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.
There are major differences between a coma and a deep sleep. A coma is a long state of unconsciousness during which a person appears to be sleeping and does not respond to their environment. The medical community uses very specific parameters when defining a person in a coma. A person with a coma: