Blood vessels between arterioles and venules that pass through capillary beds but are not true capillaries. Like arterioles, these vessels ahve smooth muscles present in the tunica media that allows it to act as a shut to regulate blood flow in the true capillaries that branch from it.
These vessels from the bulk fo the capillary bed. They brand away from a petarteriole at its arteriole end and return to merge with the metarteriole at its venule end.
Making up the majority of the capillaries, these vessels have continuous, unbroken walls consisting of cells that are connected by tight junctions.
These permeable vessles have continuous walls between endothelial cells, but the cells have numerous pores and are found in the kidneys, lining the small intestine, and in other areas.
Found in bone marrow, the spleen, and the liver, these capillaries have large gaps between endothelial cells that permit the passage of blood cells.