A student investigated the effect of gravity on the growth of seedling roots. They set up two experiments in a dark room:
What biological term is given to a growth response of a plant towards or away from a directional stimulus?
What is the role of Experiment 2 in this investigation?
Predict the appearance of the roots in Experiment 1 and Experiment 2 after 48 hours48\text{ hours}48 hours.
Give one control variable (other than light) that must be kept constant between both experiments.
59 exam-style questions on AQA GCSE Biology 5.4 Plant hormones, covering 5.4.1 Control and coordination and 5.4.2 Use of plant hormones (HT only). Each one has a worked solution and a mark scheme showing where the marks go.