Some aquatic organisms that live in cold environments similar to that of the crabs have multiple forms of certain enzymes that catalyze reactions at various temperatures. Explain how having multiple forms of the enzymes would contribute to the fitness of these organisms. Both adult and juvenile red king crabs can be found in ocean water of a different salinity and osmolarity than their body tissues are. Explain why it is important to the crabs that they can regulate the osmolarity of their tissues.