A student investigated whether transpiration is faster in bright light. The student placed one potted plant on a sunny windowsill and an identical potted plant in a dark cupboard. Each pot was weighed at the start and again after 6 hours, and the loss in mass was calculated.
Explain why the loss in mass of the pot can be used as a measure of the rate of transpiration.
Give two variables the student should have controlled in this investigation.
The plant on the windowsill lost more mass than the plant in the cupboard. Explain why this result does not show that light intensity caused the difference.
Suggest one change to the method that would make sure only the water lost from the plant was measured.
38 exam-style questions on AQA GCSE Biology 2.3 Plant tissues, organs and systems, covering 2.3.1 Plant tissues and 2.3.2 Plant organ system. Each one has a worked solution and a mark scheme showing where the marks go.