocytes destroy harmful bacteria and inhibit the proliferation of viruses. They are able to carry out commands, but cannot distinguish between specific antigens.

These blood cells are small, anucleate plates and can be round or oval in shape. During activation, when they are near the damaged vessel wall, they form outgrowths, so they look like stars. Platelets contain microtubules, mitochondria, ribosomes, and specific granules containing substances necessary for blood clotting. These cells are equipped with a three-layer membrane.

Platelets are produced in the bone marrow, but in a completely different way than other cells. Blood plates are formed from the largest cells of the brain - megakaryocytes, which, in turn, were formed from megakaryoblasts. Megakaryocytes have a very large cytoplasm. After the cell matures, membranes appear in it, dividing it into fragments that begin to separate, and thus platelets appear. They leave the bone marrow into the blood, stay in it for 8-10 days, then die in the spleen, lungs, and liver.

Blood plates can have different sizes:

the smallest are microforms, their diameter does not exceed 1.5 microns;
normoforms reach 2-4 microns;
macroforms – 5 microns;
megaloforms – 6-10 microns.

Platelets perform a very important function - they participate in the formation of a blood clot, which closes the damage in the vessel, thereby preventing blood from leaking out. In addition, they maintain the integrity of the vessel wall and promote its rapid recovery after damage. When bleeding begins, platelets adhere to the edge of the injury until the hole is completely closed. The adhered plates begin to break down and release enzymes that act on. As a result, insoluble fibrin threads are formed, tightly covering the injury site.

Conclusion

Blood cells have a complex structure, and each type performs a specific job: from transporting gases and substances to producing antibodies against foreign microorganisms. Their properties and functions have not been fully studied to date. For normal human life, a certain amount of each type of cell is necessary. Based on their quantitative and qualitative changes, doctors have the opportunity to suspect the development of pathologies. The composition of the blood is the first thing that a doctor studies when treating a patient.

Human blood consists of cells and a liquid part, or serum. The liquid part is a solution that contains a certain amount of micro- and macroelements, fats, carbohydrates and proteins. Blood cells are usually divided into three main groups, each of which has its own structural features and functions. Let's take a closer look at each of them.

Erythrocytes, or red blood cells

Red blood cells are fairly large cells that have a very characteristic biconcave disc shape. Red cells do not contain a nucleus; in its place is a hemoglobin molecule. Hemoglobin is a rather complex compound that consists of a protein part and a divalent iron atom. Red blood cells are formed in the bone marrow.

Red blood cells have many functions:

Gas exchange is one of the main functions of blood. Hemoglobin is directly involved in this process. In the small pulmonary vessels, the blood is saturated with oxygen, which combines with the iron of hemoglobin. This connection is reversible, so oxygen remains in those tissues and cells where it is needed. At the same time, when one atom of oxygen is lost, hemoglobin combines with carbon dioxide, which is transferred to the lungs and released into the environment.
In addition, on the surface of red blood cells there are specific polysaccharide molecules, or antigens, that determine the Rh factor and blood type.

White blood cells, or leukocytes

Leukocytes are a fairly large group of different cells, the main function of which is to protect the body from infections, toxins and foreign bodies. These cells have a nucleus, can change their shape and pass through tissue. Formed in the bone marrow. Leukocytes are usually divided into several separate types:

Neutrophils are a large group of leukocytes that have the ability to phagocytose. Their cytoplasm contains many granules filled with enzymes and biologically active substances. When bacteria or viruses enter the body, the neutrophil moves to the foreign cell, captures it and destroys it.
Eosinophils are blood cells that perform a protective function by destroying pathogenic organisms through phagocytosis. They work in the mucous membrane of the respiratory tract, intestines and urinary system.
Basophils are a small group of small oval cells that take part in the development of the inflammatory process and anaphylactic shock.
Macrophages are cells that actively destroy viral particles but have accumulations of granules in the cytoplasm.
Monocytes are characterized by a specific function, as they can either develop or, conversely, inhibit the inflammatory process.
Lymphocytes are white blood cells responsible for the immune response. Their peculiarity lies in the ability to form resistance to those microorganisms that have already penetrated the human blood at least once.

Blood platelets, or platelets

Platelets are small, oval or round shaped human blood cells. After activation, protrusions form on the outer one, causing it to resemble a star.

Platelets perform a number of quite important functions. Their main purpose is to form a so-called blood clot. The first to arrive at the site of injury are platelets, which, under the influence of enzymes and hormones, begin to stick together, forming a blood clot. This clot seals the wound and stops bleeding. In addition, these blood cells are responsible for the integrity and stability of the vascular walls.

We can say that blood is a rather complex and multifunctional type of connective tissue designed to maintain normal life functions.

Cancer cells develop from healthy particles in the body. They do not penetrate tissues and organs from the outside, but are part of them.

Under the influence of factors that have not been fully studied, malignant formations stop responding to signals and begin to behave differently. The appearance of the cell also changes.

A malignant tumor is formed from a single cell that has become cancerous. This happens due to modifications occurring in genes. Most malignant particles have 60 or more mutations.

Before the final transformation into a cancer cell, it goes through a series of transformations. As a result, some of the pathological cells die, but a few survive and become cancerous.

When a normal cell mutates, it goes into the stage of hyperplasia, then atypical hyperplasia, and turns into carcinoma. Over time, it becomes invasive, that is, it moves throughout the body.

What is a healthy particle

It is generally accepted that cells are the first step in the organization of all living organisms. They are responsible for ensuring all vital functions, such as growth, metabolism, and transmission of biological information. In the literature they are usually called somatic, that is, those that make up the entire human body, except for those that take part in sexual reproduction.

