vesicle

vesicle? small bubble in a cell, organelle:
http://en.wikipedia.org/wiki/Vesicle_(biology_and_chemistry)
enclosed by libid bilayers.
during endocytosis, protein absorption it form naturally.

liposomes, artificial.
uniamellar vesciles and multilamellar.
plasma membrane enclosed it.
fuse its plasma membrane to release their contents outside of cell.
also fuse with other organelles within the cell.

functions of vesciles.
different form from cytosolic environment.
for organizing cellular substances its basic tool.
used in metabolism, transport, buoyancy control, enzyme storage, chemical reaction chamber.