1. Materials IAA solution, 0.01% w/v = 100 parts per million (ppm) Radish seeds 8 Test tubes or Bottles Distilled Water 8 Petri Dishes 8 Acetate Grids and Cotton wool ACTIVITY To investigate the effect of IAA growth regulator on plant tissue

2. Method A. Preparing different concentrations of IAA 1. Label the 8 Petri dishes, droppers and bottles 1, 2, 3... 8 2. Using a syringe, add 10 ml IAA solution to Bottle 1. 3. Using another syringe, add 9 ml distilled water to each of the bottles numbered 2 to 8. 76543218

3. 4. Using Dropper 1, remove 1 ml IAA solution from Bottle 1 and add it to Bottle 2. Place the cap on Bottle 2 and mix. 5. Using Dropper 2, remove 1 ml IAA solution from Bottle 2 and add it to Bottle 3. Mix.

4. 6. Using a different dropper each time, repeat this procedure up to Bottle 7. 7. After mixing Bottle 7, remove 1 ml so that each bottle now contains 9 ml of solution. 8. Leave Bottle 8 as it is, with just 9 ml distilled water – it will act as the control.

5. Serial dilution—making different concentrations of IAA

6. Tube12345678 IAA 10 mls -- control Water--9 mls IAA conc 10 2 10 1 10 0 10 -1 10 -2 10 -3 10 -4 0 *ppm1001010.10.010.0010.00010 Serial dilution—making different concentrations of IAA *ppm = parts per million

9. 7. Draw a graph of the % stimulation and inhibition of root and shoot growth against IAA concentration. Put IAA concentration on the horizontal [X] axis