Pondweed is placed at a new distance from a lamp. In four consecutive minutes, it releases 9, 15, 20 and 20 bubbles.
Which change to the method would give the best estimate of the rate at the new distance?
Use only the first reading before starting repeated measurements.
Wait for a steady rate before starting repeated measurements.
Move the lamp continuously while collecting all four measurements.
Use a longer shoot before averaging all four measurements.
87 exam-style questions on Edexcel GCSE Biology 6.1 Photosynthesis, covering 6.1.1 Photosynthetic organisms as producers, 6.1.2a Limiting factors on the rate of photosynthesis, 6.1.2b Interactions of limiting factors on photosynthesis, and 6.1.3 Inverse square law and light intensity. Each one has a worked solution and a mark scheme showing where the marks go.