A young plant grows below a dense layer of leaves. Light reaches its shoot mainly through an opening on the right-hand side, and the shoot curves towards the opening.
A root of the same plant initially grows horizontally and then curves downwards.
State the name of the growth response shown by the shoot.
State which side of the shoot has the higher auxin concentration.
State which side of the horizontal root has the higher auxin concentration.
Explain how auxin causes the root to curve downwards.
105 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.