A solution causes guard cells to close the stomata where the solution is applied. The solution does not affect any other leaf cells.
The solution was applied to the upper surface of leaf R and to the lower surface of leaf S. The leaves were otherwise identical and were kept under the same conditions in bright light.
Which prediction is supported by this information?
Both leaves will show the same decrease in photosynthesis because their surfaces have equal areas
Leaf S will show a greater decrease in photosynthesis because less carbon dioxide can enter
Leaf R will show a greater decrease in photosynthesis because the palisade cells are near the upper surface
Neither leaf will show a decrease in photosynthesis because photosynthesis occurs in the mesophyll
74 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.