The particles that make up a person are very diverse. However, they share a number of common features. All healthy elements go through the same stages of their life journey. It all starts at birth, then the process of maturation and functioning occurs. It ends with the death of the particle as a result of the activation of a genetic mechanism.

The process of self-destruction is called apoptosis, it occurs without disturbing the viability of surrounding tissues and inflammatory reactions.

During their life cycle, healthy particles divide a certain number of times, that is, they begin to reproduce only if there is a need. This happens after receiving a signal to divide. There is no division limit in reproductive and stem cells and lymphocytes.

Five interesting facts

Malignant particles are formed from healthy tissue. As they develop, they begin to differ significantly from ordinary cells.

Scientists were able to identify the main features of tumor-forming particles:

Endlessly divisible– the pathological cell constantly doubles and increases in size. Over time, this leads to the formation of a tumor consisting of a huge number of copies of the cancer particle.
Cells separate from each other and exist autonomously– they lose their molecular connection with each other and stop sticking together. This leads to the movement of malignant elements throughout the body and their settling on various organs.
Can't manage its life cycle– p53 protein is responsible for cell restoration. In most cancer cells, this protein is faulty, so life cycle control is not established. Experts call this defect immortality.
Lack of development– malignant elements lose their signal with the body and engage in endless division without having time to mature. Because of this, multiple gene errors are formed in them, affecting their functional abilities.
Each cell has different external parameters– pathological elements are formed from various healthy parts of the body, which have their own characteristics in appearance. Therefore, they differ in size and shape.

There are malignant elements that do not form a lump, but accumulate in the blood. An example is leukemia. Cancer cells get more and more errors as they divide. This leads to the fact that subsequent elements of the tumor may be completely different from the initial pathological particle.

Many experts believe that cancer particles begin to move inside the body immediately after the formation of a tumor. To do this, they use blood and lymphatic vessels. Most of them die as a result of the immune system, but a few survive and settle on healthy tissues.

All detailed information about cancer cells in this scientific lecture:

The structure of a malignant particle

Disturbances in genes lead not only to changes in the functioning of cells, but also to disorganization of their structure. They change in size, internal structure, and the shape of the complete set of chromosomes. These visible abnormalities allow specialists to distinguish them from healthy particles. Examining cells under a microscope allows cancer to be diagnosed.

Core

Tens of thousands of genes are located in the nucleus. They control the functioning of the cell, dictating its behavior. Most often, the nuclei are located in the central part, but in some cases they can move to one side of the membrane.

In cancer cells, the nuclei vary the most; they become larger and acquire a spongy structure. The nuclei have depressed segments, a rugged membrane, and enlarged and distorted nucleoli.

Proteins

The Protein Challenge in performing basic functions that are necessary to maintain cell viability. They transport nutrients to it, convert them into energy, and transmit information about changes in the external environment. Some proteins are enzymes whose job is to convert unused substances into needed products.

In a cancer cell, proteins change and they lose the ability to do their job correctly. Errors affect enzymes and the particle's life cycle is altered.

Mitochondria

The part of the cell in which products such as proteins, sugars, and lipids are converted into energy is called mitochondria. This transformation uses oxygen. As a result, toxic wastes such as free radicals are formed. It is believed that they can trigger the process of turning a cell into a cancerous one.

Plasma membrane

All elements of the particle are surrounded by a wall made of lipids and proteins. The membrane's job is to keep them all in place. In addition, it blocks the path of those substances that should not enter the cell from the body.

Special membrane proteins, which are its receptors, perform an important function. They transmit coded messages to the cell, according to which it reacts to changes in the environment.

Misreading of genes leads to changes in receptor production. Because of this, the particle does not become aware of changes in the external environment and begins to lead an autonomous way of existence. This behavior leads to cancer.

Malignant particles of different organs

Cancer cells can be recognized by their shape. Not only do they behave differently, but they also look different from normal ones.

Scientists from Clarkson University conducted research which resulted in the conclusion that healthy and pathological particles differ in geometric shape. For example, malignant cervical cancer cells have a higher degree of fractality.

Fractal are geometric shapes that consist of similar parts. Each of them looks like a copy of the entire figure.

Scientists were able to obtain images of cancer cells using an atomic force microscope. The device made it possible to obtain a three-dimensional map of the surface of the particle being studied.

Scientists continue to study changes in fractality during the process of converting normal particles into cancer particles.

Lungs' cancer

Lung pathology can be non-small cell or small cell. In the first case, tumor particles divide slowly; in later stages, they are pinched off from the maternal lesion and move throughout the body due to the flow of lymph.

In the second case, the neoplasm particles are small in size and prone to rapid division. Over the course of a month, the number of cancer particles doubles. Elements of the tumor can spread both to organs and bone tissue.

The cell has an irregular shape with rounded areas. Multiple growths of different structures are visible on the surface. The color of the cell at the edges is beige, and towards the middle it turns red.

Breast cancer

Tumor formation in the breast may consist of particles that have been transformed from components such as connective and glandular tissue, ducts. The tumor elements themselves can be large or small. In highly differentiated breast pathology, the particles are distinguished by nuclei of the same size.

The cell has a round shape, its surface is loose and heterogeneous. Long straight shoots protrude from it in all directions. At the edges the color of the cancer cell is lighter and brighter, but inside it is darker and more saturated.

Skin cancer

Skin cancer is most often associated with the transformation of melanocytes into a malignant form. The cells are located in the skin in any part of the body. Experts often associate these pathological changes with prolonged exposure to the open sun or in a solarium. Ultraviolet radiation promotes the mutation of healthy skin elements.

