A student places pieces of soft stem tissue from the same plant into different sucrose solutions for 60 minutes.
The table shows the mean percentage change in mass of the pieces.
| Sucrose concentration (mol dm−3\text{mol dm}^{-3}mol dm−3) | Mean percentage change in mass (%) |
|---|---|
| 0.20 | +10.7 |
| 0.40 | +4.8 |
| 0.60 | -3.2 |
| 0.80 | -9.1 |
Assume that the percentage change in mass varies linearly between consecutive concentrations.
Calculate an estimate of the sucrose concentration at which there would be no percentage change in mass.
Explain why a piece of stem tissue kept in the 0.20 mol dm-3 solution would provide more support than a piece kept in the 0.80 mol dm-3 solution.
194 exam-style questions on OCR GCSE Biology 2.1 Supplying the cell, covering 2.1.1 Transport across cell membranes, 2.1.2 Mitosis and the cell cycle, 2.1.3 Importance of cell differentiation, and 2.1.4 Stem cells. Each one has a worked solution and a mark scheme showing where the marks go.