During exocytosis, vesicles in the cell fuse with the cell membrane, releasing their contents to the outside.
It involves the movement of an intra cellular vesicle to the plasma membrane, then fusion.
There are many cellular processes that involve exocytosis. These include:
1.release of neurotransmitters from presynaptic neurons
2. secretion of enzymes, peptides hormones and antibodies from cells.
3. Placement of integral membrane proteins
4. Antigen presentation during an immune response.
5. acrosome reaction during fertilization.
6. Recycling of plasma membrane bound receptors