Explain why the student removed the shoot tip from each seedling.

Explain why the student added glucose solution to each Petri dish.

Explain why the lids were kept on the Petri dishes.

Describe and explain the results shown in Table 1 and suggest how the results might have differed if lengths of root had been used.

The student produced the different concentrations of IAA using a stock 1 g dm–3 solution of IAA (1 g dm–3 = 1 part per thousand) and distilled water.

Complete Table 2 with the volumes of stock IAA solution and distilled water required to produce 40 cm3 of 10 ppm (parts per million) IAA solution.