You can recognize the process of pinocytosis when THE CELL IS ENGULFING EXTRACELLULAR FLUID.
Pinocytosis is one of the forms of endocytosis; it involves the movement of large particle into the cell by an in-folding of the plasma membrane. It is an active form of transport used to move materials into the cells.
There are sometimes similarities in the embryonic stages of organisms that do not exist in the adult stages.
Decent from a common ancestor; natural selection.
