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.