Transport mechanisms — practice question

A student performed an investigation to estimate the water potential of potato tissue. The main stages of the method and of the processing of the results are shown in Fig. 6.1. Six sucrose solutions of different concentrations were prepared, and the same volume of each was transferred into a labelled beaker. The concentrations ranged from $0.0$ to $0.5\ \text{mol dm}^{-3}$. Six potato blocks of equal size were cut from the same potato, blotted dry and weighed. One potato block was placed in the solution in each beaker for 30 minutes. After this period, the block was removed, blotted dry and weighed again. The experiment was repeated twice. The mean percentage change in mass of the potato tissue was calculated for each sucrose concentration used, and a graph of mean percentage change in mass of potato tissue against sucrose concentration was drawn.