Cancer cells develop on the surface of the skin for a long time. In some cases, pathological particles behave more aggressively, quickly growing deep into the skin.

Oncology cell It has a rounded shape, with multiple villi visible across its entire surface. Their color is lighter than that of the membrane.

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They are small in size and can only be seen under a microscope.

All blood cells are divided into red and white. The first are erythrocytes, which make up the majority of all cells, the second are leukocytes.

Platelets are also considered to be blood cells. These small blood platelets are not actually full-fledged cells. They are small fragments separated from large cells - megakaryocytes.

Red blood cells

The place of formation of red blood cells is the red bone marrow. They live for 120 days and are destroyed in the spleen and liver.

In addition to hemoglobin, the cytoplasm of the erythrocyte contains various enzymes (phosphatase, cholinesterase, carbonic anhydrase, etc.).

The erythrocyte membrane has a fairly simple structure compared to the membranes of other cells. It is an elastic thin mesh, which ensures rapid gas exchange.

Leukocytes

Leukocytes are white blood cells whose main task is to protect the body from internal and external enemies.

Neutrophils

The main task of neutrophils is phagocytosis, which consists of capturing pathogenic microbes and tissue breakdown products and destroying them inside the cell with the help of lysosomal enzymes found in granules. These granulocytes fight mainly bacteria and fungi and to a lesser extent viruses. Pus consists of neutrophils and their remains. Lysosomal enzymes are released during the breakdown of neutrophils and soften nearby tissues, thus forming a purulent focus.

Basophils

Eosinophils

These granulocytes make up approximately 2-5% of the total number of white cells. Their granules are stained with an acidic dye, eosin.

They have a rounded shape and a slightly colored core, consisting of segments of the same size (usually two, less often three). Eosinophils reach µm in diameter. Their cytoplasm is painted pale blue and is almost invisible among the large number of large round granules of yellow-red color.

Two types of mature lymphocytes circulate in the blood:

Narrow plasma. They have a rough dark purple nucleus and a narrow blue rim of cytoplasm.
Wide-plasma. In this case, the kernel has a paler color and bean-shaped shape. The rim of the cytoplasm is quite wide, gray-blue in color, with rare ausurophilic granules.

From atypical lymphocytes in the blood you can find:

Small cells with barely visible cytoplasm and a pyknotic nucleus.
Cells with vacuoles in the cytoplasm or nucleus.
Cells with lobed, kidney-shaped, jagged nuclei.
Bare kernels.

The actions of T-lymphocytes and B-lymphocytes are different, although both take part in the formation of immune reactions.

Based on the actions they perform, T-lymphocytes are divided into three types:

T-helpers. Their main task is to help B-lymphocytes, but in some cases they can act as killers.
T-killers. Destroy harmful agents: foreign, cancerous and mutated cells, infectious agents.
T-suppressors. Inhibit or block overly active reactions of B-lymphocytes.

Monocytes

Platelets

Blood plates can have different sizes:

the smallest are microforms, their diameter does not exceed 1.5 microns;
normoforms reach 2-4 microns;
macroforms – 5 microns;
megaloforms – 6-10 microns.

Platelets perform a very important function - they participate in the formation of a blood clot, which closes the damage in the vessel, thereby preventing blood from leaking out. In addition, they maintain the integrity of the vessel wall and promote its rapid recovery after damage. When bleeding begins, platelets adhere to the edge of the injury until the hole is completely closed. The adhered plates begin to break down and release enzymes that affect the blood plasma. As a result, insoluble fibrin threads are formed, tightly covering the injury site.

Conclusion

Human blood cells. The structure of blood cells

In the anatomical structure of the human body, there are cells, tissues, organs and organ systems that carry out all vital functions. There are about 11 such systems in total:

nervous (CNS);
digestive;
cardiovascular;
hematopoietic;
respiratory;
musculoskeletal;
lymphatic;
endocrine;
excretory;
sexual;
musculocutaneous.

Each of them has its own characteristics, structure and performs certain functions. We will consider that part of the circulatory system that is its basis. We will talk about the liquid tissue of the human body. Let's study the composition of blood, blood cells and their significance.

Anatomy of the human cardiovascular system

The most important organ that forms this system is the heart. It is this muscle pouch that plays a fundamental role in blood circulation throughout the body. Blood vessels of different sizes and directions depart from it, which are divided into:

veins;
arteries;
aorta;
capillaries.

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

Its main functions are as follows:

gas exchange - the transport (that is, movement) of oxygen and carbon dioxide;
nutritional, or trophic - delivery of necessary molecules from the digestive organs to all tissues, systems, and so on;
excretory - removal of harmful and waste substances from all structures to the excretory;
delivery of endocrine system products (hormones) to all cells of the body;
protective - participation in immune reactions through special antibodies.

Obviously the functions are very significant. This is why the structure of blood cells, their role and general characteristics are so important. After all, blood is the basis for the activity of the entire corresponding system.

Composition of blood and the significance of its cells

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

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

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

Provides homeostasis of the body (constancy of the internal environment, including body temperature).
The work of blood and plasma cells leads to the distribution of important biologically active compounds throughout all cells: proteins, hormones, antibodies, nutrients, gases, vitamins, as well as metabolic products.
Due to the constant composition of the blood, a certain level of acidity is maintained (pH should not exceed 7.4).
It is this tissue that takes care of removing excess, harmful compounds from the body through the excretory system and sweat glands.
Liquid solutions of electrolytes (salts) are excreted in the urine, which is ensured solely by the work of the blood and excretory organs.

It is difficult to overestimate the importance of human blood cells. Let us consider in more detail the structure of each structural element of this important and unique biological fluid.

