Answer:
hypertonic to water and hypotonic to salt solution.
Explanation:
When two solutions of unequal solute concentrations are separated by a permeable membrane, water molecules move from the solution with lower solute concentration to the solution with higher solute concentration until an equilibrium is reached. The solution with higher solute concentration is referred to as being hypertonic while the other one is referred to as being hypotonic.
The cells of celery stalks have higher solute concentration in their cell saps compared to the surrounding fresh water. Hence, water keeps entering the cells, resulting in turgidity. The cells are therefore hypertonic to fresh water.
The salt solution however seemed to have more solute concentration compared to that of the cell sap of the celery stalks. This made the cells of the celery stalks to lose water to the surrounding solution, resulting in flaccidity. Hence, the cells are hypotonic to salt solution.
