CAIE A Level Biology 9700 · Cell membranes and transport
A student placed potato tissue (plant cells) and red blood cells (animal cells) into separate beakers containing a 0.5 mol dm⁻³ sucrose solution. The water potential of this solution is lower than that of the cell contents. After 30 minutes, she observed the cells under a microscope.
Compare the likely responses of the plant cells and animal cells to this solution, explaining the reasons for any differences.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Compare means: Give similarities or differences between two things, and say which side each point belongs to. Write each point as a pair, for example: A is X, whereas B is Y. Two separate descriptions rarely earn the marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.