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.
Sometimes a coma is induced in patients who are at high risk of brain injury from incidents such as physical trauma, drug overdose or life-threatening seizures. By reducing the activity in the brain and slowing its metabolism, an induced coma can help protect the neural tissue.he conclusions may not extend to cases of comatose patients who have suffered major brain damage, he said. The newly discovered coma state is characterized by electrical waves called Nu-complexes that are unlike other waveforms generated by the brain during known coma states, sleep or wakefulness.