Gibberellic Acid Experiment
Introduction: …show more content…
Hormones also determine many factors such as the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit. They affect which tissues grow upward and which grow downward, leaf formation and stem growth, plant longevity, and even plant death. (Boundless, 2016). The five main hormones important for plant growth are auxin, gibberellin, cytokinin, ethylene, and abscisic acid, each of which regulate different elements of plant growth. Gibberellin, or Gibberellic Acid (GA3) affects the length between nodes on a stem. A node is a place where a leaf attaches to a stem, therefore GA3 elongate these internodes. (Nelson, R. 2013). Originally discovered in Japan, after the Gibberella fujikuroi fungus infected rice plants, causing them to grow thin, fragile and tall, thus falling over. GA3 is now used by botanists and farmers to modify and regulate the growth of plants with hormone treatments. (Koratkar, S. 2016).
The chemical formula for gibberellic acid is C₁₉H₂₂O₆, however the are multiple different strands of gibberellic acid such as GA3, GA4 or GA7. In the experiment GA3 was used as it is not only the most studied gibberellin, but also has its primary effect on the growth of the stem and leaves, opposed to GA4 and GA7, which have their main effect on flowering and fruit development. When …show more content…
Then observations such as the number of leaves, drooping, upright, holes and tears are made. All plants were generally healthy. After all observations were made 8 drops of GA were added to the apical meristem of the two plants in the pots labelled 'GA3 '. These measurements and observations were then recorded every time the lab was entered, as well as the addition of 8 drops of GA. The plants were also watered when the lab was entered, usually with 30ml however 50ml were added over weekends.
On the final day the last set of measurements was collected, after which each plant was carefully cut off at soil level and weighed. Thin slivers of the node above the first set of leaves were also cut to place under a microscope and observe the structure of the bean stems.
Safety precautions: when performing an experiment such as this, which includes biological hazards such a hormones, as well as the risk of other harmful factors such as scalpels it is important to assess the risks and take steps necessary to avoid any incidents. A full risk assessment can be found in appendix