A student placed some germinating bean seeds on their side in a dark cupboard. The roots were horizontal.
Half of the seeds were left stationary. The other half were fixed to a turntable that rotated slowly, so that each side of the root faced downwards in turn.
Describe what would happen to the roots of the stationary seeds.
The roots on the rotating turntable grew straight out horizontally.
Explain why.
Explain why both groups of seeds were kept in the dark.
Give two variables that the student should control.
46 exam-style questions on Edexcel GCSE Biology 6.3 Plant hormones, covering 6.3.1 Plant hormones and tropisms and 6.3.2 Commercial uses of plant hormones. Each one has a worked solution and a mark scheme showing where the marks go.