Fabrics of man

Human tissues are the structures of cells and extracellular living beings that have developed historically. Each structure is endowed with certain morphofunctional characteristics inherent only to it. In the body, all human tissues interact. This provides a morphofunctional unity in it.

Types of human tissue

There are four types of cellular structures. In the body there is epithelial, nervous, muscle and connective tissue.

The borderline (epithelial) structure includes epithelial cells that lining the surface of the body, the mucosa of the cavities and internal organs in the body, and also form glands of both internal and external secretion.

The cells of human epithelial tissue lining the mucosa are located in the basal membrane. The inner surface of this layer faces directly to the external environment. Nutrition of epithelial tissue is carried out by diffusion of oxygen and substances through the basement membrane from blood vessels.

Depending on the shape of the cells, classify flat (skin), cylindrical (intestine), cubic (capsule of the renal glomerulus) layer. Depending on the number of layers, one-layer and multi-layer fabric are distinguished. If all cells in the structure reach the membrane, then this is a single-layered epithelium. In the case where cells are bound to the membrane in only one row, and in the other they are free, then this is a multilayered epithelium. Single-layer epithelial tissue can be single-core or multinucleate. This depends on the level at which the cores are located. In some cases in the structure there are ciliated cilia facing the external environment.

A very diverse structure has a connective tissue of man. However, all its varieties are formed from the mesenchyme (the middle germinal leaf). The connective structure should include fibrous, cartilaginous, lymphatic, hematopoietic tissue and blood. All these varieties are related to the structures of the internal environment.

The blood contains uniform elements: platelets, white blood cells, erythrocytes. In addition, there is a liquid plasma in it. In the plasma are hormones, immune bodies, nutritional components. In the bone marrow (red) is the hematopoietic tissue. In the lymph nodes, intestinal mucosa, liver, spleen, thymus and other organs, the lymphatic structure is located.

Connective tissues of the fibrous structure, other than cells, include other elements as well. They, in particular, contain an intermediate substance, represented in the form of collagen, elastic, argyophilic and reticular fibers, which are contained in the basic substance.

In all tissues and organs there are connective tissue fibers. However, they are most pronounced where there is a high mechanical load.

Bone cells are present in the bone structure. They have the ability to form an intermediate substance, which consists of mineral salts, as well as connective tissue fibers.

The cartilaginous structure is subdivided into hyaline, elastic and fibrous cartilage. In the fibrous cartilage contains chondrin with a sufficient amount of collagen fibers in order to impart strength to the cartilage. In the elastic cartilage layer, chondrin, in addition to collagen, contains elastic fibers and cartilaginous cells, due to which it possesses a certain degree of elasticity. The hyaline structure is quite dense, but less durable than the others.

Human muscle is referred to as the heart muscle, the fibers are smooth and striped. Due to this structure, the blood vessels, internal organs, and the movement of parts of the body are reduced. Reduction of striated muscles occurs according to the will of the person. Heart muscle and smooth fibers are part of the structure of internal organs. They do not obey the desires of man.