An agronomist investigates how nitrogen fertiliser, and the density of quinoa seeds planted per square metre, affect the crop yield.
She applies different masses of nitrogen fertiliser to plots containing different planting densities of quinoa seeds, and measures the yield after harvest.
The table shows her results.
| Mass of nitrogen fertiliser added in kg\text{kg}kg per hectare | Number of seeds planted per m2\text{m}^2m2 | Yield of quinoa in tonnes per hectare |
|---|---|---|
| 0 | 20 | 5.1 |
| 0 | 40 | 4.3 |
| 50 | 20 | 7.4 |
| 50 | 40 | 6.1 |
| 100 | 20 | 6.2 |
| 100 | 40 | 4.9 |
Identify the mass of fertiliser and the seeding density that produced the highest yield of quinoa.
Describe the effect that changing the mass of nitrogen fertiliser has on the yield of quinoa.
Explain the effect that changing the number of seeds planted has on the yield of quinoa.
74 exam-style questions on Edexcel IGCSE Biology Food production. Each one has a worked solution and a mark scheme showing where the marks go.