Endocytosis is the entrance of material in the cell engulfed by portions of the cell membrane. Endocytosis can be classified as pinocytosis or phagocytosis. In pinocytosis small particles on the external surface of the membrane stimulate the invagination of the membrane inwards and vesicles full of that particles then detach from the membrane and enter the cytoplasm. In phagocytosis bigger particles on the external surface of the membrane induce the projection of pseudopods outwards enclosing the particles; the vesicle then detaches from the membrane and enters the cytoplasm receiving the name phagosome.
