Human blood cells and consists of the liquid portion, or serum.The liquid portion - a solution which contains a certain number of micro and macronutrients, fats, carbohydrates and proteins.Blood cells are divided into three main groups, each of which has its own particular structure and function.Let us consider each of them more closely.
Red blood cells or red blood cells
Red blood cells - a rather large cells that have very characteristic shape of biconcave disk.The red corpuscles contain no nucleus - in its place is the hemoglobin molecule.Hemoglobin - is a fairly complex compound which is composed of a protein portion, and the divalent iron atom.Erythrocytes are produced in the bone marrow.
Red blood cells have many functions:
- Gas exchange - this is one of the main functions of blood.Direct participation in this process takes is hemoglobin.In smaller vessels, pulmonary blood is oxygenated, which is connected with the iron in hemoglobin.This relationship is reversible, so with oxygen remains in the tissues and cells where it is needed.Simultaneously, the loss of one oxygen atom binds hemoglobin with carbon dioxide, which is transferred to the output light and to the environment.
- Furthermore, on the surface of red blood cells have a specific polysaccharide molecules or antigens that determine and Rh blood group.
White blood cells, or leukocytes
White blood cells - a rather large group of different cells, whose main function is to protect the body against infections, toxins and foreign bodies.These cells have a nucleus, can change its shape and pass through the tissue.Formed in the bone marrow.White blood cells can be divided into several types:
- Neutrophils - a large group of white blood cells that have the ability to phagocytosis.In their cytoplasm contains many granules filled with enzymes and biologically active substances.When penetrating into the body of bacteria or viruses, neutrophil moves to foreign cells, captures and destroys it.
- Eosinophils - blood cells that perform a protective function, destroying pathogens by phagocytosis.Work in the mucosa of the respiratory tract, bowel and urinary system.
- Basophils - a small group of small oval cells that take part in the development of inflammation and anaphylactic shock.
- macrophages - cells that are actively destroying the viral particles and bacterial cells but have clusters of granules in the cytoplasm.
- Monocytes - are characterized by a specific function, as they can develop or, or, conversely, inhibit the inflammatory process.
- lymphocytes - white blood cells responsible for the immune response.Their feature is the ability to generate immunity to the microorganism which has penetrated at least once in the human blood.
platelets or platelets
platelets - a small, nuclear-free human blood cells oval or round shape.After activation, on the outer membrane of the cell are formed protrusions, whereby it resembles a star.
Platelets have a number of quite important functions.Their goal - the formation of so-called blood clot.In place of the injured was the first to get the platelets, which are under the influence of enzymes and hormones begin to stick together, forming clots.This clot seals the wound and stops bleeding.Furthermore, these blood cells are responsible for the integrity and stability of the vessel walls.
can say that the blood - this is quite a complex and multi-purpose kind of human connective tissue, is designed to maintain a normal life.
