30. The significance of water's boiling and freezing points
to organisms is:
When water freezes, the resulting ice
molecules rearrange to make the ice less dense than water so it floats. This
ice then insulates the water and organisms below from low winter temperatures.
The boiling temperature of water is high
enough (100ūC) that water rarely boils on earth. Few organisms can survive in
boiling water.
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Slichter