Capillaries

capillariesCapillaries, the smallest (hairline) vessels, which moves blood (blood capillaries) or lymph (lymphatic capillaries). The tissues and organs of human body receives the nutrients and oxygen through a very thin capillary walls, consisting of a single layer of flat cells (endothelium). In the cell lining of the capillaries do not have holes, and the transfer of substances from the blood into the tissues and organs is performed by diffusion, with the exception of the capillaries of a liver and other bodies with submicroscopic pores. Capillary bore ranges from 0.003 to 0,016 mm Forming melkopatte network, the capillaries penetrating all tissues. Supply blood to the capillaries of the finest of the arteries, arterioles. Branched capillary unite, forming initial a narrow veins.
The study of the capillary network (see Capillaroscopy) is one of the methods of diagnostics of vascular disease. Cm. also Arteries, veins.