Pinocytosis is the process by which a cell takes in extracellular fluid
by the invagination of the cell membrane.
Rather than entering and passing through the cell membrane as individual
molecules, a droplet becomes bound to the membrane. A pocket then forms
and pinches off to form a vesicle, which
subsequently ruptures, releasing its contents into the cytosol.
Pinocytosis ("cell drinking") is a form of endocytosis.
|An amoeba showing pinocytosis