[问答题]
The graph shows the effect of
tqs/ tf t0wx2 st04ci3 differing concentrations
a/opat*/86 x )+s(f tslulpb uof the growth hormone Indole-3-acetic acid (IAA) on the sh
8utatu+b (a) plsolx//*fsp 6oot growth rate of the sesame seed plant (Sesamum indicum). IAA is an auxin.
1.1.Describe the trend shown in the graph.
1.2.Outline one reason that percentage change was used rather than change in length.
2.1.State two variables that would need to be controlled in this experiment.
2.2.Explain why it is important that one of the factors you chose in (i) needs to be controlled in this experiment.
3.1.Explain how auxins such as IAA promote shoot growth.
3.2.Deduce, with a reason, which concentration of IAA should be used to grow sesame seed plants.