Comparison of the Effects of Gibberellic Acid and Water on the Wild Type and Rosette Phenotypes
... These actions are examples of the different effects of hormones. Another hormone, and the one from which the acid in the following experiment is derived, is gibberellin. ... In this experiment, two types of the plant Brassica rapa were treated with gibberellic acid, and their growth pattern was compared to the same two types of the plant that were given no hormone. The two types of plants are also different in that the wild type contains natural gibberellins while the rosette does not (handout…Whitehead, 2003? ... The hypothesis is that plants treated with gibberellic acid will be taller than nontreated plants. ... The hypothesis is that wild type plants will grow taller than rosette phenotypes due to natural gibberellins. ... This was done so that water would be able to enter the bottom of the cup to provide moisture for the soil and seeds. ... Two of the four cups were labeled “rosette” and the other two were labeled “wild type”. One of each of the two groups was also labeled as “water” while the other was labeled “gibberellic acid”. The four cups read as follows: Rosette-water Rosette-GA Wild type-water Wild type-GA The wet tip of a pencil was used to pick up three plant seeds for each cup. The cups labeled “rosette” received seeds of the rosette phenotype of B. rapa, while those marked “wild type” received seeds of the wild type. ... After the seeds were planted, the cups were placed in long pans of water which provided a continuous water supply during the growth period. ... Next, one drop of the appropriate solution (water or GA) was applied to the top of each plant in the cup with the respective label.