Question 7
FSome plants have leaves with green parts and white parts.
A student does an experiment with one of these plants.
Step 1: she keeps the plant in the dark for 48 hours.
Step 2: she fixes a strip of black paper across one leaf.
Step 3: she puts the plant in bright light for 6 hours.
Step 4: she removes the leaf, puts it in boiling water and then in hot ethanol, and tests it for starch.
The Figure shows the leaf before and after the starch test.
Figure
a.[1]
Name the solution used to test for starch.
b.[2]
Explain why the plant was kept in the dark for 48 hours before the experiment.
c.[2]
Use the Figure to explain what the results show about the conditions needed for photosynthesis.
d.[1]
Give the reason why the leaf is put in hot ethanol before the starch test.
1.4 Photosynthesis Questions
117 exam-style questions on OCR GCSE Biology 1.4 Photosynthesis, covering 1.4.1 Photosynthesisers as biomass producers, 1.4.2 Factors affecting the rate of photosynthesis, and 1.4.3 Limiting factors in photosynthesis. Each one has a worked solution and a mark scheme showing where the marks go.