For a cell to survive, ion concentrations inside and outside the cell need to be the same. If extra ions are not pumped out of the cell, water can enter the cell, causing it to swell and burst.
The most important function of osmosis is stabilising the internal environment of an organism by keeping the water and intercellular fluids levels balanced. In all living organisms, nutrients and minerals make their way to the cells because of osmosis. This obviously is essential to the survival of a cell.
Since they cannot see very well or even at all in some cases, these animals use echolocation instead to orient themselves, to find where they are, and to find food.