Plasma

A viscous liquid of a yellowish color, occupying 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 the blood includes:

Protein molecules. It is believed that every protein that exists in the body is initially present in the blood plasma. There are especially many albumins and immunoglobulins, which play an important role in protective mechanisms. In total, 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. Almost the entire Mendeleev Periodic System is present here, approximately 80 items from it are found in the blood plasma.
Mono-, di- and polysaccharides.
Vitamins and coenzymes.
Hormones of the kidneys, adrenal glands, gonads (adrenaline, endorphin, androgens, testosterones and others).
Lipids (fats).
Enzymes as biological catalysts.

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

Red blood cells

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

Red blood cells are blood cells that are structures devoid of the usual constituent parts. That is, they have no nucleus, no EPS (endoplasmic reticulum), no chromosomes, no DNA, and so on. If you compare this cell with anything, then a biconcave porous disk - a kind of sponge - is best suited. The entire internal part, each pore, is filled with a specific molecule - hemoglobin. This is a 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 red blood cells.

That is, red blood cells are simply filled with hemoglobin in the amount of 270 million per cell. Why red? Because it is precisely this color that gives them iron, which forms the basis of protein, and due to the overwhelming majority of red blood cells in human blood, it acquires the corresponding color.

In appearance, when viewed through a special microscope, red blood cells are rounded structures, seemingly flattened from the top and bottom to the center. Their precursors are stem cells produced in the bone marrow and spleen depot.

Function

The role of red blood cells is explained by the presence of hemoglobin. These structures collect oxygen in the pulmonary alveoli and distribute it to all cells, tissues, organs and systems. At the same time, gas exchange occurs, because by giving up oxygen, they take away carbon dioxide, which is also transported to the places of excretion - the lungs.

At different ages, the activity of red blood cells is not the same. For example, the fetus produces special fetal hemoglobin, which transports gases an order of magnitude more intensively than the usual one characteristic of adults.

There is a common disease that is caused by red blood cells. Blood cells produced in insufficient quantities lead to anemia - a serious disease of general weakening and thinning of the body's vital forces. After all, the normal supply of oxygen to tissues is disrupted, which causes their starvation and, as a result, rapid fatigue and weakness.

The lifespan of each red blood cell is from 90 to 100 days.

Platelets

Another important human blood cell is platelets. These are flat structures, the size of which is 10 times smaller than red blood cells. Such small volumes allow them to quickly accumulate and stick together to fulfill their intended purpose.

There are about 1.5 trillion of these guardians of order in the body, the number is constantly replenished and renewed, since their lifespan, alas, is very short - only about 9 days. Why law enforcement officers? This is due to the function they perform.

Meaning

Orienting themselves in the parietal vascular space, blood cells, platelets, carefully monitor the health and integrity of organs. If suddenly a tissue rupture occurs somewhere, they react immediately. By sticking together, they seem to seal the damaged area and restore the structure. In addition, they are largely responsible for blood clotting on the wound. Therefore, their role is precisely to ensure and restore the integrity of all vessels, integuments, and so on.

Leukocytes

White blood cells, which got their name for their absolute colorlessness. But the lack of coloring does not in any way diminish their significance.

Round-shaped bodies are divided into several main types:

The sizes of these structures are quite significant compared to erythrocytes and platelets. They 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 liquid to get to the required destination and perform their functions. Leukocytes are found in many organs and tissues. Therefore, their specific amount in the blood is small.

Role in the body

The general significance of all varieties of white bodies is to provide protection against foreign particles, microorganisms and molecules.

These are the main functions that white blood cells perform in the human body.

Stem cells

The lifespan of blood cells is insignificant. Only some types of leukocytes responsible for memory can exist throughout life. Therefore, the body has a hematopoietic system, consisting of two organs and ensuring the replenishment of all formed elements.

These include:

Bone marrow is especially important. It is located in the cavities of flat bones and produces absolutely all blood cells. In newborns, tubular formations (lower leg, shoulder, hands and feet) also take part in this process. With age, such brain remains only in the pelvic bones, but it is enough to provide the entire body with formed blood elements.

Another organ that does not produce, but stores quite large quantities of blood cells for emergencies, is the spleen. This is a kind of “blood depot” of every human body.

Why are stem cells needed?

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

In cases where a person loses a large amount of blood, which the brain itself cannot or does not have time to replenish, selection of donors is necessary (this is also necessary in the case of blood renewal in leukemia). This process is complex and depends on many features, for example, on the degree of relationship and the comparability of people with each other in other respects.

Blood cell norms in medical analysis

For a healthy person, there are certain norms for the amount of formed blood elements per 1 mm 3 . These indicators are as follows:

Red blood cells - 3.5-5 million, protein hemoglobin g/l.
Thrombocytes thousand
Leukocytes - from 2 to 5 thousand.

These rates may vary depending on the person's age and 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.

Blood under a microscope and human blood groups

Since ancient times, human blood has been endowed with mystical properties. People made sacrifices to the gods with the obligatory ritual of bloodletting. Sacred vows were sealed with the touch of freshly cut wounds. A wooden idol “crying” with blood was the last argument of the priests in an attempt to convince their fellow tribesmen of something. The ancient Greeks considered blood to be the guardian of the properties of the human soul.

Modern science has penetrated many of the mysteries of blood, but research continues to this day. Medicine, immunology, gene geography, biochemistry, and genetics study the biophysical and chemical properties of blood in a complex manner. Today we know what human blood groups are. The optimal blood composition of a person adhering to a healthy lifestyle has been calculated. It has been revealed that a person’s blood sugar level varies depending on his physical and mental state. Scientists have found the answer to the question “how much blood is there in a person and what is the speed of blood flow?” not out of idle curiosity, but for the purpose of diagnosing and treating cardiovascular and other diseases.

