The contractile vacuole acts to regulate quantity of water in a cell. In freshwater environments the concentration of solutes inside the cell is higher than outside the cell (i.e., the environment is hypotonic).he contraction of the contractile vacuole and the expulsion of water out of the cell is called systole. Water always flows first from outside the cell into the cytoplasm, and is only then moved from the cytoplasm into the contractile vacuole for expulsion.
Induced coma. A barbiturate-induced coma, or barb coma, is a temporary coma (a deep state of unconsciousness) brought on by a controlled dose of a barbiturate drug, usually pentobarbital or thiopental.
A long-term coma is often referred to as a persistent vegetative state. This can last for years, depending on the medical circumstances and the cause. In general, a coma is temporary, rarely lasting more than two to four weeks. After emerging from a coma, the prognosis is varied. Many people can recover fully, some require lifelong physical and occupational therapy, while others may recover only basic functions.