A student used water culture (hydroponics) apparatus to investigate the effect of mineral deficiencies on plant growth.
A young plant was grown in a control solution containing all the mineral ions needed for healthy growth. A second young plant of the same species was grown in a solution containing all of these essential mineral ions except magnesium.
Suggest why air is bubbled through both nutrient solutions.
Suggest why the flasks containing the root solutions are covered in black paper to block out light.
Magnesium is an essential mineral ion for plants. State the name of the green pigment that contains magnesium and describe the physical appearance of the leaves of the plant grown without magnesium.
Suggest two abiotic factors, not related to the nutrient solution itself, that the student must keep identical for both plants during their growth.
Explain how the runoff of chemical fertilisers containing highly soluble mineral ions into a freshwater lake can cause the death of fish.
44 exam-style questions on Edexcel IGCSE Biology Human influences on the environment. Each one has a worked solution and a mark scheme showing where the marks go.