The microscope has long become an indispensable human assistant in many areas. Through the lens of the device you can see what is not visible to the naked eye. An interesting object for research is blood. Under a microscope, you can examine the main elements of human blood composition: plasma and formed elements.

For the first time, the composition of human blood was studied by an Italian doctor, Marcello Malpighi. He mistook the formed elements floating in the plasma for fat globules. Blood cells have more than once been called either balloons or animals, mistaking them for intelligent beings. The term “blood cells” or “blood globules” was introduced into scientific use by Anthony Leeuwenhoek. Blood under a microscope is a kind of mirror of the state of the human body. With one drop you can determine what is bothering a person at the moment. Hematology, or the science that studies blood, hematopoiesis and specific diseases, is today experiencing a boom in its development. Thanks to the study of blood, new high-tech methods for diagnosing diseases and their treatment are being introduced into medical practice.

Blood of a sick person

Blood of a healthy person

Blood of a healthy person (electron microscope)

You too can join the world of science with the help of Altami optical instruments. Histological microslides for examination under a microscope, which include blood samples, can be prepared at home without special processing. To do this, you should wash and degrease the slides on which you will place a drop of blood. Using another slide or spatula, quickly spread the liquid into a thin layer. For home experiments, the use of special dyes is unnecessary. Dry the preparation in air until the shine disappears and fix it on the stage, first placing a cover glass on top. The temporary biological product is usable for only a few hours, but it will be enough to unravel the mysteries of the blood with our hint.

By the way, in order to see what is included in a person’s blood, it is not at all necessary to cut a finger. It is enough to use ready-made Altami microslides.

So, if we look at blood under a microscope, under high magnification, we will see that it contains many different cells. Today it is known that blood in the human body is a type of connective tissue. It consists of the liquid part of the plasma and the formed elements suspended in it: red blood cells, leukocytes and platelets. Blood cells are produced in the red bone marrow. Interestingly, in a child, the entire bone marrow is red, while in an adult, blood is produced only in certain bones.

Pay attention to the pink flattened balls - red blood cells. They transport molecules of the hemoglobin protein, which gives red blood cells their delicate tint. With the help of protein, red blood cells enrich every cell of the human body with oxygen and remove carbon dioxide. If a person drinks a little water, the red blood cells stick together and do not tolerate hemoglobin well. In certain diseases, an insufficient number of red blood cells is produced, which leads to oxygen starvation of tissues. If the blood is infected with a fungus, these blood cells will resemble gears or be shaped like curved hooks.

Blood clotting (electron microscope)

It is well known that there are different human blood groups and Rh factor, positive or negative. It is red blood cells that make it possible to assign a person’s blood to a particular group and Rhesus affiliation. The various reactions identified between the red blood cells of one person and the blood plasma of another made it possible to systematize blood by groups and rhesus. The development of a blood compatibility table is on a par with such a great discovery as Mendeleev’s periodic table of chemical elements.

Today, the blood type is determined in the first days of a newborn’s life. Like fingerprints, a person's blood types remain the same throughout life. Back in 1900, the world did not know what blood types were. A person who required a blood transfusion was given the procedure without realizing that his blood might be incompatible with the donor's blood. Austrian immunologist, Nobel laureate Karl Landsteiner initiated the classification of liquid connective tissue and discovered the Rhesus system. The blood compatibility table acquired its final form thanks to the research of the Czech doctor Jacob Jansky.

Blood leukocytes are represented by several types of cells. Neutrophils or granulocytes are cells inside which there is a nucleus of several parts. Fine granules are scattered around large cells. Lymphocytes have a smaller round nucleus, but it occupies almost the entire cell. The bean-shaped nucleus is characteristic of monocytes.

Erythrocytes or red blood cells (electron microscope)

Erythrocytes or red blood cells

Leukocytes protect us from infections and diseases, including such dangerous ones as cancer. At the same time, the functions of warrior cells are strictly delimited. If T lymphocytes recognize and remember what different microbes look like, then B lymphocytes produce antibodies against them. Neutrophils “devour” substances foreign to the body. In the struggle for human health, both microbes and lymphocytes die. Increased volume of leukocytes indicates the presence of an inflammatory process in the body.

Blood platelets or platelets are responsible for creating dense blood clots that stop minor bleeding. Platelets do not have a cell nucleus and are clusters of small granular cells with a rough shell. As a rule, platelets “walk in formation”, in quantities from 3 to 10 pieces.

The liquid part of the blood is called plasma. Red blood cells, white blood cells and platelets, together with plasma, make up an important component of the blood system - peripheral blood. You are already tormented by the question: “how much blood is there in a person?” Then you will be interested to know that the total amount of blood in an adult body is 6–8% of body weight, and in a child’s body – 8–9%. Now you can calculate how much blood is in a person, knowing his weight.

In addition to blood cells, plasma contains proteins and minerals in the form of ions. Under the lens of the Altami microscope, other inclusions are visible, harmful, which should not be in the blood of a healthy person. Thus, uric acid salts are presented in the form of crystals resembling glass fragments. Crystals mechanically damage blood cells and tear off the film from the walls of blood vessels. Cholesterol looks like flakes that settle on the walls of the blood vessel and gradually narrow its lumen. The presence of bacteria and fungi of various irregular shapes indicates serious disorders of the human immune system.

Leukocytes or white blood cells (electron microscope)

Macrophages destroy foreign elements. They are good.

