Question 6(d)(i)
[Maximum number: 1]
State why the student:
kept the lamp at the same distance during the investigation,
CAIE IGCSE Biology 22.2.2 Planning Experiments and Investigations
Practise choosing environmental variables that could affect seedling growth and explaining how fixed apparatus settings keep light intensity controlled.
How this is tested
- choose environmental control variables such as temperature, light, pH and oxygen supply
- explain that a fixed lamp distance controls light intensity, not temperature or fairness alone