1) Cysts 2) Sacs 1) Rock cavities 
Vesicles: In dermatology, vesicles are small blisters, most often on the skin. Vesicles also can crop up on the mucous membranes, such as the buccal mucosa (the lining of the mouth). In anatomy, a vesicle is any small pouch. The word vesicle comes from the Latin diminutive vesiculum meaning a small bag or bladder.
Small membrane-bound spaces in most plant and animal cells that transport macromolecules into and out of the cell and carry materials between organelles in the cell.