You can find irregularly shaped crystalloids in the blood - this is sugar, the excess of which leads to metabolic disorders. The level of sugar in human blood is the most important indicator in a clinical blood test. You can avoid diseases such as diabetes mellitus, some diseases of the central nervous system, hypertension, atherosclerosis and others if you take a blood glucose test once a year. A person’s blood sugar level, whether high or low, directly indicates a predisposition to a particular disease.

Thanks to the most exciting activity - examining a drop of blood under an Altami microscope - you have made a journey into the world of hematology: you have learned about the composition of blood and the important role it plays in the human body.

They are small in size and can only be seen under a microscope.

All blood cells are divided into red and white. The first are erythrocytes, which make up the majority of all cells, the second are leukocytes.

Platelets are also considered to be blood cells. These small blood platelets are not actually full-fledged cells. They are small fragments separated from large cells - megakaryocytes.

Red blood cells

The place of formation of red blood cells is the red bone marrow. They live for 120 days and are destroyed in the spleen and liver.

Most of the cytoplasm of the red blood cell is occupied by hemoglobin, consisting of protein and heme iron, which gives the blood its red color. The non-protein part consists of four heme molecules with an Fe atom in each. It is thanks to hemoglobin that the red blood cell is able to carry oxygen and remove carbon dioxide. In the lungs, an iron atom binds with an oxygen molecule, hemoglobin turns into oxyhemoglobin, which gives the blood a scarlet color. In tissues, hemoglobin gives up oxygen and adds carbon dioxide, turning into carbohemoglobin, as a result the blood becomes dark. In the lungs, carbon dioxide is separated from hemoglobin and removed by the lungs to the outside, and the incoming oxygen is again associated with iron.

In addition to hemoglobin, the cytoplasm of the erythrocyte contains various enzymes (phosphatase, cholinesterase, carbonic anhydrase, etc.).

The erythrocyte membrane has a fairly simple structure compared to the membranes of other cells. It is an elastic thin mesh, which ensures rapid gas exchange.

Leukocytes

Leukocytes are white blood cells whose main task is to protect the body from internal and external enemies.

Neutrophils

Basophils

Eosinophils

These granulocytes make up approximately 2-5% of the total number of white cells. Their granules are stained with an acidic dye, eosin.

Lymphocytes

Two types of mature lymphocytes circulate in the blood:

Narrow plasma. They have a rough dark purple nucleus and a narrow blue rim of cytoplasm.
Wide-plasma. In this case, the kernel has a paler color and bean-shaped shape. The rim of the cytoplasm is quite wide, gray-blue in color, with rare ausurophilic granules.

From atypical lymphocytes in the blood you can find:

Small cells with barely visible cytoplasm and a pyknotic nucleus.
Cells with vacuoles in the cytoplasm or nucleus.
Cells with lobed, kidney-shaped, jagged nuclei.
Bare kernels.

The actions of T-lymphocytes and B-lymphocytes are different, although both take part in the formation of immune reactions.

Based on the actions they perform, T-lymphocytes are divided into three types:

T-helpers. Their main task is to help B-lymphocytes, but in some cases they can act as killers.
T-killers. Destroy harmful agents: foreign, cancerous and mutated cells, infectious agents.
T-suppressors. Inhibit or block overly active reactions of B-lymphocytes.

Monocytes

Platelets

Blood plates can have different sizes:

the smallest are microforms, their diameter does not exceed 1.5 microns;
normoforms reach 2-4 microns;
macroforms – 5 microns;
megaloforms – 6-10 microns.

Platelets perform a very important function - they participate in the formation of a blood clot, which closes the damage in the vessel, thereby preventing blood from leaking out. In addition, they maintain the integrity of the vessel wall and promote its rapid recovery after damage. When bleeding begins, platelets adhere to the edge of the injury until the hole is completely closed. The adhered plates begin to break down and release enzymes that affect the blood plasma. As a result, insoluble fibrin threads are formed, tightly covering the injury site.

Conclusion

Blood under a microscope and human blood groups

Blood of a sick person

Blood of a healthy person

Blood of a healthy person (electron microscope)

You too can join the world of science with the help of Altami optical instruments. Histological microslides for examination under a microscope, which include blood samples, can be prepared at home without special processing. To do this, you should wash and degrease the slides on which you will place a drop of blood. Using another slide or spatula, quickly spread the liquid into a thin layer. For home experiments, the use of special dyes is unnecessary. Dry the preparation in air until the shine disappears and fix it on the stage, first placing a cover glass on top. The temporary biological product is usable for only a few hours, but it will be enough to unravel the mysteries of the blood with our hint.

By the way, in order to see what is included in a person’s blood, it is not at all necessary to cut a finger. It is enough to use ready-made Altami microslides.

Blood clotting (electron microscope)

Erythrocytes or red blood cells (electron microscope)

Erythrocytes or red blood cells

Leukocytes or white blood cells (electron microscope)

Macrophages destroy foreign elements. They are good.

Comments (3)

I was looking for answers for my child, but when I read it, I learned a lot of new things myself. Thank you very much for the article, good luck. 😉

Thanks for the interesting article. Please tell me what magnification of a microscope is needed to view blood?

I looked at my blood under x40 magnification, it turns out that I am a sick person(

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Human blood cells - functions where they are formed and destroyed

Blood is the most important system in the human body, performing many different functions. Blood is a transport system through which vital substances are transported to the organs and waste substances, decay products and other elements that must be eliminated from the body are removed from the cells. The blood also circulates substances and cells that provide protection to the body as a whole.

Blood consists of cells and a liquid part - serum, consisting of proteins, fats, sugars and trace elements.

There are three main types of cells in the blood:

Red blood cells are cells that transport oxygen to tissues

Red blood cells are highly specialized cells that do not have a nucleus (lost during maturation). Most of the cells are represented by biconcave disks, the average diameter of which is 7 μm, and the peripheral thickness is 2-2.5 μm. There are also spherical and dome-shaped red blood cells.

