A student grows a tray of young spinach plants from the same batch of seed. She finds the mean dry mass per plant of a sample of the plants at the start of a growing period, and of a second sample of the plants 14 days later.
| Time | Mean dry mass per plant (g) |
|---|---|
| Start | 0.42 |
| After 14 days | 0.96 |
Give the increase in mean dry mass per plant during the 14 days.
Give one reason why the student measured dry mass rather than fresh mass.
Explain what the increase in dry mass shows about photosynthesis and respiration in the plants.
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.