Endocytosis by a capillary endothelial cell, TEM

Endocytosis (pinocytosis) by a capillary endothelial cell (central nervous system), transmission electron micrograph (TEM). The movement of macromolecules such as proteins or polysaccharides into or out of the cell is called bulk transport. There are two types of bulk transport, endocytosis and exocytosis (both require the expenditure of energy - ATP). Endocytosisis is the process by which materials move into the cell. There are three types of endocytosis: phagocytosis, pinocytosis, and receptor-mediated endocytosis. In pinocytosis (or cellular drinking) the cell engulfs drops of fluid by pinching in and forming vesicles. Pinocytosis is a non-specific process in which the cell takes in whatever solutes that are dissolved in the liquid it envelops. Magnification: x12,880 when shortest axis printed at 25 millimetres.