Due to the shape, the surface of the cell is significantly increased for gas diffusion. Also, this shape helps to increase the plasticity of the red blood cell, due to which it is deformed and moves freely through the capillaries.

Human red blood cells and leukocytes

In pathological and old cells, plasticity is very low, and therefore they are retained and destroyed in the capillaries of the reticular tissue of the spleen.

The erythrocyte membrane and the anucleation of cells provide the main function of erythrocytes - the transport of oxygen and carbon dioxide. The membrane is absolutely impermeable to cations (except potassium) and highly permeable to anions. The membrane consists of 50% proteins that determine the blood group and provide a negative charge.

Red blood cells differ from each other in:

Video: Red blood cells

Red blood cells are the most numerous cells in human blood

Red blood cells are classified according to their degree of maturity into groups that have their own distinctive characteristics

In peripheral blood there are both mature, young and old cells. Young red blood cells that contain remnants of nuclei are called reticulocytes.

The number of young red blood cells in the blood should not exceed 1% of the total mass of red cells. An increase in the content of reticulocytes indicates increased erythropoiesis.

The process of formation of red blood cells is called erythropoiesis.

Bone marrow of the skull bones;
Pelvis;
Torso;
Sternum and vertebral discs;
Until the age of 30, erythropoiesis also occurs in the humerus and femur.

Every day, the bone marrow produces more than 200 million new cells.

After full maturation, the cells penetrate into the circulatory system through the capillary walls. The lifespan of red blood cells ranges from 60 to 120 days. Less than 20% of red blood cell hemolysis occurs intravascularly, the rest is destroyed in the liver and spleen.

Functions of red blood cells

Perform a transport function. In addition to oxygen and carbon dioxide, cells transport lipids, proteins and amino acids;
Helps remove toxins from the body, as well as poisons that are formed as a result of the metabolic and life processes of microorganisms;
Actively participate in maintaining the balance of acid and alkali;
Participate in the process of blood clotting.

Hemoglobin

The erythrocyte contains a complex iron-containing protein, hemoglobin, the main function of which is the transfer of oxygen between tissues and lungs, as well as partial transport of carbon dioxide.

Hemoglobin contains:

A large protein molecule is globin;
The non-protein structure built into globin is heme. The core of heme contains an iron ion.

In the lungs, iron binds with oxygen, and it is this connection that contributes to the acquisition of a characteristic color by the blood.

Blood groups and Rh factor

On the surface of red blood cells there are antigens, of which there are many varieties. This is why one person's blood can be different from another's. Antigens form the Rh factor and blood group.

The presence/absence of Rh antigen on the surface of an erythrocyte is determined by the Rh factor (if Rh is present, Rh is positive, if not, Rh is negative).

Determining the Rh factor and blood group of a person is of great importance when transfusing donor blood. Some antigens are incompatible with each other, causing destruction of blood cells, which can lead to the death of the patient. It is very important to receive a blood transfusion from a donor whose blood type and Rh factor match those of the recipient.

Leukocytes are blood cells that perform the function of phagocytosis

Leukocytes, or white blood cells, are blood cells that perform a protective function. White blood cells contain enzymes that destroy foreign proteins. Cells are able to detect harmful agents, “attack” them and destroy them (phagocytose). In addition to eliminating harmful microparticles, leukocytes take an active part in cleansing the blood of decay and metabolic products.

Thanks to antibodies produced by white blood cells, the human body becomes resistant to certain diseases.

Leukocytes have a beneficial effect on:

Metabolic processes;
Providing organs and tissues with the necessary hormones;
Enzymes and other necessary substances.

Leukocytes are divided into 2 groups: granular (granulocytes) and non-granular (agranulocytes).

Granular leukocytes include:

The group of non-granular leukocytes includes:

Neutrophils

The largest group of leukocytes, accounting for almost 70% of their total number. This type of leukocyte received its name due to the ability of the granularity of the cell to be stained with paints that have a neutral reaction.

Neutrophils are classified according to the shape of their nucleus into:

Young, without a core;
Rods, the core of which is represented by a rod;
Segmented, the core of which consists of 4-5 segments connected to each other.

Neutrophils

When counting neutrophils in a blood test, the presence of no more than 1% of young, no more than 5% of band cells and no more than 70% of segmented cells is acceptable.

The main function of neutrophil leukocytes is protective, which is realized through phagocytosis - the process of detecting, capturing and destroying bacteria or viruses.

1 neutrophil can “neutralize” up to 7 microbes.

Neutrophils also take part in the development of inflammation.

Basophils

The smallest subtype of leukocytes, the volume of which is less than 1% of the number of all cells. Basophilic leukocytes are named due to the ability of the granular cells to be stained only with alkaline dyes (basic).

The functions of basophilic leukocytes are determined by the presence of active biological substances in them. Basophils produce heparin, which prevents blood clotting at the site of the inflammatory reaction, and histamine, which dilates the capillaries, which leads to rapid resorption and healing. Basophils also contribute to the development of allergic reactions.

Eosinophils

A subtype of leukocytes, which got its name due to the fact that its granules are stained with acidic dyes, the main of which is eosin.

The number of eosinophils is 1-5% of the total number of leukocytes.

Cells have the ability of phagocytosis, but their main function is the neutralization and elimination of protein toxins and foreign proteins.

Eosinophils also participate in the self-regulation of body systems, produce neutralizing inflammatory mediators, and participate in blood purification.

Monocytes

A subtype of leukocytes that does not have granularity. Monocytes are large cells resembling a triangle shape. Monocytes have a large nucleus of various shapes.

