Use your knowledge of indoleacetic acid (IAA) to explain the growth curvature shown in Figure 1.

Using the procedure in Figure 2 and the calibration curve in Figure 3, describe how you could compare the IAA concentration in shoot tips from two different plant species.

In your answer you should refer to all the variables that should be controlled to produce a valid comparison.

State two conclusions about IAA that you can make from the results shown in Table 1.

1

2