A farmer grows tomatoes in a glasshouse. The farmer pays to add carbon dioxide to the air in the glasshouse. The table shows the yield of tomatoes at different carbon dioxide concentrations. Table
| Carbon dioxide concentration in % | 0.04 | 0.08 | 0.12 | 0.16 |
|---|---|---|---|---|
| Yield of tomatoes in kg\text{kg}kg per m2\text{m}^2m2 | 30 | 42 | 47 | 47 |
| The farmer is deciding whether to increase the carbon dioxide concentration from 0.12% to 0.16%. | ||||
| Which is the best advice for the farmer? |
Increase it, because more carbon dioxide always means more glucose is made.
Increase it, because the yield will rise by the same amount as before.
Do not increase it, because carbon dioxide at this level kills tomato plants.
Do not increase it, because another factor is limiting, so the extra cost gives no gain.
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.