Answer:water moves out of the cell and it undergoes plasmolysis
Explanation:algae cells are plant cell.they have chlorophyll, carotenoids and phycobillins as their photosynthetic pigments.
They also possesses cellulose cell walls .
During osmosis,water moves from a region of low concentration of solute to a region of high concentration of solute.
In the above case,both the algae cell and it's surrounding solution has the same concentration of solute . however as solute is added to the solution it becomes more concentrated and water moves out of the algae cell .As the cell continues to lose water,the cell body pulls away from the cell wall causing a phenomenon called plasmolysis.