What will happen to freshwater algae when placed in the ocean?

Question

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Answer 1

It would dehydrate and die.

Answer 2

Probably croak; fresh water organisms do not have the chemical resistance to salt water necessary to survie out there, meaning the oceans are a death trap to any fresh water organism, except for Salmon which go to fresh water to spawn, thing is, as they mature, their biology changes to live out in the oceans.

Answer 3

Freshwater algae have evolved to keep their osmotic balance in check in fresh water. If placed in a saltwater environment the water in their bodies will escape down the osmotic gradient into the ocean. Because they lack the mechanisms to pump water back into their bodies they will dehydrate and die.