Monocyte formation occurs in the bone marrow. During the process of maturation, a cell goes through several stages of maturation and division.

Immediately after a young monocyte matures, it enters the circulatory system, where it lives for 2-5 days. After this, some of the cells die, and some go to “ripen” to the stage of macrophages - the largest blood cells, whose lifespan is up to 3 months.

Monocytes perform the following functions:

Produce enzymes and molecules that contribute to the development of inflammation;
Participate in phagocytosis;
Promote tissue regeneration;
Helps in the restoration of nerve fibers;
Promotes the growth of bone tissue.

Monocytes

Macrophages phagocytose harmful agents found in tissues and suppress the proliferation of pathogenic microorganisms.

Lymphocytes

The central link of the defense system, which is responsible for the formation of a specific immune response and provides protection from everything foreign in the body.

The formation, maturation and division of cells occurs in the bone marrow, from where they are sent through the circulatory system to the thymus, lymph nodes and spleen for full maturation. Depending on where complete maturation occurs, T lymphocytes (matured in the thymus) and B lymphocytes (matured in the spleen or lymph nodes) are distinguished.

The main function of T lymphocytes is to protect the body by participating in immune reactions. T lymphocytes phagocytose pathogenic agents and destroy viruses. The reaction carried out by these cells is called “nonspecific resistance”.

B-lymphocytes are cells that are capable of producing antibodies - special protein compounds that prevent the proliferation of antigens and neutralize toxins released by them during their life processes. For each type of pathogenic microorganism, B lymphocytes produce individual antibodies that eliminate the specific type.

T-lymphocytes phagocytose mainly viruses, while B-lymphocytes destroy bacteria.

What antibodies do lymphocytes produce?

B lymphocytes produce antibodies, which are found in cell membranes and in the serum portion of the blood. As an infection develops, antibodies begin to rapidly enter the bloodstream, where they recognize pathogenic agents and “inform” the immune system about this.

The following types of antibodies are distinguished:

Immunoglobulin M - makes up up to 10% of the total amount of antibodies in the body. They are the largest antibodies and are formed immediately after the introduction of the antigen into the body;
Immunoglobulin G is the main group of antibodies that plays a leading role in protecting the human body and forms immunity in the fetus. The cells are the smallest among antibodies and are able to cross the placental barrier. Together with this immunoglobulin, immunity from many pathologies is transferred to the fetus from the mother to her unborn child;
Immunoglobulin A - protects the body from the influence of antigens entering the body from the external environment. The synthesis of immunoglobulin A is produced by B-lymphocytes, but they are found in large quantities not in the blood, but on the mucous membranes, breast milk, saliva, tears, urine, bile and secretions of the bronchi and stomach;
Immunoglobulin E - antibodies secreted during allergic reactions.

Lymphocytes and immunity

After a microbe meets a B-lymphocyte, the latter is able to form “memory cells” in the body, which determines resistance to pathologies caused by this bacterium. To create memory cells, medicine has developed vaccines aimed at building immunity to particularly dangerous diseases.

Where are leukocytes destroyed?

The process of destruction of leukocytes is not fully understood. To date, it has been proven that of all the mechanisms of cell destruction, the spleen and lungs take part in the destruction of white blood cells.

Platelets are cells that protect the body from fatal blood loss

Platelets are formed blood elements that participate in hemostasis. They are represented by small biconvex cells that do not have a nucleus. The diameter of the platelet varies between 2-10 microns.

Platelets are produced by red bone marrow, where they undergo 6 cycles of maturation, after which they enter the bloodstream and remain there for 5 to 12 days. Platelet destruction occurs in the liver, spleen and bone marrow.

While in the bloodstream, platelets have the shape of a disk, but when activated, the platelet takes on the shape of a sphere on which pseudopodia are formed - special outgrowths with the help of which platelets connect to each other and adhere to the damaged surface of the vessel.

In the human body, platelets perform 3 main functions:

They create “plugs” on the surface of a damaged blood vessel, helping to stop bleeding (primary thrombus);
Participate in blood clotting, which is also important for stopping bleeding;
Platelets provide nutrition to vascular cells.

Platelets are classified into.

What red blood cells look like under a microscope. Human blood cells. The structure of blood cells. Sensitive ear hairs

Conclusion

What is a healthy particle

Five interesting facts

The structure of a malignant particle

Core

Proteins

Mitochondria

Plasma membrane

Malignant particles of different organs

Lungs' cancer

Breast cancer

Skin cancer

Red blood cells

Leukocytes

Neutrophils

Basophils

Eosinophils

Monocytes

Platelets

Conclusion

Human blood cells. The structure of blood cells

Anatomy of the human cardiovascular system

Composition of blood and the significance of its cells

Plasma

Red blood cells

Function

Platelets

Meaning

Leukocytes

Role in the body

Stem cells

Why are stem cells needed?

Blood cell norms in medical analysis

Blood under a microscope and human blood groups

Red blood cells

Leukocytes

Neutrophils

Basophils

Eosinophils

Lymphocytes

Monocytes

Platelets

Conclusion

Blood under a microscope and human blood groups

Comments (3)

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Human blood cells - functions where they are formed and destroyed

Red blood cells are cells that transport oxygen to tissues

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Red blood cells are the most numerous cells in human blood

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Hemoglobin

Blood groups and Rh factor

Leukocytes are blood cells that perform the function of phagocytosis

Neutrophils

Basophils

Eosinophils

Monocytes

Lymphocytes

What antibodies do lymphocytes produce?

Lymphocytes and immunity

Where are leukocytes destroyed?

Platelets are cells that protect the body from fatal blood loss