Waec Model Questions Vol1 2022 Biology Question 3

A group of students carried out an experiment to investigate the effect of sucrose concentration on the rate of osmosis in potato tuber discs. Uniform discs (diameter 1 cm, thickness ≈ 0.5 cm) were cut from a fresh potato and each disc was weighed to the nearest 0.01 g (initial mass). The discs were then placed in 50 mL of sucrose solutions of different concentrations (0%, 5%, 10% and 15% w/v) for 30 minutes at room temperature (≈25 °C). After the exposure, each disc was removed, surface water gently blotted with filter paper and weighed again (final mass). The data obtained are shown in the table below. | Concentration (%) | Initial mass (g) | Final mass (g) | |-------------------|------------------|----------------| | 0 | 2.45 | 2.78 | | 5 | 2.46 | 2.71 | | 10 | 2.44 | 2.62 | | 15 | 2.47 | 2.55 | Using the data above, answer the following questions: