During vesicles in the cell fuse with the cell membrane, releasing their contents to the outside.
a: is crossed out
b: endocytosis
c: exocytosis
d: pinocytosis

Exocytosis is a process in which vesicles in the cell moves to the cell membrane to fuse with it. This way, the vesicles release their contents to the extracellular matrix. The purpose of exocytosis is to transport large molecules out of the cell because they are too large to pass passively through the cell membrane.

Exocytosis is the opposite process of endocytosis, in which cell engulfs molecules, such as proteins. Pinocytosis is fluid endocytosis.  In exocytosis, cell transports molecules, such as proteins, out of the cell.