When people don't know how to drive the boat correctly and they loose control.
If a cell membrane became impermeable, instead of selectively permeable, the cell would not remain alive, though certain organisms would be able to stay alive longer than others. This is because the cell membrane allows essential molecules and substances such as oxygen into the cell, while allowing harmful substances, like waste, out of the cell.
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Fish or any organism in the water...
One will be due to climatic change or it might be coz of evolution