Answer
Exocytosis is the process of discharging material from a cell. It basically looks like endocytosis in reverse.
The purpose of exocytosis is secretion. Hormones, some enzymes, milk from mammary glands all use exocytosis to secrete their material into the body.
Work Step by Step
Exocytosis comes from exo- "out", cyt- "cell" and -osis "process". Material moves from inside the cell to outside the cell.
The material that undergoes exocytosis first forms a secretory vesicle in the cell. The secretory vesicle moves to the plasma membrane and docks. The membrane is pulled inward, creating a dimple that fuses with the vesicle. This allows the vesicle to secrete its contents.
Exocytosis is used for secretion. Hormones, like insulin, are secreted using exocytosis.