Ocean water freezes just like freshwater, but at lower temperatures. Fresh water freezes at 32 degrees Fahrenheit but seawater freezes at about 28.4 degrees Fahrenheit, because of the salt in it. When seawater freezes, however, the ice contains very little salt because only the water part freezes. It can be melted down to use as drinking water.
Most cell types are very permeable to water. an exception is cells of the distal nephron, which can be either impermeable or permeable, depending upon the absence or presence of aquaporins.
