A plant tissue laboratory grows two maize seedlings vertically under light that falls evenly from above. A slow-release gel patch supplies auxin to one side of the growing region of one root and one shoot. A coloured marker is placed beside one side of each organ. After 24 hours, both the root and the shoot have curved towards their marker.
Which pair of patch positions is consistent with these observations?
root patch beside its marker; shoot patch beside its marker
root patch opposite its marker; shoot patch opposite its marker
root patch beside its marker; shoot patch opposite its marker
root patch opposite its marker; shoot patch beside its marker
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.