Isotonic solutions will have the same or a very similar concentration when compared to the cell or microbe within it. Based on the chart above, Salmonella has a salt concentration as a percentage of volume of 0.9. If the salt concentration of a solution is 1% then 0.9 is the closest compared to the others. Paramecium will be hypotonic while Amoeba and Plankton would be hypertonic in this solution.