A farmer applied different concentrations off cytokinins to his pineapple plants and observed tne development of new shoots Over a period of time.
The result of his observation is shown below.
| S/No. | Conc. of Cytokinin(mg/litre) | No. of new shoots |
| 1 | 0 | 2 |
| 2 | 1 | 5 |
| 3 | 2 | 8 |
| 4 | 3.5 | 12 |
| 5 | 4 | 18 |
| 6 | 4.5 | 25 |
| 7 | 5 | 20 |
| 8 | 6 | 10 |
| 9 | 7.5 | 8 |
| 10 | 8 | 6 |
| 11 | 9 | 5 |
| 12 | 10 | 5 |
(a) Plot a graph to show the relationship between cytokinin concentration and shoot development.
(b) Use the graph to describe the effect of cytokinin concentration on shoot development.
(c) What advice should be given to the farmer based on the results from the graph?
(d) List (2) two substances in plants, (ii) two substances in animals which have similar effect as cytokinins.
Explanation
b) Description of graph: Initially the rate of production of new pineapple shoots increases; with Increased concentration of cytokinin
-Shoot development reaches its peak at optimum concentration of cytokinin/4.5mg/l
- Above this concentration, shoot development declines/decrease.